Harnessing Social Media to Reduce Cannabis Use Among Adolescents and Emerging Adults in an Urban Emergency Department
Phase: NA
Conditions: Cannabis Use
Sponsor: University of Michigan

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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Study Protocol 
Currently Approved Protocol: 11/8/2022 
 
 
 
 
IRBMED #: HUM00139068 
 
Study Title: SnapCoach 
 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
Principal Investigator: Erin E. Bonar, PhD 
 
Co-Investigators:  
Maureen A. Walton, MPH, PhD 
                                 Patrick M. Carter, MD 
                                    Jason E. Goldstick, PhD 
 
NCT: NCT04316741  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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Background 
 
     In the United States, cannabis use peaks during emerging adulthood (ages 18-25)1 and there 
is a national trend of increasing cannabis use among emerging adults (EAs).2 Monitoring the 
Future (MTF) data show daily use increased from 2007 to 2014-- from 3.5% to 5.9%-- in both 
college and non-college EAs.3 These rates coincide with shifting cannabis attitudes,4 including 
decreasing risk perceptions,5 and the belief among youth that cannabis is easy to obtain.3 EAs 
living in urban, low socioeconomic areas comprise a population in need of focus due to their 
higher rates of cannabis use and cannabis use disorders.2  In addition, interventions initiated at 
healthcare visits, where youth tend to have higher rates of risky behavior, could have higher 
impact than if the intervention was given in a different location (i.e. college campus). 
     Cannabis use is associated with health risks and negative consequences among EAs. Early 
use of cannabis increases risk for substance use disorders and other problems into adulthood, 
including increased mortality.6 Cannabis use is related to higher risk for both short and long term 
negative physical, psychiatric, and social outcomes.7 In addition, cannabis use may affect 
neuro-maturational development processes, causing adverse emotional and cognitive changes, 
8, 9, 10 and it can compromise decision making and inhibitory control. 10,11,12 Escalating use is 
attributed to social ecological factors such as individual level factors (i.e. mental health, 
delinquency, sex), and social/environmental influences (i.e. peers, norms, parents, 
community).13,14,15 However, acute use of cannabis also has alarming effects. Acute use alters 
executive function (i.e. attention, decision making, inhibition, impulsivity, risk taking, memory, 
concentration)9,16 and increases propensity for risky behaviors (i.e. risky sex 17,18, impaired 
driving 19,20). Reducing cannabis use is critical due to the high usage and potential negative 
impact of cannabis use for EAs, especially those in urban, underserved settings with disparities 
in access to services. 
The conceptual framework (Fig. 1) guiding our 
intervention incorporates theories of initiation and escalation of 
cannabis use and behavior change, including, motivational, 
behavioral, social cognitive, social-ecological, and SM influence 
theories. We implicitly incorporate the trans-theoretical 
model,79,80 strengths and resiliency-based approaches,81,82 and 
principles of harm reduction,83 with our intervention focus on 
eliciting alternatives to address motives for use in SnapCoach.  
     Given the role of peer influences in EAs’ drug use,21 
harnessing peers for intervention delivery is a potentially viable 
strategy. Social media (SM) is an intervention platform which 
can extend healthcare interventions to EAs’ individual, social, 
and environmental context especially because SM has 
infiltrated EAs’ daily lives.22 A pervasive form of SM for EAs is 
Snapchat 23,24,25-- which is why we propose to harness this 
platform for intervention delivery to potentiate reach, 
engagement, and efficacy. 
      
 
 
 
 
For these reasons, we seek to develop and test a social 
media based intervention for cannabis use among EAs, 
delivered by health coaches who will be similar age or slightly 
Figure 1. Guiding Framework for 
Intervention. 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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older peers (i.e. clinical practicum students, bachelor’s level psychology students, master’s level 
public health and social work students). The guiding framework for this intervention can be 
found in Figure 1. 
  
