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i 

Technical Report Documentation Page

1. Report No.

FHWA-HOP-14-015

2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

Effectiveness of Safety and Public Service Announcement (PSA) 

Messages on Dynamic Message Signs (DMS)

5. Report Date

July 2014 

6. Performing Organization Code

7. Author(s)

Linda Boyle, Gustave Cordahi, Katie Grabenstein, Marwan Madi, 

Erika Miller, Paul Silberman

8. Performing Organization Report No.

9. Performing Organization Name and Address

Booz Allen Hamilton

8283 Greensboro Drive

McLean, VA 22102

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

DTFH61-11-D-00019

12. Sponsoring Agency Name and Address

Federal Highway Administration

HOTM-1, US Department of Transportation 

1200 New Jersey Ave SE

Washington, DC 20590

13. Type of Report and Period Covered

Final Report

14. Sponsoring Agency Code

HOTM-1 FHWA

15. Supplementary Notes

Jimmy Chu, Task Manager, FHWA Office of Operations, HOTM-1

16. Abstract

The report assesses the usefulness and effectiveness of safety and public service announcement (PSA) 

messages through surveys conducted in four urban areas in the United States: Chicago, IL; Houston, 

TX; Orlando, FL; and Philadelphia, PA. The surveys were designed to specifically address the types of 

safety and PSA messages for each respective city. A total of 2,088 survey responses were received and 

analyzed. The report further captures findings and recommendations based on the analysis of the 

survey responses.

17. Key Words

Dynamic Message Signs, Effectiveness, 

Public Service Announcements, Safety, 

Usefulness, Transportation Management 

Centers

18. Distribution Statement

No Restriction

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this page)

Unclassified

21. No. of Pages

92

22. Price

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized

Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs 

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TABLE OF CONTENTS

EXECUTIVE SUMMARY .......................................................................................................1

CHAPTER 1. INTRODUCTION .............................................................................................3

CHAPTER 2. ORGANIZATIONAL AND INSTITUTIONAL FRAMEWORKS FOR 

SAFETY AND PSA MESSAGES IN THE FOUR URBAN AREAS......................................5

Chicago .......................................................................................................................................5

Houston ......................................................................................................................................5

Orlando .......................................................................................................................................6

Philadelphia ................................................................................................................................7

CHAPTER 3. SURVEY DESIGN AND EXECUTION PLAN ...............................................9

Survey Design .............................................................................................................................9

Priority Messages ............................................................................................................9

Survey Format ...............................................................................................................12

Survey Questionnaire/Content .......................................................................................13

Survey Execution ......................................................................................................................13

Subject Recruitment .......................................................................................................13

Survey Locations for In-Person Interviews.....................................................................13

Pilot Study ................................................................................................................................14

Live In-Person Survey....................................................................................................14

Survey Results ...............................................................................................................15

Lessons Learned from the Pilot Survey .....................................................................................20

CHAPTER 4. ADJUSTMENTS TO THE SURVEY EXECUTION PLAN .........................21

Final Data Collection Logistics ................................................................................................. 21

Houston .....................................................................................................................21

Philadelphia ..................................................................................................................24

Orlando .....................................................................................................................28

Chicago .....................................................................................................................31

CHAPTER 5. RESULTS AND ANALYSIS ...........................................................................35

Descriptive Statistics .................................................................................................................35

Interpretations of PSAs ..................................................................................................37

Inferential Statistics ...................................................................................................................51

CHAPTER 6. FINDINGS AND RECOMMENDATIONS/GUIDANCE..............................56

APPENDIX A: SURVEY QUESTIONNAIRES ....................................................................60
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Chicago .....................................................................................................................................60

Houston ....................................................................................................................................64

Orlando .....................................................................................................................................68

Philadelphia ..............................................................................................................................72

APPENDIX B: SAMPLE SIZE CALCULATION ................................................................76

APPENDIX C: POTENTIAL SURVEY LOCATIONS BY CITY .......................................78

ACKNOWLEDGEMENTS ....................................................................................................82

List of Figures 

Figure 1. Photo. Pilot survey location. .......................................................................................15

Figure 2. Chart. Recognition of PSA messages. .........................................................................17

Figure 3. Chart. Number of collisions and number of ticket instances in the past 5 years. ..........20

Figure 4. Photo. Houston survey sites. .......................................................................................24

Figure 5. Photo. Philadelphia survey sites..................................................................................27

Figure 6. Photo. Orlando survey sites. .......................................................................................30

Figure 7. Photo. Chicago survey sites. .......................................................................................33

Figure 8 (a) (b) (c). Chart. PSA “ride safely, sober, live free, ride alive.” ..................................38

Figure 9 (a) (b) (c). Chart. PSA “eyes on road, hands on wheel.”...............................................39

Figure 10 (a) (b) (c) (d). Chart. Comparable PSA messages by city. ..........................................41

Figure 11 (a) (b). Chart. Additional PSA messages in Houston. .................................................42

Figure 12 (a) (b) (c) (d). Chart. Top 10 most recognized PSAs by city. ......................................44

Figure 13 (a) (b) (c) (d). Chart. “How much do you agree or disagree with the following 

statements...” ................................................................................................................47

Figure 14 (a) (b) (c) (d). Chart. “How important is it to provide information to drivers on the 

following...” .................................................................................................................49

Figure 15 (a) (b) (c) (d). Chart. “Would you change your driving behavior or habits when you 

see the following PSA on DMS while driving...” ..........................................................51

List of Tables 

Table 1. Recommended messages for Chicago, IL. ....................................................................10

Table 2. Recommended messages for Houston, TX. ..................................................................11

Table 3. Recommended messages for Orlando, FL. ...................................................................11

Table 4. Recommended messages for Philadelphia, PA. ............................................................12
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Table 5. Educational level of study participants. ........................................................................16

Table 6. Household income in $/year of study participants. .......................................................16

Table 7. Level of enforcement. ..................................................................................................18

Table 8. Would you change your driving behavior when you see the listed PSAs? ....................18

Table 9. Whether to change driving patterns or habits based on the following PSAs. .................19

Table 10. Original Houston survey locations. ............................................................................22

Table 11. Updated Houston survey locations based on state DOT feedback. ..............................22

Table 12. Survey locations visited in Houston during first visit. ................................................23

Table 13. Survey locations visited in Houston during second visit. ............................................23

Table 14. Original Philadelphia survey locations. ......................................................................25

Table 15. Updated Philadelphia survey locations based on state DOT feedback.........................25

Table 16. Survey locations visited in Philadelphia. ....................................................................26

Table 17. Original Orlando survey locations. .............................................................................28

Table 18. Updated Orlando survey locations based on state DOT feedback. ..............................28

Table 19. Survey locations visited in Orlando. ...........................................................................29

Table 20. Original Chicago survey locations..............................................................................31

Table 21. Updated Chicago survey locations based on state DOT feedback. ..............................31

Table 22. Survey locations visited in Chicago............................................................................32

Table 23. Demographics by survey city. ....................................................................................35

Table 24. Driving experience by survey city. .............................................................................36

Table 25. Socioeconomic characteristics of the survey respondents. ..........................................37

Table 26. General opinions of PSAs on DMS. ...........................................................................45

Table 27. Binary logit model for predicting perceived usefulness. .............................................52

Table 28. Binary logit model for predicting perceived effectiveness when compared to other 

media.............................................................................................................................55

Table 29. Perceived usefulness of PSAs on DMS summary. ......................................................57

Table 30. Perceived effectiveness of PSAs on DMS summary. ..................................................57

Table 31. PSAs on DMS – recommendations and guidance. ......................................................59

Table 32. Needed number of responses n as a function of P and d. ............................................77

Table 33. Potential survey locations -- Houston, TX. .................................................................78

Table 34. Potential survey locations -- Chicago, IL. ..................................................................79

Table 35. Potential survey locations -- Orlando, FL. ..................................................................80

Table 36. Potential survey locations -- Philadelphia, PA. ...........................................................81
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EXECUTIVE SUMMARY 

The number of transportation agencies that use dynamic message signs (DMS) to provide traffic 

information to motorists has increased dramatically over the past four decades. This growing 

trend of DMS deployment is a reflection of the public interest in more information about travel 

conditions and the importance of traveler information for transportation system operations. 

There has been extensive research conducted on traffic-related messages. However, policies 

regarding the display and type of non-traffic-related messages vary greatly among states. Thus, it 

is unclear how effective these non-traffic-related messages are in modifying driver or travel 

behavior. It is also unclear whether these messages are acceptable to motorists and whether they 

have a positive or negative impact on their driving behavior. 

The purpose of this study was to identify how safety and public service announcement (PSA) 

messages influence driver behavior and to ultimately assist the U.S. Department of 

Transportation (USDOT), transportation management centers (TMCs), state agencies, and local 

transportation partners in optimizing the utility of safety and PSA messages on DMS. Four urban 

areas in the United States were selected as study sites—Chicago, IL; Houston, TX; Orlando, FL; 

and Philadelphia, PA. Surveys were designed to specifically address the types of safety and PSA

messages for each respective city. The goal was to collect approximately 500 survey responses 

per city. In total, 2,088 responses were received. 

The data from each survey was summarized by city and analyzed in terms of usefulness and 

effectiveness. That is, summary statistics were compiled for the survey questions, and inferential 

statistics were used to examine the usefulness and effectiveness of safety and PSA messages. 

Usefulness was defined as the practical and functional application of PSAs on DMS, and 

examined within each city. For this study, effectiveness was defined as the ability of DMS to 

positively impact driver behavior by displaying safety and PSA messages. Usefulness and 

effectiveness are clearly subjective measures since they are based on individual perceptions. For 

the inferential model, only those variables that were shown to have a significant impact on the 

respective outcome (usefulness or effectiveness) for DMS remained in the final model. If a 

variable was not included, there was no significant impact on the usefulness or effectiveness of 

having safety and PSA messages on DMS. 

Most respondents reported that they do see safety and PSA messages on DMS while driving, at 

least sometimes. The majority also noted that safety and PSA messages on DMS are useful, with 

some even noting that those messages are more effective on DMS as compared to other media 

(such as television). Respondents in each location were also asked to interpret the meanings of 

several common safety and PSA messages (e.g., “Don’t drive impaired” and “Eyes on road, 

hands on wheel”). In general, most respondents had a fairly good understanding of these 

messages. 

Furthermore, the survey asked about safety and PSA messages that have a more threatening 

connotation. The majority of respondents indicated that such messages like “Click it or ticket or 
Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs 

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get $100 fine” or “100 deaths this year on Texas road,” would impact their driving behavior. In 

Chicago, respondents indicated that they would change their driving behavior for messages that 

relate to slowing down for emergency vehicles and in construction zones. Houston respondents 

indicated that messages that would most affect their driving are those with more assertive 

language (e.g., “Drunk driving, over the limit, under arrest”). Orlando motorists were most likely 

to change their driving behaviors for all safety and PSA messages; while, Philadelphia motorists 

were neutral on the effects of safety and PSA messages on their driving. 

In addition, the perceived usefulness of safety and PSA messages was examined in a binary logit 

model. The model showed that the messages were considered useful if the driver encountered 

them often. Respondents also thought that those messages could be effective in changing 

behavior. Hence, greater exposure to such messages impacts the perceptions of the messages. 

