Action Research Arm Test (ARAT)

Contributors

Brittany Carlton, Marina Petrevska & Julietta Zsofynak

Objective

The Action Research Arm Test (ARAT) is a 19 item observational measure used by physical therapists and other health care professionals to assess upper extremity performance (coordination, dexterity and functioning) in stroke recovery, brain injury and multiple sclerosis populations. The ARAT was originally described by Lyle in 1981 as a modified version of the Upper Extremity Function Test and was used to examine upper limb functional recovery post damage to the cortex (Yozbatiran, Der-Yeghiaian & Cramer, 2008).

Items comprising the ARAT are categorized into four subscales (grasp, grip, pinch and gross movement) and arranged in order of decreasing difficulty, with the most difficult task examined first, followed by the least difficult task. Lyle proposed that this hierarchical ordering would improve efficiency of testing, as normal movement on the most difficult items would be indicative of successful performance on proceeding items (Yozbatiran, Der-Yeghiaian & Cramer, 2008). Task performance is rated on a 4-point scale, ranging from 0 (no movement possible) to 3 (movement performed normally).

Intended Population

The ARAT has been standardized for individuals with stroke, brain injury, Multiple Sclerosis, and Parkinson’s Disease. The test can be administered to individuals 13 years of age and older (Ability Lab, 2016).

Method of Use

Required Equipment

The following materials (Figure 1) are required for testing (Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, 2018):

• Chair without armrests
• Table
• Wooden blocks of various sizes
• Cricket ball
• Sharpening stone
• Alloy tubes
• Washer and bolt
• 2 glasses
• Sharpening stone
• Marbles
• Ball bearings
• Tin lid

Figure 1: ARAT Kit (Rehab Solutions, 2014).

Positioning

Standard positioning for the ARAT has the subject seated upright in a chair with a firm back and no armrests. The head should be in a neutral position, with feet in contact with the floor. This body posture must be maintained throughout the testing period, with the trunk contacting the back of the chair. Feedback is provided, as required, to prevent the subject from standing up, shifting laterally or leaning forward (Yozbatiran, Der-Yeghiaian & Cramer, 2008).

Figure 2: ARAT Positioning

Instructions

To ensure that test items are performed unilaterally and that the non-test hand remains visible throughout the assessment, the subject is instructed to begin with both forearms pronated and hands resting on the table. Exceptions to this rule are for tasks within the gross movement category which require that the subject begins with bilateral forearm pronation and hands resting on the lap (Yozbatiran, Der-Yeghiaian & Cramer, 2008).

The administrator then provides instructions to the subject to perform tasks within the grasp, grip, pinch and gross movement subscales, while scoring the individual based on their performance of each task. The administrator follows instructions provided on the scoring sheet when instructing the subject about the required task.

For grasp tasks, the subject is instructed to lift testing materials from the surface of the table to a shelf located 37 cm above the starting point. For grip related tasks, the individual grips testing materials and moves them from one side of the table to the other. Pinching tasks require the client to perform similar movements to those in the grip subscale, but with the use of a fine motor pincer grip instead. Gross movement tasks require the individual to move their testing arm to different resting positions including on top of their head, behind their head or to their mouth (Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, 2018).

Scoring & Interpretation

The 19 items comprising the ARAT are scored using a 4 point ordinal scale, as follows:

0 = no movement

1= movement task is partially performed

2 = movement task is completed but takes abnormally long

3 = movement is performed normally

As outlined by Lyle:

Subjects are first asked to perform the most difficult task within a subscale. If a subject performs the task adequately with normal movement, they are scored a 3 on this item and all remaining items within a subscale. A score between 0-2 on the first item suggests that the second task (least difficult) must be evaluated. Subjects scoring 0 on the second task item are unlikely to be successful on subsequent scale items and are scored 0 for remaining tasks within a category. Remaining moderate level tasks within a subscale are thus not evaluated. Otherwise, all test items within a category must be performed. Consequently, subjects may be asked to perform anywhere from 4 tasks to 19 tasks depending on their performance (Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, 2018).

The maximum score on the ARAT is 57 points, with the lowest score 0 points (Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, 2018). There are no cut off scores as this assessment is continuous and based on a subject's observed mobility.

Figure 3: ARAT Scoring Sheet (Internet Stroke Center, 2018).

Figure 4: ARAT subscale scoring (Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, 2018).

