Activity Measure for Post-Acute Care (AM-PAC)
Background Information
The AM-PAC was developed at the Boston University Health and Disability Institute under the leadership of Drs. Alan Jette and Stephen Haley. First a comprehensive list of functional items was developed using the International Classification of Functioning and Disability and with input from patients and expert clinicians. These test items were administered to a large sample of patients from different care settings with a wide range of diagnoses. Using Item Response Theory (IRT) the test items were scaled to provide an estimate of a patient's functional ability. The paper short-form version of the AM-PAC was developed from these test items. The computer-based version of the AM-PAC uses Computer Adaptive Testing (CAT) to select test items that are most appropriate for an individual patient, which increases measurement precision while minimizing respondent burden.
What advantages does the AM-PAC offer over traditional measures?
The AM-PAC is comprised of test items that cover a wide range of function--from "rolling over in bed" to "running 5 miles." Because test items are linked on a common scale, functional scores can be tracked across an entire episode of care as patients' functional ability changes and they move to different care settings. Users can select the format (computer-based or paper short-form) that is best suited for their clinical setting. The AM-PAC is sensitive to change in functional status and detects changes that may be missed by other outcome instruments.
What does the AM-PAC paper short-form version offer?
CREcare offers a paper short-form version of the AM-PAC for use in outpatient settings. This version assesses the basic mobility and daily activity domains and can be used to assess function of patients with different diagnoses and ability levels. Each domain consists of 15 questions, which minimizes test burden. The AM-PAC paper short-form is easily scored and scores are on the same scale that the AM-PAC computer-based version.
What are the advantages of the computer-based AM-PAC?
The computer-based AM-PAC uses computer adaptive testing (CAT) technology to select a small subset of items that are appropriate for an individual patient's functional level. This approach provides a precise estimate of a patient's functional ability by selecting a few test items, that are most appropriate for a patient's functional ability level, from the AM-PAC test item bank that cover a wide range of functional abilities. The computer-based AM-PAC provides an efficient method for collecting functional outcome data. On average, patient registration and background information data are collected in 30 seconds and it takes only 2 minutes to complete the assessment of each functional domain.
Listed below are sample questions from each of the AM-PAC domains.
Basic Mobility Sample Items: total number of items in this domain = 101
How much DIFFICULTY do you (does 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
• lifting 25 pounds (e.g., dog food or a large bag of fertilizer)
• carrying 2 plastic grocery bags with handles at your side for 50 feet
• making sharp turns when running fast
• climbing a step ladder (4-5 steps)
• doing moderately heavy house or yard work (e.g., changing a ceiling light bulb, hanging a picture on the wall, weeding a garden, or sweeping a walkway)
• taking part in strenuous activities (e.g., running 3 miles, swimming half mile, etc.)
Daily Activity sample items: total number of items in this domain = 70
How much DIFFICULTY do you (does 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
• cutting with scissors (e.g., to open a package or cut out coupons)
• getting money in and out of your wallet
• operating an ATM to get cash or make deposits
• cutting your toenails
• tying shoes
• opening medication or vitamin containers (e.g., childproof containers, small bottles) and managing individual tablets
• managing toileting aftercare, including cleaning, managing undergarments, and arranging clothes
• using a stove or hot plate to cook a meal or prepare a hot drink, including turning on or off, adjusting heat, and moving hot items around
using washer and dryer, including loading and unloading clothes, and setting the dials
Applied Cognitive: total number of items in this domain = 69
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. lesson at a place of worship, 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., a 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
What is the clinical significance of AM-PAC scores?
AM-PAC scores in each functional domain have a mean of 50 with a standard deviation of 10 and scores are distributed along a continuum of function. Below is an example of the AM-PAC functional staging chart for the basic mobility. THe chart shows how AM-PAC scores relate to mobility stages of walking within a room, walking in a building, walking outside and participating in sports.
View a larger version of the Basic Mobility Staging Chart.
View the Daily Activity Staging Chart.
The AM-PAC is ideal for tracking outcomes as a patient progresses across an episode of care. The AM-PAC can be administered as a patient self-report instrument or by clinicians or family members. The AM-PAC is currently used for internal quality improvement and benchmarking.
The AM-PAC was developed with funding from the National Institute on Disability and Rehabilitation Research and the National Institute of Health. The relevance, utility and scientific basis of the AM-PAC is supported by numerous publications in scientific journals. For a list of publications, click here. To learn more about the advantages of using item-response theory (IRT) and computerized adaptive testing (CAT) to measure rehabilitation outcomes, refer to the article by Haley and Jette (2005), Contemporary Measurement Techniques for Rehabilitation Outcome Assessment, Journal of Rehabilitation Medicine, Nov:37(6):337-45.
NOTE: CREcare offers the AM-PAC to researchers for use in IRB-approved research projects on a royalty-free basis. Customization or data management is provided on a fee-for-service basis.
Contact us to discuss how the AM-PAC and CREcare can improve your approach to measuring and monitoring rehabilitation outcomes.