In three of the locations, drivers that considered driving under the influence (DUI) messages 

(Philadelphia, Chicago, Houston) and speeding messages (Orlando, Chicago, Houston) important 

also found safety and PSA messages to be useful. In two of the locations, individuals younger 

than 30 years old did not think that safety and PSA messages were useful. More factors that 

affect perceived usefulness were also mentioned, but they were on an individual city basis and 

are further discussed in CHAPTER 6: Findings and Recommendations/Guidance. 

Similarly, the perceived effectiveness was analyzed in a binary logit model, where all responses 

were aggregated together, ignoring locational factors. Safety and PSA messages were considered 

more effective when they were encountered often. They were considered useful for respondents 

older than 60 years old and respondents who had some graduate school or a post-graduate 

degree. Males with an income less than $25,000 per year and individuals younger than 30 years 

old did not perceive safety and PSA messages on DMS to be effective. 

There are limitations associated with this study as there are always sampling biases with surveys. 

To minimize such biases, a pilot test was conducted, a representative sample of the driving 

population was captured, and surveys were collected via face-to-face communication. A website 

was also set up to offer another mechanism for participants to answer the survey. Possible 

differences were also examined between those who lived in the general area of the city and those 

who did not. 

The general recommendation based on the surveys was that safety and PSA messages need to be 

considered useful and effective to maximize their influence on driver behaviors. Certain 

socioeconomic characteristics influence drivers’ perceptions of these messages. For instance, 

younger respondents were less likely to consider the messages effective, and future efforts 

should be focused on promoting awareness targeted toward this group. Respondents also 

indicated that they took assertive safety and PSA messages seriously, but further examination 

should consider the magnitude of this impact. 

Finally, drivers’ stated preferences usually differ from their revealed preferences. Thus, an onroad impact assessment of safety and PSA messages on DMS is needed to confirm the findings 

of this survey-based perceptional study. 
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CHAPTER 1. INTRODUCTION 

The number of transportation agencies that use DMS to provide traffic information to motorists 

has increased dramatically over the past four decades. According to the USDOT’s 2010 

deployment survey, almost 90 percent of freeway agencies and approximately 20 percent of 

arterial agencies reported using DMS to disseminate traveler information. This growing trend of 

DMS deployment is a reflection of the public interest in more information about travel 

conditions and the importance of traveler information for transportation system operations. 

Although extensive research has been conducted on traffic-related messages (see Dudek 1992; 

1997; and 2006 for examples),[1

]

 policies regarding the display and type of non-traffic-related 

messages vary greatly among states and, in some cases, are nonexistent. Therefore, it is unclear 

how effective these non-traffic-related messages are in modifying driver or travel behavior. It is 

also unclear whether these messages are acceptable to motorists and whether they have a positive 

or negative impact on their driving behavior (Tay and deBarros, 2010).[2

]

The purpose of this study is to identify how safety and PSA messages influence driver behavior. 

The findings from the study will help the USDOT, Transportation Management Centers Pooled 

Fund Study (TMC PFS) members, and state agencies and local transportation partners identify 

and implement the necessary improvements and changes to DMS technologies and safety and 

PSA messaging strategies in order to better support the public’s travel and safety needs.

The effectiveness of the messages is based on two primary factors: 

 Usefulness of the information disseminated. 

 Motorists’ ability to understand and willingness to use the information. 

The survey distributed to respondents did not define the terms “usefulness” or “effectiveness.” 

However, the survey was built under the assumption that most respondents spoke English and 

had an 8th grade education level. Therefore, it was assumed that a common interpretation in this 

context would be implied by all participants. Usefulness encompasses the practical and 

functional application of PSAs on DMS. Effectiveness is the perception that DMS would deliver 

safety and PSA messages such that a driver’s behavior would be positively impacted. 

Four urban areas in the United States were selected as study sites—Chicago, IL; Houston, TX; 

Orlando, FL; and Philadelphia, PA. Surveys were designed to specifically address the types of 

 

1 Dudek C.: Effective Message Design for DMS, TxDOT/FHWA 2006 

2 Tay R., deBarros A.: “Effectiveness of Road Safety Messages on Variable Message Signs,” Journal of Transportation 

Systems Engineering and Information Technology 01/201
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safety and PSA messages for each respective city. The goal was to collect approximately 500 

survey responses per city. In total, 2,088 responses were received. 
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CHAPTER 2. ORGANIZATIONAL AND INSTITUTIONAL FRAMEWORKS FOR 

SAFETY AND PSA MESSAGES IN THE FOUR URBAN AREAS 

This chapter identifies the organizational and institutional frameworks that govern the display of 

safety and PSA messages on DMS in each of the four urban areas—Chicago, Houston, Orlando, 

and Philadelphia.

CHICAGO 

In Illinois, jurisdiction over the creation and display of safety and PSA messages lies at the state 

and local levels. Typically, safety messages and PSAs will originate at the state level, while 

travel times, incident notifications, and construction notices will be generated at the local level. 

The Illinois Department of Transportation’s (DOT’s) Division of Traffic Safety, the State 

Secretary of Transportation, and the State Police all contribute to generating safety messages for 

display on DMS. The Secretary has insisted that the DMS show a count of highway-related 

deaths at all times, in addition to any travel times, incident notifications, construction notices, 

safety messages, and PSAs. The State Police and Division of Traffic Safety collaborate to create 

a list of safety messages and PSAs for display, usually corresponding to events of local or 

national significance. These messages are reviewed for conformance to the Manual on Uniform 

Traffic Control Devices (MUTCD). 

Over time, the usage of DMS has grown from solely displaying travel times to posting safety 

messages around holidays or other events associated with high traffic volumes, to now showing 

PSA and safety messages, travel times, and a count of highway-related deaths. This three-phase 

message set is displayed continuously. 

Moreover, the messages are displayed on all DMS in the Chicago area. There is no targeted 

demographic group; rather, the safety and PSA messages are aimed at the general traveling 

public. 

During an interview with an Illinois DOT representative, it was not specified how the capital, 

operation, and maintenance costs of Chicago’s DMS are funded. Presumably, these costs are 

covered through a combination of state and local funding. 

HOUSTON 

In general, safety messages are developed at the state level and then provided to regional TMCs 

for local dissemination at their discretion, based on traffic and other conditions. The 

development of the messages is based on Federal Highway Administration (FHWA) and state 

guidelines, and in part on national safety campaigns, while the localities have some feedback and 

input on which messages should be displayed. 
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Specific standards and guidance on DMS usage in the state of Texas can be found in Chapter 2I 

of the Texas MUTCD, 2011 version. Topics include applications, legibility and visibility, design 

characteristics, message length and units of information, and installation of permanent DMS. In 

general, the messages must be clear, concise, and easily understood by the public. 

Furthermore, the Texas Department of Transportation (TxDOT) primarily uses DMS for 

managing travel, controlling and diverting traffic, and identifying current and anticipated 

roadway conditions. Changes in roadway conditions include those due to traffic incidents, 

weather, and construction. Normally, TxDOT does not display messages that are basic traffic 

laws or could be considered “rules of the road.”

Travel times, construction notifications, emergency messages, and incident alerts have higher 

display priority than safety messages. During rush hours, only travel times are displayed, except 

for about 30 DMS on non-peak flow lanes that display safety messages. Outside of these times, 

and barring any incidents or construction, safety messages and PSAs are displayed continuously 

on all DMS in the Houston area. Usually, DMS are located sufficiently upstream of known 

bottlenecks, high crash locations, and major diversion decision points. 

Also, non-incident, traffic safety messages are displayed on a limited basis and must be 

associated with a specific targeted safety campaign. Non-traffic-related safety messages such as 

“Click it or ticket” and “Don't drink and drive” are displayed in conjunction with a media 

campaign. TxDOT has developed media tools for its traffic safety messages for use in television, 

radio, print ads, or news releases. These can also be part of national safety initiatives with 

support from the USDOT such as “Click it or ticket,” work zone awareness, and “No phone 

zone.” Through discussions with TxDOT, it was not clear how the construction, operation, and 

maintenance of DMS are funded, nor if the messages are targeted toward certain demographics. 

ORLANDO 

The display of safety messages is largely controlled at the state level, with some coordination 

with national safety campaigns. All messages displayed are for traffic information dissemination 

purposes. Due to a large number of requests, the state has developed guidance on safety and PSA 

message display. 

The default display on DMS is travel times, but this can be preempted by other messages 

conveying information on emergency events, traffic incidents, law enforcement alerts, or special 

events. In the absence of accurate or useful travel time information, and when not preempted by 

other messages, the DMS will display a safety message or PSA. 

As a compromise, safety messages are now shown in a limited fashion—presuming they have a 

positive effect on highway safety and congestion and the message is supplemental to a national 

or statewide highway safety media campaign. The total duration of any such campaign is limited 

to 2 hours per day during off-peak hours for a maximum duration of 2 weeks. Only six such 

events are allowed per year. The safety messages are posted to a select group of DMS deemed 
Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs 

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acceptable by the Florida Department of Transportation (FDOT). There are 18 DMS throughout 

the Orlando area, and local discretion is allowed for determining when to run the messages 

outside of peak hours. 

Funding for construction, operation, and maintenance of the DMS in Florida is provided by the 

state, with no federal contributions. 

PHILADELPHIA 

Control of the development and broadcast of safety messages occurs at the federal, state, and 

local levels in Pennsylvania. The state has issued formal guidance on this topic, Dynamic 

Message Sign Operating Standards, published in December 2013. The stated intent of the 

document is “to create uniformity in DMS messaging across Pennsylvania, yet provide flexibility 

for local needs.” Districts are encouraged to adopt these standards into their TMC’s standard 

operating procedures and develop pre-planned DMS response plans based on recurring events. 

Numerous sources were used by the Pennsylvania Department of Transportation (PennDOT) to 

develop the standards, including the national MUTCD, other state DMS guidelines, FHWA 

reports and directives, user comments, and the TMC PFS Changeable Message Sign Operation 

and Messaging Handbook. 

PennDOT’s engineering district offices have the ultimate responsibility for the operation and 

dissemination of messages via DMS on roadways within their jurisdictions. 

The state recommends prioritizing messages in the following order: 

1. Full road closure. 

2. Roadway restriction. 

3. Emergency destination guidance. 

4. AMBER alerts. 

5. Congestion. 

6. Weather/road conditions. 

7. Automated intelligent transportation system (ITS) messages. 

8. Special events. 

9. Future/planned events. 

10. Scheduled safety messages. 

11. Travel plaza messages. 

12. Sign testing. 

Travel times may be displayed in a two-panel fashion with any of the other types of message 

priorities listed. 
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Furthermore, particular guidance is provided for scheduled safety messages. The display of such 

messages may only be for a limited basis, is prohibited during peak traffic times (weekdays from 

6am to 9am and 3pm to 6pm), and can only be on DMS under the direct operation of district 

TMCs. All safety messages must be posted in accordance with the Scheduled Safety Message 

Calendar developed by PennDOT Central Office. Unless a DMS is being used to display a higher 

priority message, safety messages must be displayed on at least 50 percent of DMS. If the need 

arises, a District Traffic Engineer (DTE) can request an exemption to run a customized Local 

Safety Message in conjunction with the safety message calendar. 

Approved safety messages and a schedule for display are generated and distributed to the district 

TMCs each January. The four categories of safety messages include: 

1. Messages for a statewide safety campaign. 

2. Messages particular to a locality or region, which require DTE and Central Office approval. 

3. Messages in support of a new or existing traffic law, which must be vetted by the State Press 

Office. 