Evidence

Reliability

The ARAT has been shown to have strong psychometric properties. Many domains of reliability have been tested for the ARAT, with studies unanimously showing high reliability, including test-retest reliability ranging from 0.965-0.968 and inter-rater reliability ranging from 0.996-0.998 (Ability Lab, 2016; McDonnell, 2008). The reliability of ARAT use in the Parkinson's Disease patient population has also been thoroughly tested. The test-retest reliability was found to be 0.99 with a grip reliability of 0.93, and a gross movement reliability of 0.99 (Song, 2012).

Validity

The ARAT has proven to have strong validity when compared with other upper extremity function scales. Concurrent validity was shown to be high for the ARAT when the assessment was compared with the upper extremity component of the Fugl-Meyer Assessment (FMA) and the Motor Assessment Scale (MAS) (McDonnell, 2008). In a comparative study, the results of the ARAT in stroke populations were compared with scores on the Wolf Motor Function Test, Motor Activity Log, and the Stroke Impact Scale. The results showed good to moderate correlations between the results, indicating a good predictive validity (Chen, 2012).

Responsiveness

The ARAT has high responsiveness with this assessment tool having great ability to detect clinically significant changes in an individual's upper arm motor ability, especially in the stroke population (McDonnell, 2008).

Limitations

While the ARAT has many strengths, it is also plagued by limitations that can be improved upon in the future to render the tool more trustworthy and applicable to a larger population. One limitation of the ARAT is that scoring is subjective and based on the administrators’ interpretation of the client's ability to do the task, with details of test item positioning and maximum time allocated for each item omitted and open to interpretation (Carpinella, Cattaneo & Ferrarin, 2014 & McDonnell, 2008). Scoring may also be impacted by lack of specification of the amount of time defining "abnormally long," used to differentiate a score of 2 or score of 3. Lack of standardization regarding the weight, size and source of testing materials may also result in variability in scoring (Yozbatiran, Der-Yeghiaian & Cramer, 2008).

Also, while the ARAT is known for accurately measuring moderate to high degrees of motor impairments, it has shown to have poor sensitivity for measuring mild impairments (Carpinella et al., 2014). Factors that decrease the comprehension of the instructions, such as cognitive impairment or Wernicke’s aphasia, might also affect the quality of the results.

References

Ability Lab. (2016). Action research Arm Test. Retrieved on May 1st, 2018 from https://www.sralab.org/rehabilitation-measures/action-research-arm-test

Carpinella, I., Cattaneo D., & Ferrarin, M. (2014). Quantitative assessment of upper motor function in Multiple Sclerosis using an instrumented Action Research Arm Test. Journal of Neuroengineering and Rehabilitation, Vol 11:67

Chen, H.F., Lin K.C., Wu, C.Y., & Chen, C.L. (2012). Rasch validation and predictive validity of the action research arm test in patients receiving stroke rehabilitation. Arch Phys Med Rehabil, Vol 93(6), pp. 1039-1045

Heart and Stroke Foundation Canadian Partnership for Stroke Recovery. (2018). Action Research Research Arm Test (ARAT). Retrieved on May 1st, 2018 fromhttps://www.strokengine.ca/en/quick/arat_quick/

Internet Stroke Center. (2018). Action Research Arm Test. Retrieved on May 1st, 2018 from http://www.strokecenter.org/wp-content/uploads/2011/08/action_research_arm_test.pdf

Lyle, R. C. (1981). A performance test for assessment of upper limb function in physical rehabilitation treatment and research. International Journal of Rehabilitation Research, 4(4), 483-492. doi:10.1097/00004356-198112000-00001

McDonnell, M. (2008). Action Research Arm Test. Australian Journal of Physiotherapy, 54. Retrieved on May 1st, 2018 from https://pdfs.semanticscholar.org/313b/7c9e2b59cbd2efc41a225d03600906b50764.pdf

Rehab Solutions, (2014). ARAT Kits. Retrieved on May 1st, 2018 from http://www.aratkits.com/about/

Song, CS. (2012). Intrarater Reliability of the Action Research Arm Test for Individuals with Parkinson’s Disease. J. Phys. Ther. Sci. Vol 24: pp. 1355-1357.

Yozbatiran, N., Der-Yeghiaian, L., & Cramer, S. C. (2008). A standardized approach to performing the action research arm test. Neurorehabilitation and Neural Repair, 22(1), 78-90. doi:10.1177/1545968307305353