Arm Motor Ability Test

Original Editor - Redisha Jakibanjar Top Contributors - Redisha Jakibanjar, Kim Jackson and Candace Goh

Objective[edit | edit source]

  • Assess the functional capacity of the upper extremity in Activities of Daily Living (ADL) using both qualitative and quantitative method [1]
  • Was developed in 1988 by McCulloch to supplement the Wolf Motor Function Test (WMFT) as it was unable to detect the improvements in ADL activities of people with stroke receiving constraint-induced movement therapy.[2] The Arm Motor Ability Test (AMAT) focuses mainly on activity limitation rather than impairment. [3]

Intended Population[edit | edit source]

Method of Use[edit | edit source]

The Arm Motor Ability Test (AMAT) has different versions and the components vary accordingly. Originally, AMAT consisted of 17 components. The AMAT version 13 has 13 components, the AMAT version 10 has 10 components, and the AMAT version 9 consists of 9 components.[2][5]The tasks in the tool are further divided into 1-3 subtasks or movements and the tasks may involve different contributions from the bilateral arm or distal and proximal part of the affected arm.[5]

Although the subtasks are timed individually, the patient is allowed to perform the task continuously and fluently. The time limit for each task is usually 1-2 minutes.[5] The task is evaluated in two scales: the Functional Ability scale (ability to perform the task) and the Quality of Movement (how the task is performed). [2][5] Each component is scored on 6 points Likert scale from 0 (no hand use) to 5(normal hand use). The Functional Ability: 0 = no use, 1 = very slight use, 2 = slight use,3 = moderate use, 4 = almost normal use, 5 = normal use and the Quality of Movement: 0 = no use, 1 = very poor, 2 = poor, 3= fair, 4 = almost normal, 5 = normal. [5]The more score means the fewer activity limitations and the less score means more activity limitations. [2][5]

The examiner/evaluator should read the instructions for each task carefully and the task is demonstrated to the patient three times using same arm/arms as the patient would use. The patient is not allowed to practice the task from both affected and unaffected arms because of the possibility of inter manual transfer of motor learning effects. If a subject could not complete a task component within the given time limit(1-2 minutes), the time limit is arbitrarily assigned as the score and timing of the remaining task components are resumed. The median is taken for all the time taken while performing and the mean for Functional Ability and Quality of Movement.[5][2]

The equipment needed to perform tasks are:

  • Silverware and plate
  • Play-doh
  • Mug
  • Comb
  • Foam sandwich
  • Towel
  • Jar
  • 2 shirts (different styles)
  • Light switch
  • Door
  • Dried beans
  • Shoe and Shoelaces
  • Telephone

Evidence[edit | edit source]

Minimal Detectable Change (MDC):[edit | edit source]

The minimal detectable change in AMAT based on therapists' perception of change (Global Rating of Change (GROC)=5)[6]

  • Grasp: 0.44
  • Release: 0.42
  • Ability to move affected arm and hand: 0.42
  • Ability to perform Canadian Occupational Performance Measure activity: 0.42
  • Overall arm and hand function: 0.42

The minimal detectable change in AMAT based on participants' perception of change (GROC=5)[6]

  • Grasp: 0.44
  • Release: 0.42
  • Ability to move affected arm and hand: 0.40
  • Ability to perform Canadian Occupational Performance Measure activity: 0.40
  • Overall arm and hand function: 0.40

Minimally Clinically Important Difference (MCID):[edit | edit source]

The Minimally Clinically Important Difference in AMAT based on therapists' perception of change (GROC=5)[6]

  • Grasp:0.34
  • Release: 0.42
  • Ability to move affected arm and hand: 0.40
  • Ability to perform Canadian Occupational Performance Measure activity: 0.35
  • Overall arm and hand function: 0.42

The minimal detectable change in AMAT based on participants' perception of change (GROC=5)[6]

  • Grasp: 0.29
  • Release: 0.31
  • Ability to move affected arm and hand: 0.29
  • Ability to perform Canadian Occupational Performance Measure activity: 0.30
  • Overall arm and hand function: 0.40