4. Messages on weather-related traffic laws. 

Also, the display of general PSAs is prohibited on DMS, along with messages related to 

advertising, routine congestion, contact information, and chronological information. 

Moreover, the interview with DOT staff in Philadelphia revealed that scheduled safety messages 

are displayed continuously at strategic locations during safety messaging operations campaign 

periods. Such locations may be after entry points with high traffic volumes. 

Funding and targeted demographics were not discussed during the interview with the 

PennDOT staff.
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CHAPTER 3. SURVEY DESIGN AND EXECUTION PLAN 

To successfully administer the surveys in all four locations and produce reliable and credible 

results, the project team developed a detailed survey design and execution plan that highlights 

the process for: 

 Identifying key safety and PSA messages for further evaluation. 

 Developing a clear, succinct, and customized survey questionnaire for each of the four 

urban areas. 

 Identifying the target population. 

 Calculating the sample size. 

 Collecting and analyzing the data. 

The remainder of this chapter further describes the survey design and execution plan in the four 

selected locations, as well as the pilot study. 

SURVEY DESIGN 

This section describes the approach to identifying key safety and PSA priority messages in each 

of the four test locations, the survey format, and the survey content. 

Priority Messages 

The project team researched and identified the type and content of safety and PSA messages that 

have been posted on DMS in the study areas (Chicago, Houston, Orlando, and Philadelphia). 

The team coordinated with the four state transportation agencies to gain information on the 

agencies’ policies, guidelines, and rules for displaying these safety and PSA messages on DMS. 

The team compiled: 

 A comprehensive list of safety and PSA messages that have been used by each state traffic 

management center, with an additional column indicating the frequency of use over the 

past year. 

 A recommended list of messages to use in the survey and the justification for the proposed 

messages. Based on input from stakeholders, proposed messages were suggested for further 

evaluation and inclusion in the survey. In addition, message consistency across the four 

regions was considered to provide a solid framework for comparison on the national scale. 
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Chicago 

Table 1 shows the final list of recommended priority messages for Chicago, based on 

conversations with the Illinois DOT. 

Table 1. Recommended messages for Chicago, IL. 

Priority Messages for Chicago, IL

Click It or Ticket

Don’t Drink and Drive

Move Over, Slow Down for Emergency Vehicles

Slow Down and Obey the Posted Speed Limit

Don’t Be a Distracted Driver

XXX Deaths This Year

Seat Belts Save Lives, Buckle Up

Don’t Text and Drive

Slow Down in Work Zones, Give ’em a Brake

Start Seeing Motorcycles

Construction Season Is Approaching – Give ‘em a Brake

Houston 

Priority messages for Houston were generated through interviews with TxDOT staff and the 

local Houston DOT/Transtar office. Table 2 presents the final list of recommended priority 

messages for Houston. 
Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs 

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Table 2. Recommended messages for Houston, TX. 

Priority Messages for Houston, TX

Click It or Ticket

Drive Safely, at or under the Speed Limit

Move Over or Slow Down, It’s the Law

Watch for Motorcycles, Drive Safely 

Drive Safely, Text Later, It Can Wait

XXX Deaths This Year on Texas Road

Drive Safely, Arrive Alive 

Use Caution in Work Zones

If Water on Road, Turn Around, Don’t Drown

Drink, Drive, Go to Jail

Orlando 

Table 3 presents the final list of recommended priority messages for Orlando. The messages 

were identified based on communications with FDOT staff. 

Table 3. Recommended messages for Orlando, FL. 

Priority Messages for Orlando, FL

Click It or Ticket

Prevent a Tragedy, Don’t Drink and Drive

Move Over for Emergency Vehicle, It’s the Law

Keep Safe Distance, Stay Safe

Drive Safely, Look Twice for Motorcycles

Don't Barrel Through Work Zones

Slow Down, Save a Life

Don’t Be a Distracted Driver

Report Impaired Drivers, Dial *347
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Philadelphia 

Based on discussions with PennDOT staff in Philadelphia, a list of priority messages for 

Philadelphia was identified. Table 4 presents the final list of recommended priority messages 

for Philadelphia. 

Table 4. Recommended messages for Philadelphia, PA. 

Priority Messages for Philadelphia, PA

Click It or Ticket

Steer Clear of Emergency Responders, It’s the Law

Stay Right, Pass Left, It’s the Law

Slow Down, Save a Life 

Eyes on Road, Hands on Wheel

Drive Sober or Get Pulled Over

Watch for Motorcycles, Drive Safely

Avoid Aggressive Driving

Stay Safe, Don’t Drive Impaired

Survey Format 

The surveys included demographic information (e.g., age, gender, income) as well as questions 

on behavior, acceptance, and comprehension. Paper and online surveys were used for 

enhanced outreach: 

 The four-page, tri-fold paper-based survey had an imprinted postage-paid address so it could 

be easily returned by mail. This ensured that the survey could be completed and returned 

easily and quickly. In addition, the paper-based survey included a link to a web-based survey 

for those participants wishing to complete the questionnaire online. 

 The web-based survey had questions that were identical to the paper-based survey and 

accessible through any Internet connection. Respondents were given an opportunity to 

preview, go backwards, and change answers. Once completed and submitted, respondents 

received a confirmation. 

Both surveys allowed respondents to skip questions that they did not feel comfortable answering. 
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Survey Questionnaire/Content 

The survey design was based on the priority safety and PSA messages that were identified based 

on suggestions from state agencies in each of the four studied urban areas and that were reviewed 

by the PFS members. The surveys attempted to accurately depict the weaknesses and strengths of 

the system and any areas of improvement by gathering input from system users that have been 

exposed to those safety and PSA messages on DMS. 

The survey questions were clear, succinct, simple to answer, and able to be completed in 15 

minutes or less. Appendix A: Survey Questionnaires provides a complete set of the administered 

survey questionnaires. 

To achieve a 95-percent confidence level, 500 surveys needed to be returned per site. In total, 

2,088 responses were received. 

SURVEY EXECUTION 

This section describes the approach for administering the survey in all four sites. This includes 

the recruitment of potential respondents and locations for face-to-face delivery of the surveys. 

Subject Recruitment 

For the purposes of this study, the project team targeted drivers who may have encountered DMS 

with safety and PSA messages. Drivers included local residents and out-of-town travelers. The 

following survey administration techniques were considered: 

1. Utilization of vehicle registration/licensing information. 

2. In-person delivery of survey questionnaire. 

3. Posting the surveys online. 

Despite the anticipated effectiveness of Technique 1: Utilization of Vehicle 

Registration/Licensing Information, it raises privacy and technical concerns for some agencies 

(such as the Florida, Illinois, and Pennsylvania DOTs). Therefore, a combination of Techniques 

2 and 3 was used to obtain the largest sample size in the most cost-effective and timely manner. 

Appendix B: Sample Size Calculation provides details on the sample size calculation. 

Survey Locations for In-Person Interviews 

The team selected 18 potential survey locations across the four selected cities (Philadelphia, 

Houston, Orlando, and Chicago) for distribution of the surveys. 
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Appendix C: Potential Survey Locations by City provides a list of these potential locations. 

Prior to selecting the potential survey locations, the team conducted research to locate all DMS 

locations for each city. In most cases, these DMS locations are available online via local or state 

DOT websites. In cases where DMS locations were not available online, the project team 

reached out to the state DOT for a list of these locations. The lists were then used to map all of 

the DMS locations across the four cities. 

In most cases, DMS are located along freeway and arterial routes in all four cities. Using the 

DMS map that was created, the team began to look for suitable locations to conduct the survey. 

Survey locations were selected based on type of facility. Emphasis was placed on finding 

facilities that would contain a high rate of commuter traffic that would have potentially passed a 

DMS sign en route to the location. For this reason, facilities such as park-n-ride lots, transit 

stations, rest stops, gas stations, and shopping centers were considered ideal locations due to 

their expected rate of commuter traffic and high turnover, which is thought to provide a larger 

audience for survey distribution. Facilities were then narrowed down based on their proximity to 

a DMS. Only those facilities that had at least one DMS within a 2-mile radius of the site were 

considered for a potential survey location. 

Once suitable facilities were found, the team then catalogued the facilities based on the number 

of parking spaces, where applicable, and the average daily traffic (ADT) of the freeway/arterial 

closest to the facility in an effort to illustrate the potential audience capture for the survey at 

each location. 

PILOT STUDY 

The project team conducted a live, face-to-face pilot in Philadelphia and developed web-based 

surveys for Chicago, Houston, and Orlando to test the survey instrument in advance of the final 

survey implementation. The purpose of the pilot testing was to validate the survey and ensure 

that the sampled population would understand the wording, order of questions, and template. The 

pilot study included administering the survey to a small sample, coding the data, and performing 

descriptive analyses of the data. Some preliminary statistics were needed to examine the 

variability across several of the key dependent variables, as the initial goal of the pilot survey 

was to assess statistical proportions and variations since they can vary greatly depending on the 

specific behavior (or driver/travel characteristic) being considered (e.g., proportion that will 

change seat belt usage, change route, or slow down). 

Live In-Person Survey 

The live pilot survey was conducted in the Philadelphia area on Thursday, March 7, 2013, from 

2:00 pm to 4:00 pm at the I-95 Pennsylvania Welcome Center. 

The I-95 Pennsylvania Welcome Center was selected due to its known proximity to a DMS 

location, with the closest DMS approximately 0.5 mile south of the Welcome Center on I-95
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Northbound, as shown in Error! Reference source not found.. The Welcome Center is a 

limited-access facility, with the only access to the site from I-95 Northbound where the DMS 

was located. This guaranteed that all traffic arriving at the Welcome Center had passed the DMS 

immediately before arriving. The team selected a 2-hour afternoon slot in an effort to capture 

travelers prior to the evening rush hour, when traffic flow may impede access to the Welcome 

Center and thereby potentially decrease the survey audience. 

The project team coordinated with the Welcome Center staff in this city to set up a table inside 

the Welcome Center for the survey. This table was staffed near the entrance to the building, 

where travelers were approached to fill out the survey as they entered. Twenty-five surveys were 

completed during the pilot survey time period. 

Figure 1. Photo. Pilot survey location. 

Survey Results 

The survey was given to 25 participants, with an age range from 23 to 84 years old, and a mean 

age of 47 years old (S.D. = 18.45 years). Thirty-two percent of the participants shared a 

household with one or more persons. Only 2 out of the 25 participants have children under the 

age of 6. Forty-four percent of the participants own their own a home. Twenty-four percent of 

the participants have high school as their highest education; 28 percent of the participants have 

graduate or post-graduate degrees (Table 5). The median household income is between $25,000 

and $50,000 per year (Table 6).
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Table 5. Educational level of study participants. 

Highest Level of Education %

Some Schooling 8

High School 24

Associate Degree 8

Undergraduate 8

Graduate 12

Postgraduate 16

Table 6. Household income in $/year of study participants. 