Objective 
 
The specific aims of this clinical trial is to: 
 
Conduct a randomized clinical trial of the SnapCoach intervention, where we will examine 
feasibility and acceptability of the SnapCoach Intervention as our primary outcome measures. 
As exploratory, other outcomes we will examine the preliminary efficacy of SnapCoach (vs. 
usual care control with attention-placebo; N=approximately 50 per group) on cannabis use 
(quantity, frequency) and consequences.  
We will conduct a randomized clinical trial (RCT), to examine the feasibility, 
acceptability, and initial efficacy of the SnapCoach intervention. Our goal is to recruit N = 100 
participants (as our target N) meeting eligibility criteria, who will complete baseline measures, 
and be randomized to receive the SnapCoach intervention or a control condition. They will 
participate in the 4-week intervention/control condition, with a post-test administered at 1-month 
post-baseline (i.e., end of 4-week intervention period) and a follow-up assessment of outcomes 
at 3-months post-baseline. 
Primary outcomes are feasibility and acceptability of the Snapcoach intervention. Other 
exploratory outcomes include measures of cannabis quantity and frequency and consequences 
measured at the 3-month follow-up, examining the effect of the intervention on other substance 
use (alcohol, other drugs), analyses of moderators and mediators (e.g., sex, cannabis use 
motives), identification of the most engaging intervention content, dose-response analyses, and 
measurement of intervention delivery costs. 
 
Aim 2 Methods: 
Enrollment 
     Target enrollment is 100 emerging adults (approximately 50% males and 50% females) 
between the ages of 18-25, in a 2-arm pilot RCT of SnapCoach compared to an enhanced usual 
care (EUC) with attention placebo for EAs with weekly cannabis use.  
 
Recruitment Procedures 
Participants will be recruited either during or post-emergency department (ED; including 
urgent care) visit at Hurley Medical Center (HMC) which is a public, academic, Level-1 Trauma 
Center located in Flint, Michigan. Enrollment will focus on recruiting approximately 50% males 
and 50% females. Potential participants will be screened for eligibility using a 5-10 minute 
screening survey.  Randomization to conditions will be balanced based on sex (male, female), age 
(ages 18-20, ages 21-25), and more than once a day cannabis use, using urn randomization in 
blocks of 4.  
Modifications to recruitment procedures for the purposes of remote recruitment are 
described here: 
For remote recruitment, RAs will contact ED patients ages 18-25 who meet 
screening inclusion criteria (listed below in “Study Eligibility Criteria”) within 60 days of 
discharge to invite them to consent and complete a web-based screening survey.  RAs 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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will determine who to contact by viewing HMC’s ED medical records (same records 
viewed as during in-person recruitment), they may send a text message to let the 
participant know we will be contacting them.  Using contact information obtained from 
the medical record, RAs will follow a phone recruitment script for these procedures, 
obtain verbal informed consent prior to starting the screening survey and document RA 
name and date consent is obtained.   
After consenting, interested participants may choose to self-administer the 
survey online or complete an RA-administered version over the phone.  For verbally 
consented participants completing the survey online, a copy of the screening consent 
form will appear at the beginning of the survey.  Other participants may prefer to interact 
with us via text message, in this case we may adapt the phone script for text messaging, 
and we will obtain electronic consent at the beginning of the screening survey.  
Participants recruited remotely will not receive a token gift for completing the screening 
survey. 
Those meeting eligibility criteria (see below) on the screening survey will be 
eligible for enrolling in the trial and completing the baseline procedures. RAs will explain 
the study to participants during the baseline consenting process. Interested participants 
will be enrolled in the study after completing verbal consent over the phone and RAs will 
document their name and date consent is obtained.  A copy of this consent form will also 
be shown online at the beginning of the baseline survey. 
 
Briefly, because participants will be identified via reviewing the ED medical chart we are 
requesting an update to our waiver of HIPAA authorization to accommodate remote 
recruitment. We are also requesting an update to our waiver of documentation to 
accommodate remote recruitment.  At screening, consistent with prior procedures, interested 
participants will be asked to complete an electronic informed consent or verbally consent to 
complete the screening assessment.  In addition, this waiver will apply to remote completion of 
baseline procedures allowing for verbal consent obtained over phone.  
      
