Reliability of an instrument for screening hand profiles: The Practical Hand Evaluation.

STUDY DESIGN: Psychometric study with 2-week interval.

INTRODUCTION: Musculoskeletal hand complaints are common among manual workers. Mismatch between anthropometric hand features and tasks can affect the ability to perform hand activities, with an increased risk of complaints. Although screening of these features may improve diagnosis and treatment, no validated screening tool is available. The Practical Hand Evaluation (PHE) screening tool might fill this gap, but its psychometric properties are unknown.

PURPOSE OF THE STUDY: To test the reliability of the PHE and to explore the feasibility of item reduction of the PHE.

METHODS: Right-hand profiles of 117 healthy volunteers (66 women, 51 men; mean age, 22.8 years) were independently assessed 4 times by 6 couples of researchers using the PHE, twice on day 1 and twice 2-3 weeks later. Intrarater and inter-rater reliability (intraclass correlations), standard error of measurement (SEM), potential confounding factors (gender, joint hyperlaxity, and measurement order) affecting the instrument's reliability (limits of agreement), and collinearity between the PHE items were determined (variation inflation factor analysis and hierarchical clustering of correlation coefficients).

RESULTS: The intrarater and inter-rater reliabilities of the PHE were good for 12 of 14 items (86%; r = 0.67-0.90). Absolute SEM varied between 2.01 and 9.23 mm. The percentage of shifts of at least 2 classes in a repeated measurement was <15%. Cluster analysis identified 6 clusters of hand items.

DISCUSSION: The reliability for nearly all PHE items is good. Measurement errors were substantial relative to variances in the reference population, but not to gender, joint laxity and order of administration. Clustering into 6 seperated clusters of items was possible.

CONCLUSIONS: The PHE fulfills many of the criteria for screening of anthropometrics of the hand. Its reliability is high. The SEM might be improved with future adaptations toward a digital photographic PHE. Reduction to 6 items seems also possible.