Reliability[edit | edit source]

Test/retest reliability[edit | edit source]

- Excellent( ICC=0.93-0.99)[5]

Interrater/Intrarater reliability[edit | edit source]

- Excellent (ICC=0.95-0.99)[5]

Internal consistency[edit | edit source]

- Excellent with Cronbach's alpha 0.93[3]

- Excellent with inclusion of extreme scores using Pearson Separation Index (0.86)[3]

- Excellent with exclusion of extreme scores using Pearson Separation Index (0.88)[3]

Validity[edit | edit source]

Concurrent Validity[edit | edit source]

- Adequate to excellent with Motricity Index Arm (correlation coefficent=0.45-0.61)[5]

- Excellent with Fugl Meyer Assessment (correlation coefficient= 0.92-0.94)[1]

Construct Validity[edit | edit source]

- Excellent Correlation with Wolf Motor Function Test (WMFT), Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT) (0.78-0.79)[3]

- Excellent Correlation with FMA wrist/hand sub-score (0.74) [3]

- Excellent Correlation with FMA shoulder/elbow sub-score (0.66) [3]

- Adequate Correlation with Stroke Impact Scale (SIS) hand sub-score (0.40)[3]

- Poor Correlation with SIS communication sub-score (-0.16)[3]

Content Validity[edit | edit source]

-Consistencies between the AMAT-9 and the Rash model expectations [3]

Floor/ceiling effect[edit | edit source]

-The AMAT time of performance exhibited significant ceiling and floor effects with respect to FMA[1]

Responsiveness[edit | edit source]

Sensitivity in AMAT based on Therapists' perception of change [6]

  • Grasp: 0.64
  • Release: 0.60
  • Ability to move affected arm and hand: 0.58
  • Ability to perform COPM tasks: 0.62
  • Overall arm and hand function: 0.62

Sensitivity in AMAT based on Participants' perception of change [6]

  • Grasp: 0.67
  • Release: 0.64
  • Ability to move affected arm and hand: 0.53
  • Ability to perform COPM tasks:0.56
  • Overall arm and hand function: 0.50

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 Chae J, Labatia I, Yang G. Upper limb motor function in hemiparesis: concurrent validity of the Arm Motor Ability test. American journal of physical medicine & rehabilitation. 2003 Jan 1;82(1):1-8.
  2. 2.0 2.1 2.2 2.3 2.4 Scale Library. Finding a clinical assessment scale-Physical medicine and rehabilitation.Arm Motor Ability Test. accessed on 2021/3/19. Available from:http://scale-library.com/assessment_scale_result.php?echelle=Wolf%20Motor%20Function%20Test%20(WMFT)&theme=&type=&scalage=adulte&retour=liste&cle=&echelle_box=Arm%20Motor%20Ability%20Test%20(AMAT)
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 O'Dell MW, Kim G, Rivera L, Fieo R, Christos P, Polistena C, Fitzgerald K, Gorga D. A psychometric evaluation of the Arm Motor Ability Test. Journal of rehabilitation medicine. 2013 Jun 5;45(6):519-27.
  4. 4.0 4.1 Shirley Ryan Ability lab.Rehabilitation measures database.Arm Motor Ability Test.Accessed on 2021/03/13.Available from:https://www.sralab.org/rehabilitation-measures/arm-motor-ability-test
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 Kopp B, Kunkel A, Flor H, Platz T, Rose U, Mauritz KH, Gresser K, McCulloch KL, Taub E. The Arm Motor Ability Test: reliability, validity, and sensitivity to change of an instrument for assessing disabilities in activities of daily living. Archives of physical medicine and rehabilitation. 1997 Jun 1;78(6):615-20.
  6. 6.0 6.1 6.2 6.3 6.4 6.5 Fulk G, Martin R, Page SJ. Clinically important difference of the arm motor ability test in Stroke survivors. Neurorehabilitation and neural repair. 2017 Mar;31(3):272-9.