Household Income %

Less than $25,000 12

$25,001 to $50,000 32

$50,001 to $75,000 12

$75,001 to $100,000 8

$100,001 to $125,000 8

Greater than $125,000 3

The survey showed that some messages on the highway are more recognized than others. Sixty 

percent or more of the participants recognized the followings PSAs: “Buckle up, seat belts save 

lives,” “Click it or ticket,” “Live free, ride alive,” and “Steer clear of emergency responders, it’s 

the law.” Other messages did not get as much attention and were recognized within a range of 20 

to 40 percent. Further answers to questions indicated that, in general, most survey participants 

have encountered DMS on the highway in the past (Error! Reference source not found.). Only 

4 out of 25 participants stated that they have rarely or never seen one. 
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Figure 2. Chart. Recognition of PSA messages. 

Forty percent of the participants strongly agree that there is a high level of police enforcement in 

all categories including seat belt use, speeding in a work zone/construction area, speeding over 

the posted speed limit, DUI, texting or using a mobile device while driving, tailgating (or 

following too close to another vehicle), and using the left lane for regular driving (not passing). 

No participant disagrees or strongly disagrees with that statement (Table 7). 

Figure 1. Recognition of PSA messages.
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Table 7. Level of enforcement. 

Activity Strongly 

Agree Agree Neutral Disagree Strongly Disagree

Seat belt use 16 6 0 0 0

Speeding in a work zone/construction 

area

10 11 0 0 0

Speeding over the posted speed limit 12 10 0 0 0

DUI 17 5 0 0 0

Texting or using a mobile device 

while driving 13 9 0 0 0

Tailgating (or following too close to 

another vehicle) 18 4 0 0 0

Using the left lane for regular driving 

(not passing) 16 6 0 0 0

Other general reckless behaviors not 

already described in A to G 16 5 0 0 0

Forty percent of the participants always respond to the dynamic messages they see. The most 

recognized DUI warning message is “Drive sober or get pulled over,” with 12 out of 25 

participants always responding to this message (Table 8). 

Table 8. Would you change your driving behavior when you see the listed PSAs? 

Activity Never Rarely Sometimes Often Always

Buckle your seatbelt if it was not buckled

...for “Click it or ticket” 1 1 8 2 10

Remember to stay at or below the speed 

limit 

...for “Slow down, save a life”

1 3 6 5 6

Put away your mobile phone while driving

...for “Don’t drive distracted” 1 2 8 3 7

Slow down

...for “Steer clear of emergency 

responders, it’s the law”

1 2 4 5 10

Not drink or do drugs

...for “Drive sober or get pulled over”

0 2 6 2 12

Be more aware of motorcycles

...for “Watch for motorcycles, drive 0 1 7 5 9
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Activity Never Rarely Sometimes Often Always

safely”

Only 8 percent of the participants strongly disagree to change their driving patterns or habits 

based on the listed PSA messages. On the other hand, the majority of the participants responded 

that they would “agree” or “strongly agree” to change their driving behavior. Most participants 

agreed with the message “Click it or ticket” (48 percent) and would change their driving patterns 

based on that message (Table 9). 

Table 9. Whether to change driving patterns or habits based on the following PSAs. 

Message Strongly 

Agree Agree Neutral Disagree Strongly Disagree

Click it or ticket 12 5 1 0 2

Steer clear of emergency responders, 

it’s the law 10 7 1 0 2

Stay right, pass left, it’s the law 9 8 1 0 2

Slow down, save a life 9 7 1 0 2

Eyes on road, hands on wheel 8 10 1 0 2

Drive sober or get pulled over 9 8 1 0 2

Watch for motorcycles, drive safely 7 11 1 0 1

Stay safe, don’t drive impaired 9 8 1 0 2

Seventy-six percent of the participants “strongly agree” or “agree” that PSAs that show a fine 

will impact their driving behavior. At the same time, 48 percent of the participants “agree” or 

“strongly agree” that they are uncomfortable reading threatening messages while driving. 

Two participants out of 25 have been involved in a collision that was reported to the police in 

the past 5 years, and four have received one ticket for a moving violation (Figure 3). This 

proportion helped in verifying that the pilot study captured a realistic and representative sample 

of the population. 
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Figure 3. Chart. Number of collisions and number of ticket instances in the past 5 years. 

LESSONS LEARNED FROM THE PILOT SURVEY 

The pilot study resulted in several key lessons learned in relation to the survey administration 

and execution plan: 

 The pilot survey was conducted without incentive, and the response rate was 95 percent for 

all persons approached. However, several comments were made about the survey length—

even at a rest stop, many people were not willing to spend 10 minutes to complete the full 

survey and left some pages or questions blank. An incentive such as printed coupons was 

worth providing to ensure high participation in the final survey. 

 A highway rest stop was found to capture an audience primarily of travelers, not locals. 

Efforts were made to select multiple locations for the final survey to spread contact over all 

traveler populations. 

 Coordinating with local officials (such as local DOTs, operators of facilities, etc.) prior to 

conducting surveys is crucial to ensure that all jurisdictions are aware of the team’s

operations for a successful survey experience. This also helps in marketing the survey—

during the pilot survey, the rest stop personnel were helpful in marketing the survey to all 

groups that came into the parking lot, before they entered the building. 

 There was a segment of the pilot survey population that had never seen a DMS, had never 

seen some of the PSA messages, or did not understand the meaning of several of the 

messages, and asked the survey administrator for explanations. It is helpful to have additional 

literature or a web link available to provide more information. 
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CHAPTER 4. ADJUSTMENTS TO THE SURVEY EXECUTION PLAN 

This chapter captures the adjustments to the survey execution plan that were made based on the 

lessons learned during the pilot study. It provides the final execution plan for the administration 

of the full surveys in the four target urban areas.

FINAL DATA COLLECTION LOGISTICS 

The project team conducted in-person surveys in the four cities chosen for this study (Houston, 

Philadelphia, Orlando, and Chicago) from September 2013 through November 2013. Potential 

survey sites were selected for each city prior to travel based on a variety of factors including 

proximity to DMS locations, high rate of pedestrian and vehicle traffic to target for surveys, 

FHWA and the PFS recommendations, and success rates of similar types of studies in prior 

cities. A survey team of three staff members was deployed to each city for 3 days; multiple sites 

were visited and multiple administration techniques were tested. Based on the sample size 

calculations conducted prior to survey administration, a goal was set to achieve at least 500 

survey responses in each city to meet a 95-percent confidence interval. This section details the 

evolution of site selection across the four cities. 

Houston 

Houston was selected as the first city to survey between September 18 and September 21, 2013. 

Table 10 lists the original survey locations selected for Houston by the project team. These 

original locations were presented to the FHWA and TMC PFS members for review. The project 

team revised the potential survey locations (see Table 11) based on the comments received. 

Table 12 details the locations ultimately visited by the survey team on the first trip to Houston, 

including the date and time of each site visit. During the first visit, the survey team focused 

largely on surveying shopping malls, universities, and public gathering spaces. Surveys were 

distributed for immediate response as well as for mail-back response via a postage-paid 

printed survey. At the end of the 3-day study period, the survey team returned with 140 

completed surveys. 

Houston was visited a second time between November 14 and November 16, 2013, to increase 

the number of survey responses. Table 13 details the locations visited during the second visit. 

The second visit resulted in 430 survey responses, bringing the total survey responses to 570 

for Houston. 
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Table 10. Original Houston survey locations. 

Location Address Type of Facility

Northwest Transit Center 7373 Old Katy Rd. Park-n-Ride for Houston Metro Bus

Eastex Park-n-Ride 14400 Old Humble Rd. Park-n-Ride for Houston Metro Bus

Fannin South Park-n-Ride 1604 West Bellfort Rd.

Park-n-Ride for Houston Metro Bus 

and Metro Rail 

Fuqua Park-n-Ride 11755 Sabo Rd. Park-n-Ride for Houston Metro Bus

Gulfgate Transit Center 7400 South Loop East Park-n-Ride for Houston Metro Bus

Table 11. Updated Houston survey locations based on state DOT feedback. 

Location Address Type of Facility

Willowbrook Mall 2000 Willowbrook Mall Rd. Shopping Mall

The Galleria 5085 Westheimer Rd. Shopping Mall

University of Houston 4800 Calhoun Rd. University

Northwest Transit Center 7373 Old Katy Rd.

Park-n-Ride for Houston Metro 

Bus

Gulfgate Transit Center 7400 South Loop East Park-n-Ride for Houston Metro 

Bus
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Table 12. Survey locations visited in Houston during first visit. 

Location Address Type of Facility Date 

Visited

Time 

Visited

University of Houston 4800 Calhoun Rd. University 09/18/13 11:00am2:00pm

Hermann Park 6201 Hermann 

Park Dr.

Outdoor Park/Central 

Gathering Area 09/18/13 4:00pm7:00pm

Rice University 6100 Main St. University 09/19/13 11:00am2:00pm

The Galleria 5085 Westheimer 

Rd.

Shopping Mall 09/19/13 3:00pm7:00pm

South Shore Harbour 

Conference 

Center/Hotel

2500 South Shore 

Blvd.

Hotel / Conference 

Center 09/20/13 9:00am11:00am

Willowbrook Mall

2000 

Willowbrook Mall 

Rd.

Shopping Mall 09/20/13 12:00pm3:00pm

Kemah Boardwalk 215 Kipp Ave. Shopping/Dining 09/20/13 4:00pm7:00pm

Houston Hobby 

Airport

7800 Airport 

Blvd.

Airport 09/21/13 9:00am2:00pm

Table 13. Survey locations visited in Houston during second visit. 

Location Address Type of 

Facility

Date 

Visited

Time 

Visited

Bush Intercontinental Airport 

(IAH) Cell Phone Waiting Lot 1 JFK Blvd. Airport Waiting Lot

11/14/13 –

11/15/13

11:00am5:00pm

IAH Cell Phone Waiting Lot 2 Will Clayton 

Parkway

Airport Waiting 

Lot

11/14/13 –

11/15/13

11:00am5:00pm

Kuykendahl Park-n-Ride 12920 

Kuykendahl Rd.

Park-n-Ride for 

Houston Metro 

Bus

11/15/13 6:00am9:00am

Houston Community College 

Northeast

555 Community 

College Dr.

Community 

College 11/16/13 10:00am2:00pm
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Figure 4. Photo. Houston survey sites. 

Philadelphia 

Philadelphia was selected as the second city to survey between October 10 and October 12, 

2013. Using lessons learned from Houston, the survey team updated selected survey locations to 

those that would be more successful for gathering immediate responses from participants. Table 
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14 through Table 16 detail the progression of site selection for Philadelphia. At the end of the 3-

day study period, the survey team returned with 504 completed surveys. 

Table 14. Original Philadelphia survey locations. 

Location Address Type of Facility

I-95 PA Welcome 

Center

1⁄2 mile from PA/DE 

Border on I-95 Highway Rest Stop

30th St Station 93 N. 30th St. and Market 

St.

Parking Lot for Multiple Regional Rail 

Lines, Amtrak, NJ Transit Bus Routes

Penn’s Landing 

Parking Lot

Intersection of Columbus 

Blvd at South St.

Parking Lot for SEPTA Bus Routes 

Wissahocken SEPTA 

Station

5099 Ridge Avenue and

Osborn St.

Parking Lot for SEPTA Station

Table 15. Updated Philadelphia survey locations based on state DOT feedback. 

Location Address Type of Facility

I-95 PA Welcome 

Center

1⁄2 mile from PA/DE 

Border on I-95 Highway Rest Stop

30th St Station 93 N. 30th St. and Market 

St.

