Boston University 

Activity Measure for Post Acute CareTM (AM-PAC) 

Instruction Manual 

AM-PAC Computerized Adaptive Testing 

AM-PAC CATTM 

Personal Computer Version 

Basic Mobility, Daily Activity and 

Applied Cognitive Functional Domains 

 

Developed by: 

Alan Jette, PT, PhD 

Stephen M. Haley, PT, PhD 

Wendy Coster, OT, PhD 

Pengsheng Ni, MD, MPH 

Boston University 

Health and Disability Research Institute 

Distributed by CREcare, LLC 

Email: information@crecare.com 

Website: www.crecare.com 
AM-PAC Computerized Adaptive Testing Manual 

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AM-PAC Computerized Adaptive Testing (AM-PAC CAT) 

Manual Personal Computer Version 

Table of Contents

 Page 

Section 1: Introduction 

 

 1.1 Activity Measure for Post Acute Care (AM-PAC) ................. 4 

 1.2 AM-PAC Computerized Adaptive Testing ......................... 5 

1.3 AM-PAC CAT Functional Domains ................................. 6 

Section 2: AM-PAC CAT Software 

2.1 Hardware and Software Requirements .............................. 8 

2.2 Downloading and Installing AM-PAC CAT Software ............. 8 

 

Section 3: Administering the AM-PAC CAT 

3.1 Patient Demographic Information............................................. 11 

3.2 AM-PAC CAT Questions-Respondent Instructions ................. 13 

 3.3 Initial Evaluation .......................................................... 14 

 3.4 Follow Up Evaluation ..................................................... 15 

 

Section 4: AM-PAC CAT: Reports and Interpreting Scores 

4.1 View and Print Reports .................................................. 17 

 4.2 Interpreting Basic Mobility Scores .................................... 18 

4.3 Interpreting Daily Activity Scores ...................................... 19 

4.4 Interpreting Applied Cognitive Scores ................................ 20

4.5 Facility Reports: Aggregate Data ..................................... 21 

Section 5: AM-PAC CAT Computer Versions 

5.1 Freestanding PC and Web/Server Versions ........................ 22 

Section 6: References 

6.1 AM-PAC and AM-PAC CAT Annotated Bibliography .............. 23 
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Acknowledgements 

Work to develop the Boston University Activity Measure for Post Acute Care 

(AM-PAC) was undertaken at the Boston University Research and Training 

Center for Measuring Rehabilitation Outcomes and supported, in part, by the 

National Institute on Disability and Rehabilitation Research (grant no. 

H133B990005) and the National Institute of Child Health and Human 

Development (grant no. R01 HD43568). Development of the AM-PAC Outpatient 

Short Forms for use in outpatient settings was supported in part by an 

Independent Scientist Award (K01 HD45354-01) received by Stephen Haley, 

PhD.
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Section 1: Introduction 

 

 

1.1 Activity Measure for Post Acute Care (AM-PAC)TM 

 

The Boston University Activity Measure for Post Acute Care (AM-PAC)TM is an 

activity limitations instrument developed using the World Health Organization’s 

International Classification of Functioning, Disability and Health (ICF). 

According to the ICF, an activity limitation is defined as “difficulty in the execution 

of a task or action by an individual.” 1 The AM-PACTM was developed as a 

functional outcomes system that can be used across post acute care settings 

and consists of a comprehensive list of 240 functional activities (i.e., the item 

bank). It measures functional outcome by using contemporary measurement 

techniques, such as Item Response Theory (IRT), to overcome the limitations of 

traditional functional outcome measures (Jette and Haley, 2005). Unlike these 

traditional functional outcome measures which are disease, condition, or settingspecific, the AM-PAC was designed to be used across patient diagnoses, 

conditions and settings where post acute care is being provided; therefore, the 

AM-PAC is the ideal measure for developing benchmarks and for examining 

functional outcomes over an episode of post acute care, as patients move across 

care settings. 

