## Boston University

Activity Measure for Post Acute CareTM (AM-PAC)

Instruction Manual

AM-PAC Computerized Adaptive Testing AM-PAC CAT TM 

## 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.comAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 2 

## 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 Sc ores

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 .............. 23AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 3 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 suppor ted, in part, by the National Institute on Disability and Rehabilitation Re search (grant no. H133B990005) and the National Institute of Child Hea lth and Human Development (grant no. R01 HD43568). Development of t he 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.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 4 

### 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 Worl d Health Organization’s International Classification of Functioning, Disabi lity 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 ca re settings and consists of a comprehensive list of 240 functional acti vities (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 pro vided; therefore, the AM-PAC is the ideal measure for developing benchmarks and for examining functional outcomes over an episode of post acute care, as p atients move across care settings.

The AM-PAC instrument examines a set of functional activ ities that are likely to be encountered by most adults during daily routines withi n 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 organ ized 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 th e AM-PAC assess multiple aspects (i.e., difficulty, assistance, limitations) of an in dividual's ability to perform specific daily activities. IRT analyses were used to scale in dividual items in different functional areas along a continuum of item d ifficulty.

Initially, AM-PAC test items were administered to a lar ge sample of patients from different care settings with different diagnoses. Fa ctor 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 a nd Health (ICF). Geneva, Switzerland: World Health Organization; 2001.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 5 factors were verified by a confirmatory factor analysis (Ha ley et al. 2004) and defined as the three AM-PAC domains. Using Item Respon se Theory (IRT), items in each domain were scaled along a continuum of it em difficulty. Items that were redundant or did not fit the model were elimin ated. The remaining items formed the AM-PAC item banks, which included a wide ra nge 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. Th ree 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 b ased 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 abi lity level.

• Patients are not required to respond to irrelevant te st items.

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

• They promote efficient and reliable data entry, analysi s and management. AM-PAC data, along with patient data (a ge, 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 compreh ensive and precise point-of-care assessment of patient-related outcom es. It is being used with increasing frequency in the health field. This m ethod of patient assessment uses a computer to administer test items to patients and i s 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 th e test because the items are administered on the basis of the patient’s previou s responses. By avoiding the administration of large number of questionnaire i tems 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 q uestions, CAT approaches allow for efficient point-of-care collection of accurate outcome information that can feasibly be implemented in busy cli nical and research settings.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 6 The computer-based versions of the AM-PAC assess the three domains in all post acute settings (inpatient, outpatient and home car e).

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 bend ing, 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 hig her 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 h ave...

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

• getting up from the floor

• reaching overhead while standing, as if to pull a ligh t 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 mete rs) on the same level

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

• carrying something in both arms while climbing a fli ght of stairs (e.g., laundry basket

• climbing stairs step-over-step without a handrail (alt ernating 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 h ave...

• reaching behind your back to put a belt through the l oop

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

• unscrewing the lid off a previously unopened jar witho ut using devices

• tying shoes

How much HELP from another person do you currently need...AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 7 • putting on and taking off regular upper body clothin g

• 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 step s to another person

• following/understanding a 10 to 15 minute speech or p resentation (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 ot hers can understand you

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

• telling someone that what they are doing is botherin g 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 o f days

• reading and following complex instructions (e.g., di rections to operate a new appliance or for a new medication)

• looking up a phone number or address in the phone bo ok 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 p art of your weekly routine, (e.g., therapy, doctor appointment, or a soci al gathering with friends and family

• remembering to take medications at the appropriate t ime

• using a calendar, or weekly activity planner to keep track o f appointments and events

• putting together a shopping list of 10 to15 itemsAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 8 

### 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 Of fice 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 yo ur computer by using the set up program. Just follow steps 1-4, outlined bel ow.

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.’AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 9 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.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 10 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 alicense 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 ha ve 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: XXXXXXXAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 11 

### 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. Chang e the month by clicking the side arrows. Finally, click on the correct d ay.