Parking Lot for Multiple Regional Rail 

Lines, Amtrak, NJ Transit Bus Routes

King of Prussia Mall 160 N. Gulph Rd. Shopping Mall

Cornwell Heights 

SEPTA Station 700 Station Ave. SEPTA Station / Park-n-Ride Lot

Franklin Mills Mall 1455 Franklin Mills Circle Shopping Mall
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Table 16. Survey locations visited in Philadelphia. 

Location Address Type of Facility Date 

Visited

Time 

Visited

30th St Station 93 N. 30th St. 

and Market St.

Parking Lot for Multiple 

Regional Rail Lines, Amtrak, 

NJ Transit Bus Routes

10/10/13 –

10/11/13

9:00am11:00am

and

2:00pm5:00pm

Drexel 

University

3141 Chestnut 

St. University 10/10/13 11:00am2:00pm

University of 

Pennsylvania 3451 Walnut St. University 10/11/13 11:00am2:00pm

Columbus St 

DMV

1530 S. 

Columbus Blvd.

Department of Motor 

Vehicles 10/11/13 9:00am10:00am

Reading 

Terminal Market 51 N. 12th St. Shopping/Dining 10/12/13 11:00am4:00pm
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Figure 5. Photo. Philadelphia survey sites. 
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Orlando 

Orlando was selected as the third city to survey between October 17 and October 19, 2013. Table 

17 through Table 19 detail the progression of site selection. At the end of the 3-day study period, 

the survey team returned with 500 completed surveys. 

Table 17. Original Orlando survey locations. 

Location Address Type of Facility

Turkey Lake Service Plaza Mile Post 263 - Florida 

Turnpike Highway Rest Stop 

Orange County Convention 

Center 9400 Universal Blvd. Convention Center – would focus on intercepting in parking lots

Orlando Amtrak Station 1400 Sligh Blvd. Train Station

Econlockhatchee Park-n-Ride 9555 East Colonial Dr. Park-n-Ride Lot

Table 18. Updated Orlando survey locations based on state DOT feedback. 

Location Address Type of Facility

Turkey Lake Service Plaza Mile Post 263 - Florida 

Turnpike Highway Rest Stop 

Orange County Convention 

Center 9400 Universal Blvd. Convention Center 

Florida Mall 8001 S Orange Blossom Trail Shopping Mall

The Mall at Millenia 4200 Conroy Rd. Shopping Mall

University of Central Florida 4000 Central Florida Blvd. University
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Table 19. Survey locations visited in Orlando. 

Location Address Type of Facility Date Visited Time Visited

Turkey Lake 

Service Plaza

Mile Post 263 -

Florida Turnpike

Highway Rest 

Stop 

10/17/13 -

10/18/13

8:00am11:00am

University of 

Central Florida

4000 Central 

Florida Blvd.

University 10/17/13 –

10/18/13

11:00am2:00pm

Orange County 

Convention 

Center

9400 Universal 

Blvd.

Convention 

Center 10/18/13 2:00pm5:00pm

Universal City 

Walk

6000 Universal 

Blvd.

Shopping/Dining 10/18/13 6:00pm9:00pm

Orlando 

International 

Airport

1 Jeff Fuqua Blvd. Airport 10/19/13 9:00am1:00pm
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Figure 6. Photo. Orlando survey sites. 
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Chicago 

Chicago was selected as the fourth city to survey between November 6 and November 9, 2013. 

Table 20 through Table 22 detail the progression of site selection. At the end of the 3-day study 

period, the survey team returned with 584 completed surveys. 

Table 20. Original Chicago survey locations. 

Location Address Type of Facility

Cumberland Park-nRide 5800 N. Cumberland Ave. Park-n-Ride Lot for “L” Train Blue 

Line Train and CTA Buses

LaSalle St Station 121 W. Van Buren St.

Parking Lots for Several “L” Train 

Lines (Brown, Orange, Pink, and

Purple Lines) 

Garfield Red Line 

Station 220 W. Garfield Blvd. Parking Lot for “L” Train Red Line and CTA Buses

Shell / BP Gas Station Intersection of W. Touhy Ave.

and N. Cicero Ave.

Gas Station

Target Shopping Center Intersection of Harrison St. and 

S. Manheim Rd.

Shopping Center

Table 21. Updated Chicago survey locations based on state DOT feedback. 

Location Address Type of Facility

Garfield Red Line 

Station 220 W. Garfield Blvd. Parking Lot for “L” Train Red Line and CTA Buses

Shell / BP Gas 

Station 

Intersection of W. Touhy Ave 

and N. Cicero Ave.

Gas Station

Target Shopping 

Center

Intersection of Harrison St. and 

S. Manheim Rd.

Shopping Center

Gurnee Mills Mall 6170 W. Grand Ave. Shopping Mall

Woodfield Mall 5 Woodfield Mall Rd. Shopping Mall

Millenium Park S. Columbus Dr. Outdoor Park/Central Gathering Area
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Table 22. Survey locations visited in Chicago. 

Location Address Type of Facility Date 

Visited

Time 

Visited

Chicago Union Station Canal St. Central Station for 

Amtrak and Metra

11/06/13 -

11/07/13

8:00am2:00pm

University of Chicago 5555 S Ellis Ave. University 11/08/13 11:00am2:00pm

Chicago Central DMV 100 W. Randolph St. DMV 11/07/13

2:00pm5:00pm

Millennium Park S. Columbus Dr.

Outdoor 

Park/Central 

Gathering Area

11/09/13 9:00am1:00pm

O’Hare International 

Airport

1000 West O’Hare 

Ave.

Airport 11/09/13 3:00pm6:00pm
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Figure 7. Photo. Chicago survey sites. 
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CHAPTER 5. RESULTS AND ANALYSIS 

DESCRIPTIVE STATISTICS

After incomplete surveys were removed, there were 497 usable surveys from Philadelphia, 500 

from Orlando, 584 from Chicago, and 507 from Houston. This chapter includes descriptive 

statistics in numerical (i.e., means, standard deviations, min, max) and graphical forms (i.e., box 

plots, histograms, scatter plots) of these surveys. The specific display depends on the response 

type for the question being analyzed (i.e., continuous, categorical, or ordinal). Table 23 presents 

a breakdown of the demographics for individual respondents. 

Table 23. Demographics by survey city. 

Philadelphia 

(n=497)

Orlando 

(n=500)

Chicago 

(n=584)

Houston 

(n=507)

Gender

Female 260 217 274 244

Male 202 223 269 233

Age (years)

Range 17-85 16-91 16-82 17-85

Mean (SD) 30.18 (15.0) 29.04 (13.01) 36.83 (15.9) 32.18 (15.4)

Marital Status

Single 274 266 258 216

Significant Other 59 53 59 30

Married 106 83 166 196

Divorced 21 26 48 28

Highest Education

Some Schooling 9 37 14 33

High School Diploma 160 171 159 187

Associate Degree 47 98 86 76

Undergrad Degree 148 68 151 96

Some Grad School 34 23 44 32

Post Grad Degree 55 16 76 34

English as Primary Language

Yes 407 258 489 83

No 49 142 43 385

There was roughly an equal number of males and females at each site, as well as a similar 

distribution in ages across locations. Most of the respondents were primarily English speakers. 

Table 24 summarizes the self-reported information about the subjects’ driving experiences. These 

results are highly representative of normal driving populations, where most respondents have not 
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been involved in a collision or received a moving violation within the past 5 years. From the 

drivers who had been involved in a collision or moving violation, the average was two or less 

respective instances, observed at each city. 

Table 24. Driving experience by survey city. 

Philadelphia 

(n=497)

Orlando 

(n=500)

Chicago 

(n=584)

Houston 

(n=507)

Collision (within 5 years)

No 371 361 433 395

Yes 90 64 103 74

If Yes, How Many

Mean (SD) 1.22 (0.29) 1.66 (0.96) 1.12 (0.36) 1.19 (0.48)

Moving Violation (within 5 years)

No 367 353 393 379

Yes 92 60 147 96

If Yes, How Many

Mean (SD) 1.64 (1.54) 1.61 (0.93) 1.71 (1.35) 2.06 (1.78)

Table 25 provides information on household demographics. The majority of participants lived 

within the greater area of the respective survey’s city. Each city had a similar range and mean in 

household size. The distribution of household incomes across all cities was also very similar. 

Drivers who own and rent their living space are each well represented in all cities. 
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Table 25. Socioeconomic characteristics of the survey respondents. 

Philadelphia 

(n=497)

Orlando 

(n=500)

Chicago 

(n=584)

Houston 

(n=507)

Live within Greater Area

Yes 308 248 317 356

No 153 159 218 113

People in House

Range 1-20 1-20 1-20 1-26

Mean (SD) 3.3 (2.18) 3.2 (1.69) 3.2 (1.88) 3.5 (2.17)

Children under 6 in Household

Count 39 108 91 101

Range (if yes) 1-6 1-5 1-4 1-15

Current Living Space

Rent 220 211 203 152

Own 136 100 220 215

Neither 101 106 109 106

Household Income

< 25k 109 149 101 82

25k - 50k 85 125 124 112

50k - 75k 83 82 117 88

75k - 100k 73 37 58 57

100k - 125k 27 15 51 28

> 125k 55 10 50 59

Interpretations of PSAs 

Each city was asked to interpret three potential PSAs that were relevant to their city with some 

overlapping questions for comparison. Not all messages were used in all four cities; however, for 

consistency, exactly three interpretation questions were asked in each city (Q4, Q5, and Q6). For 

Philadelphia, Orlando, and Chicago, the respondents were asked for their interpretation of the 

PSA: “Ride safely, sober, live free, ride alive.” This information was not solicited for Houston, 

because there was no similar PSA message on DMS in the city at the time the survey was 

administered (the questions used in the survey were discussed and approved at an earlier 

stakeholders meeting). With respect to the PSA, “Ride safely, sober, live free, ride alive,” there 

was a generally shared interpretation across the three cities sampled that this message meant, 

“Don’t drink and drive,” as shown in Figure 8 (a) (b) and (c). 
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Figure 8 (a) (b) (c). Chart. PSA “ride safely, sober, live free, ride alive.”

These same three cities were also surveyed on their interpretation of the PSA: “Eyes on road, 

hands on wheel.” A comparison of these results is provided in Figure 9 (a) (b) and (c). There was 

a split in the understanding of this PSA message between “Stay alert” and “Don’t drive 

distracted,” observed in all three cities. 
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Figure 9 (a) (b) (c). Chart. PSA “eyes on road, hands on wheel.”

All four cities were surveyed on an individual PSA commonly viewed in their area, which was 

also comparable across all cities. The overall message for this PSA was safety, with variations in 

focus highlighting motorcycle and impairment awareness. For Philadelphia and Houston, the 

term “motorcycle safety” was included; in Houston, Chicago, and Orlando, the term 

“impairment” was used; and in Orlando and Houston, “ride” was included to allude to 

motorcycle drivers. Figure 10 (a) (b) (c) and (d) illustrate the comparison of interpretations based 

on these word choices. 
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Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs 

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Figure 10 (a) (b) (c) (d). Chart. Comparable PSA messages by city. 

Houston was also surveyed on two additional PSA messages: “Don’t barrel through work zones” 

and “Avoid aggressive driving.” The interpretations of these messages can be viewed in Figure 

11 (a) and (b). For the most part, participants agreed on the meanings of these messages. 

 
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Figure 11 (a) (b). Chart. Additional PSA messages in Houston. 

