Measuring Hand Dexterity in People With Parkinson's Disease: Reliability of Pegboard Tests.

IMPORTANCE

Knowledge regarding the reliability of pegboard tests when used to measure dexterity in people with Parkinson's disease (PD) is currently limited.

OBJECTIVE

To examine the test-retest and interrater reliability of the 9-Hole Peg Test (9HPT) and Purdue Pegboard Test (PPT) in people with PD.

DESIGN

Cross-sectional observational study. For test-retest reliability, tests were completed on 2 days, 1 wk apart, in the "on" phase and "end-of-dose" period of participants' medication cycle. For interrater reliability, occupational therapists and physical therapists rated prerecorded pegboard test performance of participants with PD.

SETTING

Test-retest reliability was determined in participants' homes or in a university department. Interrater reliability was determined in a university department or a hospital setting.

PARTICIPANTS

Test-retest reliability was determined with volunteers diagnosed with PD (N = 30). Interrater reliability was determined with a convenience sample of occupational and physical therapists (N = 11).

OUTCOMES AND MEASURES

The 9HPT and PPT are commonly used measures of manual dexterity.

RESULTS

PPT subtests showed higher test-retest reliability (intraclass correlation coefficients [ICCs] ≥ .90) in both phases of the medication cycle compared with the 9HPT (ICCs = .70-.81). Minimal detectable change scores indicated acceptable measurement error for both tools. Interrater reliability for recorded performance of each measure was very good (ICCs > .99), with no calculable measurement error.

CONCLUSIONS AND RELEVANCE

Although both tools showed adequate test-retest and interrater reliability, results suggest that the PPT may be a more reliable measure of dexterity loss in people with PD.

WHAT THIS ARTICLE ADDS

This study informs the clinical measurement of the loss of manual dexterity in people with PD, a frequent problem reported by people living with this disorder.