Study Eligibility Criteria 
Screening inclusion criteria: (1) Emerging adults (ages 18-25) presenting to the Emergency 
Department (including Urgent Care) on the day of in-person recruitment; presenting within 60 
days of contact for remote recruitment and (2) owning a working smartphone. Additional 
baseline inclusion criteria: (3) weekly or more frequent non-medical cannabis use for the past 3 
months; and (4) any Snapchat use in the past month. Exclusion criteria: (1) Does not 
understand English; (2) presenting to the ED for sexual assault or acute suicidality; (3) unable to 
provide informed consent due to medical/psychiatric reasons/having a legal guardian; (4) Aim 1 
participant.    
 
Study Procedures 
After enrolling in the study, EAs will complete a 15-20 minute baseline survey, a 15-30 minute 
RA administered semi-structured Timeline Follow-Back calendar (TLFB), and a urine drug 
screen (UDS) (for in-person recruitment), before they are randomized to condition (SnapCoach 
or EUC). They will also complete a 3-minute immediate post-test and provide contact 
information.  For these activities participants will receive $40. When a participant is recruited 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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remotely, they will not complete the UDS during the baseline procedures. For these remote 
participants, and when an in-person participant does not complete the UDS during baseline 
procedures for any other reason, those participants will still be compensated a total of $40.  Our 
consents do not reflect that a participant will still receive $40 if they do not complete the UDS 
because doing so could adversely affect UDS completion rates among participants who would 
otherwise be willing to complete the test.  Participants will also complete their assigned 
condition (i.e., SnapCoach initial session or EUC: review of health and community resources, 
with the same information contained in a paper brochure or electronic format depending on type 
or recruitment). Enrolled participants may also receive small items such as candy, water bottles, 
notebooks, etc., or small tchotchkes with project logo and phone number (e.g., lanyard or pen) 
during the study. These tokens are not used as a contingency of study participation. 
For those assigned to the intervention condition, the SnapCoach initial session is an 
intervention delivered in the ED and/or remotely (e.g., facetime, bluejeans, vidyo, or Skype for 
Business) by research health coaches using a computer. The health coaches will use a 
computerized guide and Motivational Interviewing (MI) to engage EAs and understand their 
cannabis use. Sessions will be followed by reviewing a health and community resources that the 
participants keep (provided electronically or on paper, dependent on type of recruitment). This 
session will take about 30-45 minutes and will be audio-recorded.  
 
Participants will receive pre-selected snaps, up to 3 per day, from health coaches over 4 
weeks. The final Snapchat content was created based on focus testing participant ratings and 
feedback and/or engagement data, and uses the Why/How model of MI. Messages address 1) 
Why (evoking reasons for change), and/or 2) How (Tools for change). We also send 
encouraging greetings/affirmations to enhance engagement.  
For those assigned to the control condition, they will receive a brochure and review 
health and community resources that the participants keep (provided electronically or on paper, 
dependent on type of recruitment), exceeding current standard of care for drug using EAs at 
HMC.  As an attention-placebo, participants will add coaches on Snapchat, and receive 
messages that do not contain intervention content (e.g., entertainment, trending content such as 
memes or gifs, weather, current events]). Coaches will thank participants for any responses via 
2-way messaging, but will not engage in MI. 
As additional enrollment activities, all participants will watch brief introduction videos of 
the health coaches, who they will be communicating with on Snapchat, welcoming them to the 
project and introducing themselves. Participants will also “add” the coaches on Snapchat via 
their mobile phones and the RA will send a snap to confirm the connection. Snapchat involves 
2-way messaging; when participants in the intervention condition reply to messages, coaches 
will discuss content, in a MI-consistent manner91 using reflections, open questions, and 
affirmations to participants during designated shift times. Participants who are unable to 
complete the baseline procedures and intervention while in the ER may be able to complete 
those activities within 72 hours by returning to the study site or remotely using telephone/video 
conference and web-based surveys. Likewise, participants who join remotely will have up to 30 
days after providing consent to complete baseline procedures. Coaches will use an electronic 
log to track ingoing/outgoing messages and metrics such as whether messages were viewed by 
the recipient and types of content discussed to quantify engagement. Coaches will monitor 
Snapchat to determine if messages were viewed and send periodic reminders (e.g., via SMS) to 