The AM-PAC instrument examines a set of functional activities that are likely to 

be encountered by most adults during daily routines within the context of either 

an inpatient episode of care or outpatient post acute services. We have defined 

functional activity as the execution of discrete daily tasks. Because functional 

activity is multidimensional, AM-PAC item banks are organized into three 

functional areas: Basic Mobility (101 items), Daily Activity (70 items), and 

Applied Cognitive (69 items). Items for the AM-PAC have been drawn from two 

sources: (1) a set of new items that examine the functional content domains 

listed above; and (2) items from existing outcome instruments used in 

rehabilitation and post acute programs. The items in the AM-PAC assess multiple 

aspects (i.e., difficulty, assistance, limitations) of an individual's ability to perform 

specific daily activities. IRT analyses were used to scale individual items in 

different functional areas along a continuum of item difficulty. 

Initially, AM-PAC test items were administered to a large sample of patients from 

different care settings with different diagnoses. Factor analytic work identified 

three distinct, interpretable factors that accounted for 72% of the variance: 

Applied Cognition (44%), Daily Activities (19%) and Basic Mobility (9%). These 

_________________________________________________________________ 

1. International Classification of Functioning, Disability and Health (ICF). Geneva, 

Switzerland: World Health Organization; 2001. 
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factors were verified by a confirmatory factor analysis (Haley et al. 2004) and 

defined as the three AM-PAC domains. Using Item Response Theory (IRT), 

items in each domain were scaled along a continuum of item difficulty. Items that 

were redundant or did not fit the model were eliminated. The remaining items 

formed the AM-PAC item banks, which included a wide range of items calibrated 

along a continuum of difficulty. 

The instrument can be administered using responses coming directly from a 

patient, by professional judgment, or proxy report. Three AM-PAC versions are 

currently available: 

1) Outpatient short forms 

2) A free-standing computer version 

3) A Web-based computer version 

1.2 AM-PAC Computerized Adaptive Testing 

Computer Adaptive Testing (CAT) uses a computer algorithm to pre-select the 

items that will be administered to a specific patient based on responses to 

previous items. CAT-based instruments have the following advantages: 

• They reduce test burden while increasing test precision because test 

items are selected to match the patient's functional ability level. 

• Patients are not required to respond to irrelevant test items. 

• It is easy to integrate assessment into clinical work flow. 

• They promote efficient and reliable data entry, analysis and 

management. AM-PAC data, along with patient data (age, gender, 

diagnosis, time since onset, surgical status, severity and insurance), are 

entered and stored in a database on the local computer or on a server. 

• It only takes two minutes to complete each domain. 

• They can include patient satisfaction questions. 

 

CAT is an outcome measurement approach designed for comprehensive and 

precise point-of-care assessment of patient-related outcomes. It is being used 

with increasing frequency in the health field. This method of patient assessment 

uses a computer to administer test items to patients and is adaptive in the sense 

that each ‘test’ is tailored to the unique level of each patient. Each person who 

takes an adaptive test is taking a different version of the test because the items 

are administered on the basis of the patient’s previous responses. By avoiding 

the administration of large number of questionnaire items and by selecting only 

those questions from a large ‘item-bank’ that provide the maximum amount of 

information based upon a person’s responses to previous questions, CAT

approaches allow for efficient point-of-care collection of accurate outcome 

information that can feasibly be implemented in busy clinical and research 

settings. 
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The computer-based versions of the AM-PAC assess the three domains in all 

post acute settings (inpatient, outpatient and home care). 

1.3 AM-PAC CAT Functional Domains 

The AM-PAC Basic Mobility domain includes 101 items that address basic 

movement and physical functioning activities, such as bending, walking, carrying, 

and climbing stairs. The AM-PAC Daily Activity domain includes 70 items that 

address basic self care and instrumental activities of daily life. The AM-PAC 

Applied Cognitive domain includes 69 items that access higher level cognitive 

functions that are necessary to live independently. 

Listed below are examples of items from each of the AM-PAC domains. 

Basic Mobility Domain:

How much DIFFICULTY do you (or the patient) currently have... 