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.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 12 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.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 13 3.2 AM-PAC CAT Questions-Respondent Instructions

The following introductory statement can be used to inst ruct 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 activi ties.

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 activit y.
2. Select ‘a lot’ if it is a struggle to do this activity a nd 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 compl eting 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 activit y. 2. Select ‘a lot’ if you are only able to do the activit y with considerable help from another person. 3. Select ‘a little’ if you do the activity almost by yo urself. 4. Select ‘none’ if you do the activity completely by yourse lf.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 14 3.3 Initial EvaluationAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 15 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).AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 16 You will complete the ‘living situation’ and ‘walking situation’ questions again, as they may have changed from the initial visit.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 17 

### Section 4: AM-PAC CAT: Reports and Interpreting Sc ores

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.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 18 4.2 Interpreting Basic Mobility Scores

It may be helpful to have a context for interpreting A M-PAC scores. The table below relates AM-PAC Basic Mobility scores to clinically-sig nificant functional stages. These stages were identified using data from ove r 1,000 cases across post acute care settings. The stages represent activities that are increasingly more difficult—from activities within a room or buildi ng, to activities outside, to recreation or sports. The level of difficulty exhibited by most patients with Standardized Scores in the specified ranges is described fo r each functional stage.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 19 4.3 Interpreting Daily Activity Scores

It may be helpful to have a context for interpreting A M-PAC scores. The table below provides AM-PAC Daily Activity scores to clinically-si gnificant functional categories of basic and instrumental activities of daily l iving and fine motor activities. These categories were identified using dat a from over 1,000 cases across post acute care settings. The level of difficulty expe rienced by most patients with standardized scores within the specified ran ges is described for each functional stage.

Daily ActivityAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 20 4.4 Interpreting Applied Cognitive Scores

It may be helpful to have a context for interpreting A M-PAC scores. The table below provides AM-PAC Cognitive scores to clinically-signi ficant functional categories of communication, information retrieval and co mplex processes. These categories were identified using data from over 1, 000 cases across post acute care settings. The level of difficulty experienced b y most patients with standardized scores within the specified ranges is described for each functional stage.

Communication Information retrieval Complex processesAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 21 4.5 Facility Reports: Aggregate Data

The PC version of the AM-PAC CAT provides an aggregat e report of all the AMPAC assessment completed on the PC. The report provide s a summary of the following areas: general information, severity, body par t/impairment group, payment sources, condition, and AM-PAC average score for ea ch of the three domains. The user chooses a time period for generating the aggregate report. The PC aggregate report contains only data entered int o 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 report ing of aggregate data.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 22 

### 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 availabl e 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 availabl e and can be printed. » AM-PAC data are stored on a server that can handl e multiple clinical sites. » AM-PAC data can be merged across sites to produce a n aggregate report. » AM-PAC data can be integrated with facility clini cal and/or financial data. » CREcare data management and analysis services are a vailable with this option.

NOTE: this option is best suited for organizations with multiple clinical sites where data are merged across an organization.AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 23 

### Section 6: References

6.1 AM-PAC and AM-PAC CAT Annotated Bibliography

Published work on the AM-PAC is included in the fol lowing citations. Work is ongoing.

Jette A, Haley S, Tao W, Ni P, Meyers D, Zurek M. Prospe ctive evaluation of the AM-PAC-CAT in outpatient rehabilitation settings Physical Therapy (in press).

This prospective study evaluated the Activity Measure for PostAcute 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 functi onal 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 reliabili ty of the AM-PAC. Results demonstrate acceptable reliability with the follo wing intraclass correlation coefficients: 1.) test-retest summary scores for each of th e 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 out come instruments used in post acute care. Health Care Services Review 2003;24 (3):45-60.