 
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prompt engagement when messages go unopened; these reminder messages will also be 
recorded on a log.   
There will be two follow-up assessments, at 1-month and 3-months post-baseline 
assessment. After the 4 weeks of interacting with health coaches on Snapchat, participants will 
be completing a 20-minute online, video, phone or in-person (depending on participant 
preference) 1-month follow-up assessment ($25), and an in-person, online, video or phone 
(depending on participant preference) 3-month follow-up assessment which includes a web-
based survey, the RA-administered TLFB, and a UDS (if in-person) to encourage accuracy of 
substance use reporting. Participants will receive $40 for the 3-month assessment. When a 
participant is recruited remotely, they will not complete the UDS for the 3-month assessment.  
For these remote participants, and when an in-person participant does not complete the UDS at 
the 3-month assessment for any other reason, those participants will still be compensated a 
total of $40.  Follow-up assessment reminders will be sent in a variety of ways which may 
include via e-mail, private Snapchat messaging, SMS text message, mail and/or phone call and 
other social media, based on contact information participants provide at the enrollment 
assessment.  Three-month follow-up assessments completed in-person may be done at the 
HMC, or other community locations for participant convenience. During the RA-administered 
TLFB, the participants will view pictures and response cards either on paper (when in person) or 
given the option to view them electronically when completed over the phone (sent to the 
participant via preferred method, e.g., email, text, or in a shared online document, etc.).  The 
RA-administered TLFB and intervention sessions will be audio-recorded. Whenever possible, 
follow-up staff completing assessments will be blinded to condition assignment. 
 
Measures 
     We will use reliable, valid measures from prior work with EAs, reflecting our conceptual 
model: demographics; SM involvement; cannabis use, motives, and consequences; and 
protective strategies, etc. (Table 1). Some measures (e.g., intervention ratings) were created for 
use in this study. 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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Table 1. Measures.  
(S=Screening, B=Baseline, I=Immediate Post-test, 1M=1-month follow-up, 3M=3-month 
follow-up  
Individual Level and Descriptive Characteristics 
Demographics: Age, Sex, Race, Ethnicity (adapted from national 
surveys, e.g., the Youth Risk Behavior Survey 39)  
S 
Demographics: Gender identity, Sexual Orientation, School Status, 
Employment, Living Situation, Children, Marital Status, Pregnancy 
(adapted from national surveys, e.g., the Youth Risk Behavior Survey 39) 
B,3M 
Demographic: Parents and Personal Income 86,87  
B 
Service Utilization: ER and Urgent Care 86,87 
B,3M 
1-minute delay discounting task 84 
S,1M,3M 
Snapchat involvement (modified) 22,40,41,42 
S 
Comprehensive Marijuana Motives (modified) 43  
B,3M 
Perceived risk of cannabis (modified for different cannabis modalities) 44 
S,1M,3M 
Importance, Self-Efficacy, Intention Rulers 45,46 
B,I,1M,3M 
Cannabis acquisition, strain, and medical marijuana,47,48,49,50,51,74 
                                               Cannabis acquisition  
                                               Preferred Marijuana Strain 
                              Medical Marijuana 
  
B,1M,3M 
B 
S,3M 
NIDA modified ASSIST 65,66,85 
S,3M 
Alcohol use frequency (AUDIT-C) 73 
S,3M 
Tobacco and Nicotine use (modified) 65 
S,1M,3M 
Mental health: Patient Health Questionnaire-2; Generalized Anxiety 
Disorder-2 52,53,54,55,56,57,58,59,60,61 
B,1M,3M 
Protective Behavioral Strategies for Marijuana (modified) 77 
B,3M 
Gun Carriage 75,76 
B 
Hope 78 
B,1M,3M 
Peer/Social Influences 
Cannabis online norms and exposure 64,41 
B,1M,3M 
Exploratory Outcomes 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
emerging adults in an urban emergency department 
 
 
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Data Management and Analysis 
 
Randomized participants will be included in intent-to-treat analyses, regardless of group 
engagement. By design, groups will be balanced based on sex, age, and more than once a day 
cannabis use, using urn randomization in blocks of 4; we will validate randomization by 
evaluating covariate balance between groups. If significant differences that could be 
confounding emerge, we will adjust for those variables or conduct stratified analyses. 
 