• moving from lying on your back to sitting on side of the bed 

• getting up from the floor 

• reaching overhead while standing, as if to pull a light cord 

• using an escalator 

• going up and down a flight of stairs inside, using a handrail 

• walking around inside a building (50 ft, or 16 meters) on the same level 

• going up and down three flights of stairs inside, using a handrail 

• carrying something in both arms while climbing a flight of stairs (e.g., 

laundry basket 

• climbing stairs step-over-step without a handrail (alternating feet) 

• walking quickly indoors to answer the telephone 

How much HELP from another person do you currently need ... 

• climbing a full flight of stairs without a railing 

• moving from a bed to a chair 

 

Daily Activity Domain: 

How much DIFFICULTY do you (or the patient) currently have... 

• reaching behind your back to put a belt through the loop 

• inserting a key in a lock and turning it to unlock the door 

• unscrewing the lid off a previously unopened jar without using devices 

• tying shoes 

 

How much HELP from another person do you currently need... 
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• putting on and taking off regular upper body clothing 

• taking care of personal grooming 

Applied Cognitive Domain: 

How much DIFFICULTY do you (does the patient) currently have... 

• explaining how to do something involving several steps to another person 

• following/understanding a 10 to 15 minute speech or presentation (e.g. a 

lesson at a place of worship, a guest lecture at a senior center) 

• describing something that has happened to you so that others can 

understand you 

• carrying on a conversation with a small group (e.g., family or a few friends) 

• telling someone that what they are doing is bothering you (e.g., 

interrupting or making noise that is distracting) 

• getting to know new people 

• reading a long book (over 100 pages) over a number of days 

• reading and following complex instructions (e.g., directions to operate a 

new appliance or for a new medication) 

• looking up a phone number or address in the phone book or in your own 

address book 

• filling out a long form (e.g., insurance forms or an application for services) 

• writing down a short message or note 

• planning for and keeping appointments that are not part of your weekly 

routine, (e.g., therapy, doctor appointment, or a social gathering with 

friends and family 

• remembering to take medications at the appropriate time 

• using a calendar, or weekly activity planner to keep track of appointments 

and events 

• putting together a shopping list of 10 to15 items 

 
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Section 2: AM-PAC CAT Software 

2.1 Hardware and Software Requirements 

 

PC software and hardware requirements: Microsoft Windows XP, 512 MB of 

RAM and 10 GB of available hard drive space, Microsoft Office 2003. Microsoft 

Access is not needed to run the AM-PAC CAT program, but is needed to see 

data elements.

2.2 Downloading and Installing AM-PAC CAT Software 

A trial version of the AM-PAC CAT is available, free of charge, for 7 days. When 

you purchase the AM-PAC CAT, you will receive an activation code that allows 

access for 365 days. AM-PAC CAT software is available for download at: 

www.crecare.com

First, you need to install the AM-PAC CAT software on your computer by using 

the set up program. Just follow steps 1-4, outlined below.

1. Click on ‘next.’

2. Select the file where you 

want to save the program 

and click on ‘next.’ 

3. Click on ‘next.’ 

4. Click on 

‘finish.’
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Now you need to activate the product and you 

need a product activation code. Click on the 

activation site (www.crecare.com/activate) or 

copy it into your browser. 

You will see a registration screen. 

Complete the fields and click on 

‘submit.’ 

You will see a ‘thank you’ screen 

notifying you that an email has been 

sent with your activation code.
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To the right, you can see 

an example of the email 

that you will receive with 

your activation code. 

Copy the activation code into the blank field 

and click on ‘activate.’

Review the term of agreement and 

click on ‘I accept’. 

By clicking the ‘Upgrade Now’

button, you will be brought to a web 

page where you can purchase a 

license for one year’s use of the AMPAC PC software. 

The ‘License Manager’ button will 

expose the product number you will 

use to upgrade. 

Thank you for completing the AM-PACTM Product Activation process. 