This article presents an empirical comparison of four funct ional outcome instruments used in PAC with respect to their content, br eadth of coverage, and measurement precision. Results illustrate limitations in t he range of content, breadth of coverage, and measurement precision in each ou tcome instrument. None appears well-equipped to meet the challenge of m onitoring quality and functional outcomes across settings where PAC is provided. L imitations in existing assessment methodology have stimulated the developme nt of more comprehensive outcome assessment systems specifically for monitori ng the quality of services provided to PAC patients.

Haley SM, Coster WJ, Andres PL, Ludlow LH, Ni P, Bond T LY, Sinclair SJ, Jette AM. Activity outcome measurement for post acute care. Med ical Care 2004;42 (suppl. 1):I-49-I61.

This study presents results from an initial exploratory f actor analysis of AM-PAC items. Three distinct, interpretable factors were ident ified and accounted for 72% of the variance: Applied Cognition (44%), Personal Car e & Instrumental ActivitiesAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 24 (19%), and Physical & Movement Activities (9%); these 3 act ivity factors were verified by a confirmatory factor analysis. Scaling assumption s were met for each factor in the total sample and across diagnostic groups. I nternal consistency reliability was high for the total sample (Cronbach al pha = 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 mo dified parallel analyses supported the unidimensionality and goodness of fit of each unique activity domain.

Coster WJ, Haley, SM Andres PL, Ludlow LH, Bond T. Refi ning 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 com pared 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. A DL and IADL items from existing rehabilitation outcomes instruments that d epend on skilled upper limb and hand were located along a single continuum, a long 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 Instr umental 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 illust ration 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-PA C). Inpatient and community-based short forms and CAT applications were devel oped for each of 3 activity domains (physical & mobility, personal care & inst rumental, applied cognition) using item pools constructed from new items and items from existing post acute care instruments. Simulated CAT scores correlat ed 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 commun ity settings also provided good estimates of the AM-PAC item pool scores f or the physical & movement and personal care & instrumental domains, but w ere less consistent in the applied cognition domain. Confidence intervals arou nd individual scores wereAM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 25 greater in the short forms than for the CATs. The stron g relationship between CAT and item pool scores demonstrate the CAT's ability to select specific items to match individual responses. The CAT may have addition al 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 poolin g procedures to develop inpatient- and community-based short forms for ea ch of 3 activity domains: physical & movement, applied cognition, and perso nal care & instrumental. Items consisted of new items and items from existing post acute care instruments. Items were selected for inclusion on t he 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 th e 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 rehab ilitation functional outcome instruments currently in use within the rehabilitation f ield to assess Activity and Participation domains as defined by the International Classification of Function, Disability, and Health. There is an emphasis on how cont emporary 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 sco pe, accurate, allow for compatibility across instruments, and are sensitive to cl inically 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 Activi ty Measure for Post Acute Care (AM-PAC) compared to the Functional Indepen dence Measure (FIM) across a 12-month period after discharge from rehabilita tion hospital. All 3 AM-AM-PAC Computerized Adaptive Testing Manual Personal Computer Version (v.1) Last revision: 2/8/2007 © 2007, Trustees for Boston University, under license to C REcare, LLC. All rights reserved

. 26 PAC scales were sensitive to both positive and negative chang e across the follow-up period. Standardized response means for the AM-PAC were consistently larger than for the FIM across patient and seve rity groups. A greater percentage of patients showed positive change that exceede d the minimal detectable change on the AM-PAC than on the FIM both6- 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 r espondent effects. American Journal of Physical Medicine and Rehabilitation 2006;85:747-755.

This prospective, cohort study compares proxy vs. patient repo rt in hospital and community settings. Intraclass correlation coefficients on su mmary scores between patient and proxy report were as follows: physica l and mobility ICC = 0.92; personal care and instrumental ICC = 0.93; and a pplied cognition ICC = 0.77. Graphic approaches helped interpret differences in separate analyses of clinician and family agreement are also presented as a u seful method for interpreting agreement data that may be useful in det ermining the meaningfulness of the amount and direction of interresp ondent 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 C REcare, LLC. All rights reserved

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