Analyses pertaining to primary outcomes of feasibility and acceptability of the intervention are 
primarily descriptive in nature (e.g., % completing the assigned intervention condition, % 
engaging in Snapchat messaging, ratings of intervention satisfaction).  
 
For analyses of other exploratory outcomes pertaining to cannabis use, alcohol, and drug use, 
we will first compare groups on cannabis quantity and frequency using basic two sample 
comparisons, operating on the pre-post differences (e.g., 3M-Baseline) to test for treatment 
effects. Our first choice will be a two-sample t-test to compare the pre-post differences between 
groups; considering non-parametric alternatives as needed. To assess changes in the 
dependent measures (e.g., use days, quantity, cannabis consequences) over follow-up we will 
use generalized linear mixed models (GLMMs) to jointly study the 1M and 3M outcomes, where 
possible, while adjusting for correlations between data points (e.g. repeated measurements on 
individuals). While adjustment for the baseline measurement is important for guarding against 
regression to the mean in RCTs195, using this baseline adjustment at every time point can result 
Cannabis use method, frequency and quantity 74 (modified) 
                                Smoke, Vape, and Dab (frequency, quantity) 
                              Drink and all methods combined (frequency, quantity) 
                              Number of days all methods combined 
                              Number of days vaped 
 
S,3M 
B,3M 
B,1M,3M 
1M 
Cannabis and Other Drug Use Frequency, Alcohol 
Quantity/Frequency(TLFB)67,68,69,70 
B,3M 
Brief Marijuana Adolescent Consequences Questionnaire (modified)71  
B,3M 
Impaired driving (modified) 72 
B,3M 
Primary Outcomes: Feasibility/Acceptability of Intervention 
Brief Intervention acceptability ratings (created for this study) 
I 
Snapchat acceptability ratings (created for this study) 
1M 
Brief intervention feasibility (e.g., % of participants completing brief 
intervention) 
I 
Snapchat health coaching feasibility (e.g., % of participants who 
complete process of adding health coach on Snapchat, % of participants 
who reply to at least 1 Snapchat message)  
I,1M 

 
Full Study Title: Harnessing social media to reduce cannabis use among adolescents and 
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in overestimation of the treatment effect when there are multiple follow-up points. It has been 
shown that baseline adjustment at only the first follow-up (1M in this case) corrects this 
overestimation while also guarding against regression to the mean, which will be our approach. 
Within this framework, we will conduct exploratory sub-analyses of whether the intervention 
effect is accumulating or weakening over time, by including time-by-group interactions. If the 
need is ascertained, we will control for confounders through their inclusion in the model as 
covariates. Our initial specification will be a linear mixed effects model (with Gaussian error 
distribution) with only a random intercept to capture within-individual dependence, but this 
choice will be scrutinized by examining model diagnostics and evaluating the veracity of 
modeling assumptions. As the need is ascertained, we will examine other distributional choices 
(e.g., Poisson, Negative Binomial) and more complex random effects structures (e.g., 
autoregressive). 
 