Each city was also given a list of approximately 15 of the most commonly posted PSA messages 

for their area, and participants were asked to select all messages that they recognized. Figure 12

(a) (b) (c) and (d) show the top 10 most recognized PSAs for each city. Seatbelt campaigns were 

most widely recognized across all four areas. 

39.1 34.7 28.6 26.6 26.6

(Percent)

Use caution in work zonesYou talk, you text, you crashDrunk driving, over the limit, under arrestMove over or slow down, it's the lawDrive sober or get pulled over

62.8 56.1 50.5 47.3 36.6 36.4 23.9 19.1 18.7 16.9

Philadelphia (Percent) 0 100 200 300 400 500

Click it or ticketBuckle up, seat belts save livesDrive safelySlow down, save a lifeWatch for motorycles, drive safelyDrive sober or get pulled overAvoid aggressive drivingStay right, pass left, it's the lawBuckle up, just do itEyes on road, hands on wheel

38.2 37 34.2 34 33

Slow down & obey the posted speed limitNo excuses, buckle upReport impaired drivers, dial *347Drive safely, look twice for motorcyclesMove over for emergency vehicle, it’s the law

77.9 57.9 51.5 49.7 37 35.6 34.1 26.5 23.8 19

Count

0 100 200 300 400 500

Click it or ticketAlways wear your seat belt, it's the lawSeat belts save lives, buckle upYou drink & drive, you loseConstruction season is approaching, drive safelyMove over, slow down for emergency vehiclesDon't drink & drive, report all DUI driversWinter season is quickly approachingSlow down & obey the posted speed limitDUI drivers will be arrested & prosecuted
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79.9 77.7 53.6 48.5 43.2 39.1 34.7 28.6 26.6 26.6

Houston (Percent)

C

0 100 200 

Click it or ticketDrink, Drive, Go 100 deaths this yBuckle up, every Drive safely, text Use caution in wYou talk, you texDrunk driving, oveMove over or sloDrive sober or ge

62.8 56.1 50.5 47

P

0 100 200 

Click it or ticketBuckle up, seat Drive safely

68.6 60.4 46 41.2 41 38.2 37 34.2 34 33

Orlando (Percent)

Count

0 100 200 300 400 500

Click it or ticketBuckle up, seat belts save livesBuckle up, save livesDUI decide before you driveBuckle up, just do itSlow down & obey the posted speed limitNo excuses, buckle upReport impaired drivers, dial *347Drive safely, look twice for motorcyclesMove over for emergency vehicle, it’s the law

77.9 57.9 51.5 49

Count

0 100 200 300 400 500

Click it or ticketAlways wear your seat belt, it's the lawSeat belts save lives, buckle up

39.1 34.7 28.6 26.6 26.6

(Percent)

Use caution in work zonesYou talk, you text, you crashDrunk driving, over the limit, under arrestMove over or slow down, it's the lawDrive sober or get pulled over

62.8 56.1 50.5 47.3 36.6 36.4 23.9 19.1 18.7 16.9

Philadelphia (Percent) 0 100 200 300 400 500

Click it or ticketBuckle up, seat belts save livesDrive safelySlow down, save a lifeWatch for motorycles, drive safelyDrive sober or get pulled overAvoid aggressive drivingStay right, pass left, it's the lawBuckle up, just do itEyes on road, hands on wheel

38.2 37 34.2 34 33

(Percent)

Slow down & obey the posted speed limitNo excuses, buckle upReport impaired drivers, dial *347Drive safely, look twice for motorcyclesMove over for emergency vehicle, it’s the law

77.9 57.9 51.5 49.7 37 35.6 34.1 26.5 23.8 19

Chicago (Percent)

Count

0 100 200 300 400 500

Click it or ticketAlways wear your seat belt, it's the lawSeat belts save lives, buckle upYou drink & drive, you loseConstruction season is approaching, drive safelyMove over, slow down for emergency vehiclesDon't drink & drive, report all DUI driversWinter season is quickly approachingSlow down & obey the posted speed limitDUI drivers will be arrested & prosecuted
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Figure 12 (a) (b) (c) (d). Chart. Top 10 most recognized PSAs by city. 

A possible correlation between these top 10 most recognized messages by respondents and the 

actual count/duration of message displays in each urban area was examined. However, limited 

data was available from each jurisdiction, and a robust correlation could not be identified. 

Data was obtained from the TxDOT for these top 10 messages in Houston for the 3 months 

leading up to the study and the study month itself. “Drink, drive, go to jail” was displayed 167 

times in each of the 3 months prior to the survey. “XX deaths this year on Texas roads” was

displayed 165 times in each of the 4 months. “Buckle up, every rider, every ride” was displayed 

165 times in the month of collection. “Move over or slow down, it’s the law” was displayed 167 

times in one of the three preceding months and “Drive sober or get pulled over” twice in two of 

the preceding months. 

Chicago reported displaying death count messages 24/7, alternated with one PSA message. The 

alternative messages were: “Cell phone use while driving must be hands free,” “Don’t drink and 

drive,” “Don’t text and drive,” “Save a life, buckle up,” and “Stay off the phone in work zones.” 

Philadelphia did not display any of the top 10 recognized messages in the 4 months of interest. 

However, this is based on exact wording, and it is unclear whether a similar variation of a 

message was displayed. Data on the Orlando PSA display schedule for the time of this study was 

unable to be linked with any significance. 

All four cities were asked general questions about their experiences and opinions regarding 

posting PSAs on DMS. Table 26 provides a summary of responses on frequency, usefulness, and 

effectiveness of these messages. 

79.9 77.7 53.6 48.5 43.2 39.1 34.7 28.6 26.6 26.6

Houston (Percent)

Count

0 100 200 300 400 500

Click it or ticketDrink, Drive, Go to jail100 deaths this year on Texas roadBuckle up, every rider, every rideDrive safely, text later, it can waitUse caution in work zonesYou talk, you text, you crashDrunk driving, over the limit, under arrestMove over or slow down, it's the lawDrive sober or get pulled over

62.8 56.1 50.5 47

P

0 100 200 300 400 500

Click it or ticketBuckle up, seat belts save livesDrive safely

68.6 60.4 46 41.2 41 38.2 37 34.2 34 33

Orlando (Percent)

Count

0 100 200 300 400 500

Click it or ticketBuckle up, seat belts save livesBuckle up, save livesDUI decide before you driveBuckle up, just do itSlow down & obey the posted speed limitNo excuses, buckle upReport impaired drivers, dial *347Drive safely, look twice for motorcyclesMove over for emergency vehicle, it’s the law

77.9 57.9 51.5 49

Count

0 100 200 300 400 500

Click it or ticketAlways wear your seat belt, it's the lawSeat belts save lives, buckle up
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Table 26. General opinions of PSAs on DMS. 

Philadelphia 

(n=497)

Orlando 

(n=500)

Chicago 

(n=584)

Houston 

(n=507)

“How often do you see PSAs on dynamic message signs while driving?”

Never 12 (2.4%) 14 (2.8%) 15 (2.9%) 8 (1.6%)

Rarely 70 (14.0%) 53 (10.7%) 2 (0.4%) 43 (8.5%)

Sometimes 224 (44.7%) 108 (21.7%) 248 (47.1%) 125 (24.8%)

Often 159 (31.7%) 120 (24.1%) 186 (35.4%) 186 (36.8%)

Always 36 (7.2%) 202 (40.6%) 75 (14.3%) 143 (28.3%)

“How useful is it to have PSAs on dynamic message signs for drivers?”

Never 23 (4.6%) 9 (1.8%) 12 (2.1%) 5 (1.0%)

Rarely 93 (18.6%) 46 (9.3%) 94 (16.2%) 63 (12.5%)

Sometimes 117 (23.4%) 111 (22.3%) 113 (19.5%) 104 (20.6%)

Often 173 (34.5%) 171 (34.4%) 173 (29.9%) 155 (30.8%)

Always 95 (19.0%) 160 (32.2%) 187 (32.3%) 177 (35.1%)

“Do you think PSAs on DMSs are more effective compared to other media?”

Never 17 (3.4%) 15 (3.1%) 7 (1.2%) 9 (1.8%)

Rarely 69 (13.8%) 67 (13.7%) 54 (9.4%) 49 (9.7%)

Sometimes 167 (33.5%) 145 (29.6%) 183 (31.8%) 179 (35.4%)

Often 187 (37.5%) 141 (28.8%) 247 (43%) 175 (34.7%)

Always 59 (11.8%) 122 (24.9%) 84 (14.6%) 93 (18.4%)

Most responses in all cities were in the “sometimes” and “often” category for all three of these 

questions, indicating a somewhat positive opinion on using PSAs on DMS. 

These questions are not specific to capturing recognition of the message itself. For example, the 

first question listed in Table 26 is “How often do you see PSAs on dynamic message signs while 

driving?” Approximately 84 percent of respondents selected “sometimes,” “often,” or “always”

in Philadelphia. Although, only 39 percent reported “often” and “always,” again the question was 

not targeted toward recognition, but how often the respondents see these messages specifically

on DMS while driving. Also, respondents may view similar messages on other media such as 

billboards or TV, and it may not be as easy for individuals to recall whether the message was 

from DMS or another media form. 
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All four cities were also surveyed on their opinions of reinforcement messages on the DMS. 

These questions ranged from posting consequences (e.g., “Drink, drive, go to jail”) to including 

crash statistics (e.g., “100 deaths this year on Texas road”) to showing a specific fine (e.g., 

“Click it or ticket or get $100 fine”). The results for these questions can be viewed in Figure 13

(a) (b) (c) and (d). In all cities, participants agreed that they were neutral about to somewhat 

comfortable with reading consequences; somewhat agreeing that PSAs with crash statistics are 

more effective and their driving would be strongly impacted by signs that showed a fine. 
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Figure 13 (a) (b) (c) (d). Chart. “How much do you agree or disagree with the following 

statements...”

Furthermore, each city was asked the same set of questions with regards to the importance of 

providing information to drivers on six common safety issues—motorcycle awareness, driving 

impaired, work zone safety, distracted driving, speeding, and seatbelt usage. These results are 

portrayed in Figure 14 (a) (b) (c) and (d). On average, people thought it was very important to 

provide information to drivers on all six of these concerns, with less emphasis on staying below 

the posted speed limit. 
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Figure 14 (a) (b) (c) (d). Chart. “How important is it to provide information to drivers on 

the following...”

Similarly, actual messages displayed in each of these cities that correspond to the six safety 

issues were assessed for their impact on driver behavior. Survey respondents were asked “if they 

would change their driving behavior or habits if they saw the following PSA on DMS while 

driving?” The possible responses ranged from “definitely not” to “definitely yes.” Orlando had 

the strongest responses toward “definitely yes” on all messages. Chicago responded strongly 

with “definitely yes” for messages relating to slowing down for emergency vehicles and in 

construction zones, with a majority of mixed responses between “probably” and “definitely yes”

for the other messages. Philadelphia respondents were more neutral, with most responses in the 

“maybe” and “probably yes” behavior responses. Houston responses were the most scattered; the 
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only two messages with a strong majority correspond to the two messages with more assertive 

language (“100 deaths this year on Texas road” and “Drunk driving, over the limit, under 

arrest”). Figure 15 (a), (b), (c), and (d) further depict these responses in behavioral changes 

linked to specific PSAs. 
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Figure 15 (a) (b) (c) (d). Chart. “Would you change your driving behavior or habits when 

you see the following PSA on DMS while driving...”