Please use the code below to activate the AM-PAC. This code will activate 

the AM-PAC application for the next 7 days. If you have purchased the 

AM-PAC 1 year subscription, a new Activation Code will be sent to this 

same email address within the next 24 hours. 

Product Serial Number: XXXXXXXX 

Activation Code: XXXXXXX 
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Section 3: Administering the AM-PAC CAT

3.1 Patient Demographic Information 

Enter the ‘patient ID’ number. 

If the ‘Patient ID’ number has not 

been used, the program will 

recognize that this is the patient’s 

first visit and you will enter the 

patient’s demographic and 

background information. 

The ‘Date’ field will be 

automatically entered. 

To enter the ‘Date of Birth’, use 

the calendar that is available when 

you click on the drop down menu. 

Change the year by clicking the up or down arrows. Change the month by 

clicking the side arrows. Finally, click on the correct day. 

Use the drop down menu to 

select the ‘Gender’. 

For ‘type of condition’, click on 

the drop down menu to view 

options and select the primary 

condition that brought the patient 

to therapy. If you select 

‘Orthopedic’, click on the box 

next to the body part involved. 
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Enter ‘time since onset’ in 

number of days. 

Use the drop down menu to 

identify if there was a ‘previous 

surgery’ for the primary condition 

that brought the patient to therapy. 

Use the drop down menu to select 

from the following descriptions of 

‘severity’ of the primary condition: 

Not severe 

Mildly severe 

Moderately severe 

Extremely severe 

Finally, use the drop down menu to 

select ‘type of insurance 

coverage’ from the list. 

Click on ‘next’. 

Click on the circle next to the best 

description of ‘living situation’

and ‘walking situation’. 

Click on ‘start’ and begin 

answering functional questions. 
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3.2 AM-PAC CAT Questions-Respondent Instructions 

The following introductory statement can be used to instruct patients or clinicians 

on how to complete the AM-PAC Outpatient Short Form:

“Please read each question and use the mouse, keyboard or stylus to click 

on the box under the statement that best describes your (or the patient’s) 

current level of difficulty in doing each activity. 

Some questions ask how much difficulty you have doing activities. 

For example, for the question: 

How much difficulty do you have doing light housework: 

1. Select ‘can’t do’ if you are not able to do this activity. 

2. Select ‘a lot’ if it is a struggle to do this activity and you require a 

great effort and/or time. 

3. Select ‘a little’ if you manage to do the activity, but notice that it 

takes more effort and/or time than you think it should. 

4. Select ‘none’ if you do not experience any problems completing 

this activity. 

Other questions ask how much help or assistance you need to do 

activities. 

For example, for the question: 

How much help from another person do you need to climb one flight of 

stairs without a railing: 

1. Select ‘total’ if you are unable to do this activity. 

2. Select ‘a lot’ if you are only able to do the activity with 

considerable help from another person. 

3. Select ‘a little’ if you do the activity almost by yourself. 

4. Select ‘none’ if you do the activity completely by yourself. 
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3.3 Initial Evaluation 
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3.4 Follow Up Evaluation 

If a patient has a completed AMPAC CAT assessment in the 

system, the computer will 

recognize the ‘Patient ID.’ You 

can view the patient report to 

ensure that the general information 

is accurate. 

You will be asked to enter the 

‘following visit’ date. Enter the correct 

year, month and date by using the drop 

down calendar (similar to entering date 

of birth).
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You will complete the ‘living 

situation’ and ‘walking situation’

questions again, as they may have 

changed from the initial visit.
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Section 4: AM-PAC CAT: Reports and Interpreting Scores 

4.1 View and Print Reports 

AM-PAC CAT formats provide 

individual patient reports. These 

reports summarize patients' 

general information and provide 

scale scores and standard error 

(S.E.) for each domain assessed. 

Click on one of the upper tabs--

General Information, Basic 

Mobility, Daily Activity or 

Applied Cognitive--to view 

results. 

Reports can be viewed and 

printed after initial and follow up 

visits. Follow up visit reports 

display the results of the first and 

last visits side-by-side for 

comparison. 

You can print patient reports. 