Other analyses. Moderation: To assess potential moderators we will include interactions with 
treatment group in the GLMM models above. Potential effect modifiers will include sex and age. 
Mediation: To test if cannabis motives and other variables (e.g., mental health symptoms) 
mediate treatment effects, we will use Imai’s causal mediation analysis framework, that is 
robustly implemented in the R package mediation. Traditional mediation analysis can be 
susceptible to bias; one source of this bias is the limitation to the classes of statistical models 
(e.g. the linear structural model of Baron and Kenny), that can be accommodated in traditional 
mediation analysis. Under technical assumptions of sequential ignorability, mediation effects are 
identifiable using Imai’s framework when models for the mediator and for the outcome that are 
non-linear, have discrete (nominal or ordinal) or continuous outcomes, include random effects, 
or are non-parametric. Engagement: Daily content ratings assessed by tallies from Snapchat 
messages logs (e.g., content, messages sent/received) will be calculated for different content 
areas (e.g., free time, stress, drug/alcohol-related) and assessed descriptively to see types of 
content with high response rates. Cost: To estimate intervention we will calculate summary 
statistics for the total intervention-specific costs and mean costs per participant, with confidence 
intervals. Costs will be reported with/without start-up and development, for example, including 
costs for recruiting and training coaches as well as their clinical supervision. As with prior work, 
net costs (savings) will be calculated by subtracting mean costs per participant in the control 
group from costs per participant for the assigned condition, also calculating the incremental cost 
effectiveness ratio (difference in mean cost of intervention vs. control divided by difference in 
mean effectiveness between intervention and control). Change in health benefits will be 
measured as the difference in cannabis consequences per month for the intervention vs. the 
control, expressed in dollars per consequence averted. Sensitivity analyses to evaluate 
alternate assumptions for estimated costs will be conducted. Given likely skewness, we will 
identify appropriate methods for generating confidence intervals that do not rely on the normal 
distribution (e.g., non-parametric boot-strapping). 
 
Power calculation and sample size  
Aim 2: The sample size is N = 100 (approximately 50 per group). For our primary 
analytic goal – examining feasibility and acceptability this is acceptable. With regard to other 
exploratory analyses estimating treatment effects – we are comparing two groups of size n = 50. 
Assuming no substantial covariate adjustment is needed, testing the significance of the 
treatment effect at a single time point will be equivalent to the comparison of two means, for 
which we use Cohen’s D (0.2: small, 0.5: medium, 0.8: large) as an effect size. Under the 
expected sample size, we will have sufficient power (>80%) to detect effects on both our 
cannabis and other substance use outcomes if d > 0.56, a medium effect size. Although the 
required effect size is non-negligible, the proposed pilot will provide the critical data necessary 
to inform the power analyses for a subsequent efficacy trial. While effect sizes from pilot studies 

 
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can have large standard errors and be unstable,202 we can use these pilot data to estimate point 
estimates and confidence intervals for our treatment effect sizes using the R package 
MBESS203. 
 
Data Confidentiality Plans 
     Our study team will take the following steps to minimize potential confidentiality breaches.  
As done in prior research and deemed HIPAA compliant by the IRBs at University of Michigan 
(UM) and HMC by use of a waiver of HIPAA authorization, minimal clinical data will be collected 
on ED patients who refuse to participate in the screening survey, and on ED patients who the 
research assistants fail to approach or contact (for remote recruitment). ED-based intervention, 
TLFB assessment sessions and any phone interviews (e.g., in the event a person cannot attend 
a follow-up in person, or during remote recruitment, we can administer the TLFB by phone) will 
be audio-recorded and will be destroyed after the conclusion of the study.  
     For each stage of the proposed research investigation, participants’ names and contact 
information will be stored in a secure, password-protected database, separate from their study 
data and only accessible to members of the research team for research purposes. Paper copies 
of signed consents and completed contact information forms will be stored in locked file 
cabinets only accessible to study staff, separate from study data. Any additional documents with 
identifying information linked to individual ID numbers will be only accessible by study staff and  
stored separate from study data, and in locked file cabinets or in restricted access folders on a 
secure server and destroyed at study completion. 
     Participants’ Snapchat IDs can be viewed on study cell phones; however, we will change the 
front page of coaches’ Snapchat apps to display generic participant IDs. Study cell phones and 
tablets (devices used for data collection and participant communication) will be password 
protected, use UM encryption (e.g., Hub) whenever possible, and only accessed by study staff 
who have completed and maintain mandatory training in the protection of human subjects and 
good clinical practices. 
  