INFERENTIAL STATISTICS

A chi-square test was conducted on the responses for opinions relating to posting consequences, 

crash statistics, and fines on PSAs to determine how the results differed based on city. All chisquare values were less than 0.05, indicating that PSA opinions significantly differ based on city.
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A binary logit model was developed for each city to predict the perceived usefulness of PSAs on 

DMS given various explanatory variables that include behavioral correlates and socioeconomic 

characteristics. The outcome was based on recoding the 5-point Likert scale so that those who 

indicated “Neutral” to “Less than useful” are coded 0 (not useful), and “Always useful” to 

“somewhat useful” are coded 1 (or useful). 

In all four cities, individuals were more likely to agree that PSAs on DMS were useful if they 

encountered them more frequently. If the user felt that posting PSAs on DMS would be highly 

effective, then they would also feel that PSAs were more useful. In Philadelphia, males 

considered PSAs more useful, while in Orlando, females considered PSAs more useful. Only in 

Chicago was income a factor, where lower income individuals were more likely to regard PSAs 

to be useful when compared to those with higher incomes. In three cities (Philadelphia, Chicago, 

and Houston), there was a higher likelihood of reporting that PSAs were useful if the surveyed 

subjects also considered conveying information on impaired driving to be important. Table 27

provides a more in-depth summary on this model. 

Table 27. Binary logit model for predicting perceived usefulness. 

Odds Ratio Confidence Interval

estimate p-value lower upper

Philadelphia

Frequency 1.56 0.002 1.18 2.01

Effective 2.84 <0.001 2.18 3.78

Seatbelt 2.11 0.017 1.15 3.92

DUI 1.99 0.042 1.03 3.90

Speeding - ns - -

Lives in Area - ns - -

Male 1.48 0.098 0.93 2.36

Younger - ns - -

Older - ns - -

High School - ns - -

Grad School - ns - -

Lower Income - ns - -

Crash - ns - -

Tickets - ns - -

Null Deviance = 575.64

Residual Deviance = 458.13
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Odds Ratio Confidence Interval

estimate p-value lower upper

Orlando

Frequency 1.68 <0.001 1.31 2.17

Effective 1.94 <0.001 1.48 2.58

Seatbelt - ns - -

DUI - ns - -

Speeding 2.56 <0.001 1.48 4.41

Lives in Area - ns - -

Male* 0.60* 0.046* 0.36 0.99

Younger - ns - -

Older - ns - -

High School - ns - -

Grad School - ns - -

Lower Income - ns - -

Crash - ns - -

Tickets* 0.47* 0.028* 0.24 0.92

Null Deviance = 485.44

Residual Deviance = 369.04

* Odds ratio estimate is less than 1. 

Odds Ratio Confidence Interval

estimate p-value lower upper

Chicago

Frequency 1.46 0.007 1.11 1.94

Effective 3.50 <0.001 2.57 4.87

Seatbelt - ns - -

DUI 4.00 <0.001 1.93 8.52

Speeding 1.84 0.013 1.14 2.97

Lives in Area* 0.65* 0.086* 0.40 1.06

Male - ns - -

Younger* 0.67* 0.111* 0.41 1.10

Older* 0.48* 0.074* 0.22 1.08

High School - ns - -

Grad School - ns - -

Lower Income 2.16 0.014 1.18 4.08

Crash* 0.61* 0.079* 0.35 1.06

Tickets - ns - -

Null Deviance = 573.19

Residual Deviance = 439.46

* Odds ratio estimate is less than 1. 
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Odds Ratio Confidence Interval

estimate p-value lower upper

Houston

Frequency 1.60 <0.001 1.24 2.08

Effective 2.11 <0.001 1.61 2.81

Seatbelt - ns - -

DUI 2.54 0.014 1.21 5.39

Speeding 1.73 0.028 1.06 2.84

Lives in Area - ns - -

Male - ns - -

Younger* 0.53* 0.019* 0.31 0.90

Older - ns - -

High School* 0.62* 0.080* 0.36 1.06

Grad School* 0.41* 0.019* 0.19 0.87

Lower Income - ns - -

Crash - ns - -

Tickets - ns - -

Null Deviance = 495.67

Residual Deviance = 414.44

* Odds ratio estimate is less than 1. 

Notes: 

– Frequency = encounter PSAs always or sometimes 

– Effective = consider PSAs on DMS more effective/much more effective compared to other media means

– Seatbelt/DUI/Speeding = consider important/very important to provide information on topic to drivers

– Younger = less than 30 years old

– Note 5: Older = older than 60 years old

– Note 6: High School = some high school or high school diploma

– Note 7: Grad School = some graduate school or postgraduate degree

– Note 8: Lower Income = less than $25,000 per year

– Note 9: Crash/Tickets = has been in at least one crash/received ticket within past 5 years

A second binary logit model was developed to predict the perceived effectiveness of PSAs on 

DMS given variables that were identical across all four cities. Rather than four separate models 

for each city, this model is aggregated across all survey locations. Similar to the first model, 

survey questions based on the 5-point Likert scale were recoded such that “Neutral” to “Less 

than effective” are coded as 0 (for not effective), and “Always effective” to “somewhat 

effective” are coded as 1 (or effective). 

Table 28 provides the model summary for the aggregated data across all cities. Individuals were 

1.74 times more likely to consider PSAs effective on DMS when they encountered PSAs 

frequently and were 3.29 times more likely if they also consider PSAs to be useful. These 

outcomes echo the findings at the individual city level. In addition, individuals who had some 
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graduate schooling or a postgraduate degree were 1.34 times more likely to find these 

messages effective. 

Based on the aggregation across all cities, the team was also able to examine interaction effects. 

Specifically, lower income males were less likely to find these DMS effective. Older respondents 

(older than 60) were more likely to consider PSAs effective, while younger respondents (less than 

30) were less likely to consider them effective. As a reference, 10 percent of the dataset included 

lower-income males, 8 percent were in the older category, 57 percent were younger, and 17 percent 

were represented by the graduate school variable. 

Table 28. Binary logit model for predicting perceived effectiveness when compared to other 

edia. m

Odds Ratio Confidence 

Interval

estimate p-value lower upper

Frequency 1.74 <0.001 1.41 2.15

Useful 3.29 <0.001 2.64 4.10

Low Income Male* 0.73* 0.081* 0.52 1.04

Younger* 0.76* 0.017* 0.60 0.95

Older 1.55 0.051 1.00 2.42

Grad School 1.34 0.048 1.00 1.79

Null Deviance = 2249.5

Residual Deviance = 2039.6

Observations = 1620

* Odds ratio estimate is less than 1. 

Notes: 

– Frequency = encounter PSAs always or sometimes 

– Useful = consider PSAs on DMS useful or very useful 

– Low Income Male = males with an annual income less than $25,000 

– Younger = less than 30 years old 

– Older = older than 60 years old

– Grad School = some graduate school or postgraduate degree
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CHAPTER 6. FINDINGS AND RECOMMENDATIONS/GUIDANCE 

Summary data showed that respondents do take assertive PSAs quite seriously (e.g., monetary 

fine and number of deaths). In Philadelphia, respondents appeared to be more uncomfortable 

with messages that include direct consequences (e.g., drink and you will go to jail), when 

compared to Chicago and Houston. This could be due to the fact that those that drive in Chicago 

and Houston are more accustomed to seeing these message displays as compared to Philadelphia. 

Respondents in all four cities indicated that PSAs that show a monetary fine would impact their 

driving, as would data displayed on number of crashes. 

There were two inferential models developed. Table 29 summarizes the findings from the four 

models developed to assess the usefulness of PSAs on DMS; an up arrow corresponds to 

“perceived as more useful,” a down arrow corresponds to “perceived as less useful,” and ‘ns’

corresponds to “not a significant variable within that location.” Four models were developed to 

observe the differences within each city. All factors in Philadelphia had an increasing effect on 

perceived usefulness; however, this was not observed in any other city. It is important to note 

that encountering PSAs often and considering PSAs effective increased perceived usefulness at 

all locations. In addition, two locations observed respondents younger than 30 year old to 

consider PSAs not useful. 
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Table 29. Perceived usefulness of PSAs on DMS summary. 

Perceived Usefulness

Location

Philadelphia Orlando Chicago Houston

Encounters PSAs often    

PSAs on DMS are effective    

PSAs on seatbelts are important  ns ns ns

PSAs on DUI are important  ns  

PSAs on speeding are important ns   

Lives within greater area ns ns  ns

Male   ns ns

Younger than 30 years old ns ns  

Older than 60 years old ns ns  ns

Some high school or high school diploma ns ns ns 

Some graduate school or postgraduate degree ns ns ns 

Income less than $25,000 per year ns ns  ns

Has been in at least 1 crash within 5 years ns ns  ns

Has received at least 1 ticket within 5 years ns  ns ns

Another model was designed to examine the effectiveness of PSAs when compared to other media 

types (e.g., radio, billboard, TV), and this model was based on data pooled from all four cities. In 

this latter model, a smaller subset of data was used. More specifically, this model captured only 

data that was identical in all four cities. This summary is provided in Table 30, where up arrows 

indicate factors that increased perceived effectiveness and down arrows represent factors that 

decrease perceived effectiveness. Insignificant variables are not included in this summary. 

Table 30. Perceived effectiveness of PSAs on DMS summary. 

Perceived Effectiveness Effect

Encounters PSAs often 

PSAs on DMS are useful 

Male with income less than $25,000 per year 

Younger than 30 years old 

Older than 60 years old 

Some graduate school or postgraduate degree 
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Respondents were provided with specific PSAs commonly displayed on DMS in their city and 

asked whether they would change their driving behaviors when they saw those messages. 

 In Orlando, the largest proportion of responses stipulated that drivers would definitely 

change their driving behaviors when they saw all nine example messages. 

 In Chicago, the majority of responses were that all eight messages would probably or 

definitely change their driving behaviors. The messages with the largest impact on driving 

were about slowing down for work zones and emergency vehicles. 

 The eight example messages in Philadelphia had the largest number of responses in the 

“maybe” to “probably” changing driving behaviors. 

 Houston respondents reported the least amount of consistency in behavioral changes from 

their nine example messages. The only two messages with a majority response were “Drunk 

driving, over the limit, under arrest” and “100 deaths this year on Texas road,” based upon 

which drivers would definitely change their behaviors. It is to be noted that these were the 

only two messages with assertive language. 

The assumption is that most survey respondents spoke English and had an 8th grade education 

level. Considering the population of survey respondents, this assumption appears to hold true as 

the majority did indicate English as their primary language, and the majority did indicate that 

they had some high school education or higher. Hence, many of the words used in the survey 

were not defined (e.g., distraction, safety, consequence). Based on earlier meetings with the state 

transportation agencies, it was deemed important to separate usefulness from effectiveness. 

Although the survey did not define usefulness or effectiveness to the survey respondents, the 

goal was to consider usefulness as a practical and functional application of PSAs on DMS. 

Effectiveness captured the perception that DMS were the most successful medium to deliver 

PSAs in a way that would impact driver behavior. 

In general, most respondents across the four cities indicated that PSAs on DMS appear useful. 

Respondents with an income lower than $25,000 annually did not find these messages to be 

useful, but this effect was observed in Houston only. Respondents who have been in a crash or 

had received a ticket in the past 5 years were less likely to find PSAs to be useful. 