Patient responses to individual 

items can be viewed by clicking 

on ‘Actually Response.’ 

AM-PAC CAT items and patient 

responses for first and last visits. 
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4.2 Interpreting Basic Mobility Scores 

It may be helpful to have a context for interpreting AM-PAC scores. The table 

below relates AM-PAC Basic Mobility scores to clinically-significant functional 

stages. These stages were identified using data from over 1,000 cases across 

post acute care settings. The stages represent activities that are increasingly 

more difficult—from activities within a room or building, to activities outside, to 

recreation or sports. The level of difficulty exhibited by most patients with 

Standardized Scores in the specified ranges is described for each functional 

stage. 
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4.3 Interpreting Daily Activity Scores 

It may be helpful to have a context for interpreting AM-PAC scores. The table 

below provides AM-PAC Daily Activity scores to clinically-significant functional 

categories of basic and instrumental activities of daily living and fine motor 

activities. These categories were identified using data from over 1,000 cases 

across post acute care settings. The level of difficulty experienced by most

patients with standardized scores within the specified ranges is described for 

each functional stage. 

 

Daily Activity 
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4.4 Interpreting Applied Cognitive Scores

It may be helpful to have a context for interpreting AM-PAC scores. The table 

below provides AM-PAC Cognitive scores to clinically-significant functional 

categories of communication, information retrieval and complex processes. 

These categories were identified using data from over 1,000 cases across post 

acute care settings. The level of difficulty experienced by most patients with 

standardized scores within the specified ranges is described for each functional 

stage. 

Communication 

Information 

retrieval

Complex processes 
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4.5 Facility Reports: Aggregate Data 

The PC version of the AM-PAC CAT provides an aggregate report of all the AMPAC assessment completed on the PC. The report provides a summary of the 

following areas: general information, severity, body part/impairment group, 

payment sources, condition, and AM-PAC average score for each of the three 

domains. The user chooses a time period for generating the aggregate report. 

The PC aggregate report contains only data entered into the personal computer. 

No additional data are included in the analysis. 

Clients using the computer-based format server option can take advantage of 

CREcare reporting services that provide detailed reporting of aggregate data. 
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Section 5: AM-PAC CAT Computer Versions 

5.1 Freestanding PC and Web/Server Versions 

AM-PAC CAT Format Options 

There are two options available to AM-PAC CAT users: a version that runs on a 

freestanding personal computer and a web-based or server version. The tables 

below summarize the benefits of each. 

Stand-alone personal computer version 

 » Users download the AM-PAC computer program onto a personal computer. 

 » AM-PAC individual patient reports are available and can be printed. 

 » AM-PAC data are stored locally on the hard drive. 

 » AM-PAC data stored on computer can be viewed as an aggregate report. 

 » AM-PAC data is stored in an Access database. 

NOTE: this option is best suited for individual clinical sites where data are entered 

on a single computer. 

Server-based version 

 » CREcare helps install the AM-PAC on your server or provides remote access. 

 » AM-PAC individual patient reports are available and can be printed. 

 » AM-PAC data are stored on a server that can handle multiple clinical sites. 

 » AM-PAC data can be merged across sites to produce an aggregate report. 

 » AM-PAC data can be integrated with facility clinical and/or financial data. 

 » CREcare data management and analysis services are available with this option.

NOTE: this option is best suited for organizations with multiple clinical sites where 

data are merged across an organization. 

 
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Section 6: References 

6.1 AM-PAC and AM-PAC CAT Annotated Bibliography 

Published work on the AM-PAC is included in the following citations. Work 

is ongoing. 

 

Jette A, Haley S, Tao W, Ni P, Meyers D, Zurek M. Prospective evaluation of the 

AM-PAC-CAT in outpatient rehabilitation settings Physical Therapy (in press). 

This prospective study evaluated the Activity Measure for Post Acute Care (AMPAC) “item bank” and computerized adaptive testing (CAT) assessment platform 

(AM-PAC-CAT) in orthopedic outpatient physical therapy settings. 