Potential Risks  
Every effort will be made to ensure that study participants are protected from risks. The 
major risk for participants in this study is the violation of confidentiality. This risk is due to the 
disclosure of personal information regarding the use of an illegal substance, and is heightened 
due to the audio recording and use of social media. The informed consent will contain a 
statement about exceptions to confidentiality which include if the participant expresses 
suicidality, homicidality, or the physical or sexual abuse of a child. We expect that participants 
will not disclose such information in the context of Snapchat messaging, but should information 
to this effect be shared, we will provide appropriate referrals to resources and follow appropriate 
reporting procedures. Coaches will review limits of confidentiality at enrollment, will always 
notify participants when mandatory reporting or breaking of confidentiality is required, and will 
only disclose the minimum information necessary as required by law.   
Consent forms will also explain that participants’ activity on Snapchat is still accessible 
to Snapchat and subject to the app’s terms of use. We will also encourage participants to use a 
password/code on their phones and to view study messages in private spaces. Messages 
received on the Snapchat app are not viewable until the phone is unlocked, the app is opened, 
and the message is clicked on.  Thus message content will not be viewable: when a phone’s 

 
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screen is locked, in the notification bar, or without opening the app and choosing to look at the 
message. 
      
 Participants will be informed that we will take steps necessary to secure their data. 
Survey data collected will be stored in secure, password-protected databases on the secure U-
M network. When sending Snapchat messages, coaches will do so in private spaces using 
privacy screens where others who are not part of the research team could not see the data. 
Study cell phones and tablets used to send Snapchats will be password protected and use UM 
encryption (e.g., Hub) whenever possible, which is required of all mobile devices accessing the 
U-M network. Encryption programs used by UM enables safeguards against data compromise, 
malware, and ransomware and have a user portal to manage devices in case of theft, loss, or 
forgotten passwords. The computerized surveys are designed and administered using Qualtrics 
Research Suite through the University of Michigan (http://www.qualtrics.com/), which meets the 
HIPAA standards, and is where data will be stored based on study ID securely and separate 
from any identifying information.   
 
Protections Against Risk 
To minimize the risk of violating confidentiality, RAs will make every effort to ensure that 
study data are always kept confidential. Staff training procedures will include information about 
the importance of confidentiality and techniques to maintain confidentiality of all information 
reported by research participants. Staff will maintain human subjects and confidentiality 
certifications through the U-M Program for Education and Evaluation in Responsible Research 
and Scholarship system and will complete CITI Good Clinical Practice Training. Staff will be 
trained to conduct assessments and the initiation session where no one can overhear the 
conversation. Participants engaging in remote recruitment or follow-up activities will be 
encouraged to complete interviews and assessments in private locations where no one can 
overhear. Consent documents will fully explain the study procedures, potential risks, and 
potential benefits. At baseline, participants will also be asked to sign (for in-person recruitment) 
or verbally agree (for remote recruitment) to a User Safety Agreement that includes guidelines 
for interactions with coaches (e.g., agreeing not to send graphic images) based on a procedure 
used in our recently completed Facebook study. 
Unique identification numbers will be assigned to participants. Any data forms will be 
coded with this number, rather than with a name. Computer data files will be saved with 
passwords on a secured network, and will not contain names, birthdates, etc. See “Data 
Confidentiality Plan” above for further information on protection of participants’ data.   
Furthermore, as is standard practice, this study is covered by a Certificate of Confidentiality 
from the NIH to protect the confidentiality of our data from legal requests. Finally, specific 
information collected during this research study will not be available for use outside of research 
purposes. All data will be collected specifically for use on this project; however, de-identified 
data may be used for future research studies or distributed to another researcher for future 
research studies. 
 
Research staff and health coaches will be trained to respond to any emotional distress 
and to refer participants to appropriate resources as necessary.  All participants are free to 
terminate the study at any time or refuse to respond to any questionnaire item. The integration 
of motivational interviewing techniques will be non-confrontational and eschew any form of 
coercion or threat. Further, the risk of potential coercion is minimized by using standard 

