Assessment Overview

Purpose: The Activities Specific Balance Confidence Scale (ABC) is a self-report measure assessing a person’s confidence in their ability to balance. The individual rates himself/herself from 0% (no confidence) to 100% (completely confident) on their ability to perform various balance activities: walk around the house, bend over to pick up an object, stand on tip-toes, get in a car, walk up or down a ramp, stand on a chair, etc. There are 16 items on this scale.

Equipment: None

ICF Category: Activity, Participation

Assessment Handout

Assessment Psychometrics

Stroke

The ABC is not recommended for use in patients with acute stroke but is recommended for patients with subacute and chronic stroke and is not recommended for use in acute care, but is recommended for inpatient rehabilitation, skilled nursing facilities, outpatient rehabilitation, and home health. Students should not learn to administer the ABC but should be exposed to it and it is appropriate for use in research. Below are psychometrics for the ABC when assessed in a CVA population:

• Concurrent Validity: Not examined in the stroke population

• Construct Validity: Chronic Stroke adequate correlation with BBS (r=0.36), Chronic Stroke adequate correlation with gait speed (r=0.48)

• Content Validity: Items were ranked as perceived low risk activities and perceived high risk activities

• Cutoff Score: 81.1 provides relative certainty that individual did not have a history of multiple falls

• Floor/Ceiling Effects: No floor or ceiling effects found for total score but some floor effects noted in 3 individual items and some ceiling effects noted in 8 individual items

• Mean Data: Total score = 68.3 (ICC=0.85)

• SEM: 5.05

• Test-retest: Chronic Stroke Excellent 4=week total reliability (ICC=0.85)⁴¹, Chronic Stroke Adequate to excellent item reliability (ICC=0.53-0.93)

Multiple Sclerosis

Neuro PT EDGE² recommends (¾) the use of the ABC in all practice settings. There is still a lack of responsiveness data in MS. It is also recommended (¾) for individuals with an EDSS level <7.5. It is not recommended (¼) for those with an EDSS of 8.0-9.5. Students should learn how to administer this tool and it has been validated in research.

The minimal data that has been collected for the psychometrics between the ABC and MS are presented in the list below. While there is not much evidence at this time, the ABC is a core outcome measure that has been supported for use in all adults with a neurologic condition. More research should still be conducted on a mean score, MDC, reliability, and MCID for this population when using the ABC.

• Concurrent Validity: Related to BBS (r=0.48), DGI (r=0.54), TUG (r=-0.38), Hauser Deambulation Index (r=-0.45). Tested in a group of 51 people with MS.

• Cutoff Score: In 51 patients with MS, a cut off score of >40% demonstrated sensitivity of 65% and specificity of 77% between fallers and non-fallers.

• Test-retest Reliability: ICC= 0.92 in 25 individuals with MS¹⁶

Parkinson's Disease

The ABC scale is recommended for use with PD patients in Hoehn and Yahr stages I-III, but not recommended in Hoehn and Yahr stage V. There is not yet enough evidence to recommend the use of the ABC scale with patients in Hoehn and Yahr stage IV. Students do not need to learn or be exposed to the ABC scale for the PD population. The ABC scale is appropriate for use in intervention research studies.

• Construct Validity: Fallers have lower ABC scores²¹ ; Scores >80 have a significant association with lower fall risk; Scores distinguish between HY stage 1 and 3

• Criterion Validity: Adequate correlation with knee muscle strength (r=0.301); Excellent inverse correlation with UPDRS-Posture and Gait score (r=-0.661)

• Cutoff Score: 69% - Predictive of recurrent falls

• Mean Data: 73.6%

• MDC: 11.12- 13

• SEM: 4.01

• Test-retest: Excellent (ICC=0.79 - 0.96)

Spinal Cord Injury

Neuro PT EDGE states that the ABC is reasonable to use in patients with acute, subacute, and chronic SCI patients because there are no studies relating specifically to SCI. The ABC is not recommended for AIS A and B individuals, and is only reasonable to use for AIS C and D individuals for the above reason. Students should not specifically learn to administer this test for the SCI population because of the missing data. Also, more validation must be done before this test will be recommended for use in research.

A study done in 2017 looking at the psychometrics of the ABC and incomplete motor SCI found that the ABC is a valid and reliable test when measuring assessing balance confidence in individuals with chronic SCI. The authors found a high test-retest reliability among participants (ICC=0.93). The MDC was found to be 14.78% and showed convergent validity with the following tests: miniBESTest, isometric strength of lower extremity muscle groups, 10MWT, SCI-FAP, and WISCI II.

Traumatic Brain Injury

There is not yet evidence to suggest the use of the ABC scale with patients after a brain injury who are completely independent or mildly dependent, but it is not recommended with those who are moderately or severely dependent. The ABC scale has limited studies on use in acute care, skilled nursing facilities, inpatient rehabilitation, outpatient rehabilitation, and home health. Students should be exposed to this measure but do not need to learn to administer it. The ABC scale is appropriate for use in research. Below are psychometrics for the ABC when assessed in a TBI population.

• Construct Validity: Excellent correlation with Community Balance and Mobility Scale (r=0.60)