Andres P, Haley SM, Ni PS. Are patient-reported functional measures reliable in 

monitoring post acute outcomes? American Journal of Physical Medicine and 

Rehabilitation 2003;82(8):614-21. 

This study examined test-retest and subject-proxy reliability of the AM-PAC. 

Results demonstrate acceptable reliability with the following intraclass correlation 

coefficients: 1.) test-retest summary scores for each of the three domains 

ranged between 0.91 and 0.97; 2.) subject proxy summary scores for each of the 

three domains ranged between 0.68 and 0.90. 

Jette AM, Haley SM, Ni P. A comparison of functional outcome instruments used 

in post acute care. Health Care Services Review 2003;24 (3):45-60. 

This article presents an empirical comparison of four functional outcome 

instruments used in PAC with respect to their content, breadth of coverage, and 

measurement precision. Results illustrate limitations in the range of content, 

breadth of coverage, and measurement precision in each outcome instrument. 

None appears well-equipped to meet the challenge of monitoring quality and 

functional outcomes across settings where PAC is provided. Limitations in 

existing assessment methodology have stimulated the development of more 

comprehensive outcome assessment systems specifically for monitoring the 

quality of services provided to PAC patients. 

Haley SM, Coster WJ, Andres PL, Ludlow LH, Ni P, Bond TLY, Sinclair SJ, Jette 

AM. Activity outcome measurement for post acute care. Medical Care 2004;42 

(suppl. 1):I-49-I61. 

This study presents results from an initial exploratory factor analysis of AM-PAC 

items. Three distinct, interpretable factors were identified and accounted for 72% 

of the variance: Applied Cognition (44%), Personal Care & Instrumental Activities 
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(19%), and Physical & Movement Activities (9%); these 3 activity factors were 

verified by a confirmatory factor analysis. Scaling assumptions were met for each 

factor in the total sample and across diagnostic groups. Internal consistency 

reliability was high for the total sample (Cronbach alpha = 0.92 to 0.94), and for 

specific diagnostic groups (Cronbach alpha = 0.90 to 0.95). Rasch scaling, 

residual factor, differential item functioning, and modified parallel analyses 

supported the unidimensionality and goodness of fit of each unique activity 

domain. 

Coster WJ, Haley, SM Andres PL, Ludlow LH, Bond T. Refining the conceptual 

basis for rehabilitation outcome measurement: personal care and instrumental 

activities domain. Medical Care 2004;42 (suppl. 1):I-62 - I-72. 

This study examined the dimensional structure and content coverage of a 

Personal Care and Instrumental Activities item set and compared ADL and IADL 

items items from existing instruments (FIM, MDS, MDS-PAC, OASIS, PF-10) to a 

set of new items (AM-PAC) as measures of this domain. ADL and IADL items 

from existing rehabilitation outcomes instruments that depend on skilled upper 

limb and hand were located along a single continuum, along with the new items 

from the AM-PAC that addressed gaps in content. Results support the validity of 

the proposed definition of the Personal Care and Instrumental Activities 

dimension of function as a guide for future development of rehabilitation outcome 

instruments, such as linked, setting-specific short forms and computerized 

adaptive testing approaches. 

Haley SM, Coster WJ, Andres PL, Kosinski M, Ni P. Score comparability of 

short-forms and computerized adaptive testing: an illustration with the Activity 

Measure for Post Acute Care (AM-PAC) Archives of Physical Medicine & 

Rehabilitation 2004;85:661-666,. 