 
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recruitment scripts to avoid undue influence.  All enrolled participants will also receive a 
substance use and mental health resources at baseline and follow-up. 
Regarding Snapchat messages, content of new messages do not appear on a 
participant’s notification screen and are only viewable when opened by the participant, taking at 
least 2-3 clicks before content is viewable. Because Snapchat use is common among emerging 
adults, it is unlikely that others will know that the youth is in a research study just by seeing 
Snapchat or a new notification on their phone. We will instruct participants to view messages 
from the study Snapchat account where they cannot be seen and to consider using a 
password/passcode on their cell phone. Snapchat messages are automatically deleted after 
viewing, with the exception of immediately re-viewing one message per day or if a participant 
chooses at the moment they receive it to save certain messages. Participants will be informed 
that they still risk having unread or saved messages viewed by others if anyone else accesses 
their cell phone or has access to their Snapchat account.  
Participants’ confidentiality will be breached by the research study only to protect the 
safety and welfare of research participants and only in accordance with state and federal law. 
Participants will be informed that coaches are not monitoring Snapchat 24/7 and that it should 
not be used for crisis situations, however staff will receive training in crisis assessment and risk 
management procedures in the unlikely event that participants reveal suicidal and/or homicidal 
ideation, or child physical/sexual abuse during study interactions (including Snapchat). If staff 
becomes aware of any of these issues, they will follow our standard risk assessment guidelines 
for in-person encounters and our standard written guidelines for attempting to contact 
participants remotely in the Snapchat messaging phase (e.g., message/text/email hotline 
number and by phone). In cases of psychiatric distress, staff are trained in strategies that 
include privately messaging/contacting the individual using MI and empathically encouraging 
use of referral information or other coping skills. Staff will immediately page on-call supervisors 
(including Dr. Bonar, Dr. Walton, or Dr. Carter) for consultation in cases where participants 
express moderate or high/imminent risk. Staff will also be trained to manage responses to 
potentially inappropriate messages from participants (e.g., asking on dates, sending explicit 
image).    
Regarding reporting of adverse events, we will follow the following procedures for UM 
IRBMED and the National Institute on Drug Abuse (NIDA), as specified in the Data Safety 
Monitoring Plan approved by the NIDA Project Officer (PO). Life-threatening serious adverse 
events (e.g., hospitalization as a result of suicidal ideation uncovered during study interaction) 
related to the study will be reported to IRBMED, NIDA, and the Medical Monitor no later than 72 
hours after learning of the event.  All other SAE’s (regardless of study relatedness) will be 
initially reported to the NIDA PO by phone/email no later than 72 hours after learning of the 
event.  Non-threatening potentially serious adverse events that are causally related to the 
research will be reported to the IRBMED within 14 days of learning of the event.  A summary of 
the serious adverse events that occurred during the previous year will be included in the annual 
progress report to NIDA.  We will follow the Hurley IRB guidelines for reporting both protocol 
deviations and adverse events to Hurley IRB, as well as follow the UM IRBMED guidelines for 
reporting protocol deviations to UM IRBMED. 
 
Potential Benefits 

 
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emerging adults in an urban emergency department 
 
 
13 
 
     We believe the potential for benefits outweighs the minimal risks associated with this study. It 
is possible that the assessments may be beneficial to all participants by asking them to review 
their substance use. Therefore, these assessments may actually serve as a very minimal 
intervention (as could any study with interviews regarding risky behaviors). Indeed, participants 
in our previous investigations have commented that they have found the questions to be helpful.  
Second, all participants will receive health and community resources (that will be updated from 
our prior studies), with referral information including suicide hotlines, and resources for 
substance use and mental health treatment.  
 
Importance of Knowledge to be Gained 
     Given that cannabis use behaviors often begin and reach a peak during adolescence and 
emerging adulthood, as well as the correlation with other substance use, the individual and 
societal cost of these behaviors, and the fact that many emerging adults may not receive 
traditional preventive services or access treatment, the development of effective targeted 
prevention programs is clearly needed. Given the current penetration of social media into the 
lives of young people, the potential reach provided by extending clinical-care interventions 
through a popular and widely used medium is significant. In addition, the ability to harness peer 
influences to create behavior change and the knowledge to be gained from this research is also 
significant. The risks to participants are reasonable in relation to the importance of this 
knowledge to be gained and potential public health impact of developing an effective program to 
reduce the use of and consequences associated with cannabis use among at-risk emerging 
adults. 
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