When aggregated across all four cities, producing a larger sample size, young males with lower 

incomes tend not to find these messages effective. Older drivers and drivers with a higher 

education found safety and PSA messages on DMS to be effective, while younger drivers did not. 

Traditionally, DMS are used to provide useful travel information to drivers so that they know 

whether they need to change routes, reduce speed, or change lanes. This study showed that there 

could be some possibility of changing driver behavior if safety and PSA messages were also 

posted on DMS. For example, those drivers who reported that certain safety issues are important 

to disseminate (e.g., driving under the influence or staying below the speed limits) also found 

PSAs to be both useful and effective. However, it would be very important to ensure that PSAs 
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that are placed on DMS are both useful and effective. Hence, more testing and studies would be 

needed to validate whether the perceptions noted in the surveys translate to real-world driving. 

Often, drivers’ stated preferences differ from their revealed preferences. Another concern that 

should be tested on-road is whether the inclusion of additional PSAs would be more distracting 

to travelers, impacting their overall safety. Lastly, there is a cost associated with operating DMS 

in terms of maintenance and use. Again, these issues would need to be examined in the real 

world. Table 31 provides some overall recommendations based on the study’s key findings.

Table 31. PSAs on DMS – recommendations and guidance. 

Findings Recommendations/Guidance

Assertive PSAs (e.g., monetary fine 

and number of deaths) are taken 

seriously

Assertive PSAs need to be examined more carefully to 

identify the impact on driver behavior.

PSAs that show a monetary fine 

impact driving

It is uncertain whether including monetary fines has a 

good or bad impact on driving. Hence, PSAs that show

monetary fines need to be examined on-road.

PSAs that include data on crash 

statistics impact driving

It is uncertain whether including crash statistics will 

have a good or bad impact on driving. Hence, PSAs that 

show crash statistics need to be examined on-road 

before further implementation.

There is an association between the 

frequency of observation of PSAs on 

DMS and the perceived usefulness

More studies need to be done to pinpoint the appropriate 

number and frequency of PSAs on DMS to avoid the 

introduction of an unnecessary number of messages.

Younger respondents (less than 30) 

are less likely to consider PSAs on 

DMS effective

Promote awareness on (and familiarity with) PSAs 

among the younger groups of population.
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APPENDIX A: SURVEY QUESTIONNAIRES 

CHICAGO 
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HOUSTON 
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ORLANDO 
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PHILADELPHIA 
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APPENDIX B: SAMPLE SIZE CALCULATION 

Observational studies such as the one in this task order differ from controlled studies, and any 

statistical models developed need to include potential covariates and interaction effects. The 

greater the number of covariates, the greater the sample size needed to ensure sufficient power to 

minimize Type II errors. There is a need to be sufficiently confident that any insignificant 

findings observed are not due to large variations in too small a sample and that any impacts from 

outliers are minimized. 

In the absence of subject compensation, and based on past studies, a 25- to 30-percent survey 

response rate is anticipated. 

Simple random sampling is used to compute the needed sample size. The necessary sample size 

is calculated such that: 

Pr[| p-P |> d]= 0.05 Equation 1

Where: 

 p is the estimated proportion of people who will engage in a certain behavior (for example, 

wear seat belt) 

 P is the true proportion of people in the target population that will engage in a certain 

behavior 

 d is the margin of error -- it specifies the desired level of precision in the sample estimate, p, 

to be with respect to P. 

Equation 1 above states that the sample size is calculated such that there is only 5-percent 

chance (or with a 95-percent confidence level) that the sample estimate p will deviate from the 

true population parameter P by more than d. Derived from equation 1, the formula to calculate 

the number of survey responses needed n becomes: 

 

 ( )

 

 Equation 2

Where: 

 z is equal to 1.96 at a 95-percent confidence level 

To calculate n, both p and d need to be specified and n varies as p and d change. The larger the 

sample size, the smaller is the margin of error. P (See Table 32 for examples) will be estimated 

from the pilot survey (it can also be obtained from the existing literature, i.e., based on 

experience). 
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Table 32. Needed number of responses n as a function of P and d.

d\P 0.1 0.2 0.3 0.4 0.5

0.05 71 125 165 188 384

0.075 31 56 73 84 87

0.1 18 31 41 47 49

0.15 8 14 18 21 22

n refers to the number of responses. Thus, assuming a 10-percent response rate, the final sample 

size needed should be 10*n. 

If the sample estimate p is 0.5 and the margin of error is d is 0.05, then a sample size of N=384 

is reasonable. 

It is important to note that this is the number of surveys that need to be returned and not the 

number distributed, which will need to be much higher. The response rates for each survey 

conducted in past studies have varied (from 10 percent to 35 percent), which creates sampling 

biases that also need to be accounted for statistically. 

Given these estimates, 500 surveys need to be returned per site. Thus, with four sites, 2000 total 

surveys should be sufficient to achieve a 95-percent confidence interval. 
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APPENDIX C: POTENTIAL SURVEY LOCATIONS BY CITY 

Table 33. Potential survey locations—Houston, TX. 

Location Address Type of 

Facility

Major Access

Roads

App.# 

Parking 

Spaces

# of 

DMS

within 2-

Mile 

Radius 

(Approx)

ADT

Northwest 

Transit 

Center

7373 Old Katy Rd.

Houston, TX 

77024

Park-n-Ride

for Houston 

Metro Bus

At interchange 

of I-10 (Katy 

Fwy) and 

Route 610 (W. 

Loop Fwy)

180 5

Eastex 

Park-nRide

14400 Old Humble 

Rd.

Houston, TX 

77396

Park-n-Ride

for Houston 

Metro Bus

Near 

Interchange of 

Route 69 

(Eastex Fwy) 

and Route 8 

(North Sam 

Houston 

Pkwy)

1000 2

Fannin 

South

Park-nRide

1604 West Bellfort

Houston, TX 

77054

Park-n-Ride

for Houston

Metro Bus 

and Metro 

Rail 

Off of Route 

610 (S. Loop 

Fwy)

1500 4

Fuqua 

Park-nRide

11755 Sabo Rd.

Houston, TX 

77089

Park-n-Ride

for Houston 

Metro Bus

Off of Route 

45 (Gulf Fwy) 700 2

Gulfgate 

Transit 

Center

7400 South Loop 

East

Houston, TX 

77087

Park-n-Ride

for Houston 

Metro Bus

At interchange 

of Off of Route 

610 (S. Loop 

Fwy) and 

Route 45 (Gulf 

Fwy)

200 4
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Table 34. Potential survey locations—Chicago, IL. 

Location Address Type of 

Facility

Major

Access

Roads

App.# 

Parking 

Spaces

# of 

DMS

within 2-

Mile 

Radius 

(Approx)

ADT

Cumberland 

Park-n-Ride

5800 N. 

Cumberland 

Ave., 

Chicago, IL 

60631

Park-n-Ride

Lot for “L” 

Train Blue 

Line Train 

and CTA 

Buses

Off of Route 

90 (Kennedy 

Expy)

1600

(Parking 

garage)

1

Route 

90: 

200,000

LaSalle St 

Station 

(Chicago 

Stock 

Exchange)

121 W. Van 

Buren St., 

Chicago, IL 

60605

Parking Lots 

for Several 

“L” Train 

Lines (Brown, 

Orange, Pink, 

and Purple 

Lines) 

Off of Route 

290 (Dwight 

D. 

Eisenhower 

Expy) in 

downtown 

170 2

Route 

290: 

228,000

Garfield Red 

Line Station

220 W. 

Garfield Blvd., 

Chicago, IL 

60609

Parking Lot 

for “L” Train 

Red Line and 

CTA Buses

Off of I-90 

(Dan Ryan 

Expy)

350 1

Not 

Avail.

Shell / BP 

Gas Station 

Intersection of 

W Touhy Ave.

and N. Cicero 

Ave.

Gas Station

Off of Route 

94 (Eden 

Expy)

N/A 2

Route 

94: 

164,000

Target 

Shopping 

Center

Intersection of 

Harrison St.

and S.

Manheim Rd.

Shopping 

Center

Off of Route 

290 (Dwight 

D. 

Eisenhower 

Expy) 

1000 1

Route 

290: 

189,000
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Table 35. Potential survey locations—Orlando, FL. 

Location Address Type of 

Facility

Major Access

Roads

App.# 

Parking 

Spaces

# of 

DMS

within 2-

Mile 

Radius 

(Approx)

ADT

Turkey Lake 

Service Plaza

Mile Post 

263

Florida 

Turnpike

Highway 

Rest Stop

Florida 

Turnpike

350 plus 

truck 

parking

2 71,000

Orange County 

Convention 

Center

9400 

Universal 

Blvd.

Orlando, 

FL 32819

Convention 

Center –

would focus 

on 

intercepting 

in parking 

lots

At 

interchange of 

Route 528 

(Martin 

Anderson Bee 

Line Expy) 

and I-4

2000 3

Route 

528: 

77,800

I-4: 

132,000

Orlando Amtrak 

Station

1400 Sligh 

Blvd.

Orlando, 

FL 32806

Train 

Station

Near 

interchange of 

I-4 and Route 

408 (Spessard 

Holland EastWest Expy)

80 5

I-4: 

132,000

Route 

408: 

64,000

Econlockhatchee 

Park-n-Ride

9555 East 

Colonial 

Dr.

Orlando, 

FL 32817

Park-n-Ride

Lot

Off of Route 

417 (Eastern 

Beltway)

41 2

Route 

417: 

57,000
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Table 36. Potential survey locations -- Philadelphia, PA. 

Location Address Type of 

Facility

Major

Access

Roads

App.# 

Parking 

Spaces

# of 

DMS

within 2-

Mile 

Radius 

(Approx)

ADT

I-95 PA 

Welcome 

Center

1⁄2 mile from 

PA/DE Border 

on I-95

Highway Rest 

Stop I-95 NB

80 plus 

truck 

parking

1

I-95: 

80,000 

(NB 

only)

30th St 

Station

93 N. 30th St. 

and Market St.

Philadelphia 

PA 19104

Parking Lot 

for Multiple 

Regional Rail 

Lines, 

Amtrak, NJ 

Transit Bus 

Routes

Off of 

Route 76 

(Schuykill 

Expy)

1,000

(incl. 

surface 

lots and 

parking 

garage)

Route 

76: 

72,000

Penn’s 

Landing 

Parking Lot

Intersection of 

Columbus 

Blvd. at South 

St.

Parking Lot 

for SEPTA 

Bus Routes 

and Tourists 

to Penn’s 

Landing

I-95 240 I-95: 

80,000

Wissahocken 

SEPTA 

Station

5099 Ridge 

Ave. and

Osborn St.

Philadelphia, 

PA 19128

Parking Lot 

for SEPTA 

Station

Off of Route 

76 

(Schuykill 

Expy)

206

Route 

76: 

68,000
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ACKNOWLEDGEMENTS 

We would like to acknowledge the following TMC PFS members for their contributions, 

support, and technical guidance during this project: 

 Brian Kary – Minnesota DOT. 

 Ed Sirgany – North Carolina DOT. 

 Davis Behzadpour – Kansas DOT. 

 John Bassett – New York DOT. 

 Vinh Dang – Washington State DOT. 

 Leslie McCoy – Pennsylvania DOT. 
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