This study compared simulated short-form and computerized adaptive testing 

(CAT) scores to scores obtained from complete item sets for each of the 3 

domains of the Activity Measure for Post Acute Care (AM-PAC). Inpatient and 

community-based short forms and CAT applications were developed for each of 

3 activity domains (physical & mobility, personal care & instrumental, applied 

cognition) using item pools constructed from new items and items from existing 

post acute care instruments. Simulated CAT scores correlated highly with score 

estimates from the total item pool in each domain (4- and 6-item CAT r values 

ranged from .90-.95; 10-item CAT r values ranged from .96-.98). Scores on the 

10-item short forms constructed for inpatient and community settings also 

provided good estimates of the AM-PAC item pool scores for the physical & 

movement and personal care & instrumental domains, but were less consistent in 

the applied cognition domain. Confidence intervals around individual scores were 
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greater in the short forms than for the CATs. The strong relationship between 

CAT and item pool scores demonstrate the CAT's ability to select specific items 

to match individual responses. The CAT may have additional advantages over 

short forms in practicality, efficiency, and the potential for providing more precise 

scoring estimates for individuals. 

Haley SM, Andres PL, Coster WJ, Kosinski M, Ni P, Jette AM. Short-form 

activity measures for post acute care (AM-PAC). Archives of Physical Medicine 

& Rehabilitation 85;649-660, 2004. 

This study used item response theory (IRT) and item pooling procedures to 

develop inpatient- and community-based short forms for each of 3 activity 

domains: physical & movement, applied cognition, and personal care & 

instrumental. Items consisted of new items and items from existing post acute 

care instruments. Items were selected for inclusion on the short forms to 

maximize content coverage and information value of items across the range of 

content and to minimize ceiling and floor effects. We were able to match the 

distribution of sample scores with very good item precision for 1 of the constructs 

(physical & movement); the other 2 domains (personal care & instrumental, 

applied cognition) were more challenging because of the variability in patient 

recovery and ceiling effects. 

 

Jette AM, Haley SM. Contemporary measurement techniques for rehabilitation 

outcome assessment. Journal of Rehabilitation Medicine 2005; 37: 339-345. 

This paper reviews the limitations of traditional rehabilitation functional outcome 

instruments currently in use within the rehabilitation field to assess Activity and 

Participation domains as defined by the International Classification of Function, 

Disability, and Health. There is an emphasis on how contemporary 

measurement techniques, such as item response theory methods combined with 

computer adaptive testing methodology, can be applied in rehabilitation to design 

functional outcome instruments that are comprehensive in scope, accurate, allow 

for compatibility across instruments, and are sensitive to clinically important 

change without sacrificing their feasibility. 

Coster W, Haley S, Jette A: Measuring patient-reported outcomes after discharge 

from inpatient rehabilitation settings. J of Rehabilitation Medicine 2006;38:237-

242. 

This study examines the sensitivity of the Short Form Activity Measure for Post 

Acute Care (AM-PAC) compared to the Functional Independence Measure (FIM) 

across a 12-month period after discharge from rehabilitation hospital. All 3 AM-
AM-PAC Computerized Adaptive Testing Manual 

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© 2007, Trustees for Boston University, under license to CREcare, LLC. All rights reserved. 

26

PAC scales were sensitive to both positive and negative change across the 

follow-up period. Standardized response means for the AM-PAC were 

consistently larger than for the FIM across patient and severity groups. A greater 

percentage of patients showed positive change that exceeded the minimal 

detectable change on the AM-PAC than on the FIM both 6- and 12-month followups. 

Haley SM, Ni P, Coster WJ, Black-Schaffer R, Siebens H, Tao W. Agreement in 

functional assessment: graphical approaches to displaying respondent effects. 

American Journal of Physical Medicine and Rehabilitation 2006;85:747-755. 

This prospective, cohort study compares proxy vs. patient report in hospital and 

community settings. Intraclass correlation coefficients on summary scores 

between patient and proxy report were as follows: physical and mobility ICC = 

0.92; personal care and instrumental ICC = 0.93; and applied cognition ICC = 

0.77. Graphic approaches helped interpret differences in separate analyses of 

clinician and family agreement are also presented as a useful method for 

interpreting agreement data that may be useful in determining the 

meaningfulness of the amount and direction of interrespondent variation. 
AM-PAC Computerized Adaptive Testing Manual 

Personal Computer Version (v.1) 

 Last revision: 2/8/2007 

© 2007, Trustees for Boston University, under license to CREcare, LLC. All rights reserved. 

27