A Digital Box and Block Test for Hand Dexterity Measurement: Instrument Validation Study

Area of Science:

• Rehabilitation Science
• Biomedical Engineering
• Clinical Assessment Tools

Background:

• The Box and Block Test (BBT) is a standard clinical tool for assessing unilateral gross manual dexterity.
• It is widely applied across diverse patient populations, including elderly individuals and those with neurological conditions.
• Current BBT administration relies on manual timing and scoring, introducing potential variability.

Purpose of the Study:

• To introduce and evaluate a newly developed digitized version of the BBT, termed the digital BBT (dBBT).
• To determine the concurrent validity, test-retest reliability, and interrater reliability of the dBBT.
• To assess the dBBT's accuracy and practicality compared to the traditional BBT.

Main Methods:

• Twenty-nine healthy participants completed both the conventional BBT and the dBBT at the initial assessment.
• The dBBT was re-administered to assess test-retest reliability within a 10-day interval.
• Concurrent validity was evaluated using correlation and Bland-Altman analysis; reliability was assessed via Intraclass Correlation Coefficients (ICC).

Main Results:

• The dBBT demonstrated moderate concurrent validity with the conventional BBT (r=0.48, P=.008).
• Test-retest reliability was moderate (ICC=0.72), with a standard error of measurement of 3.1 blocks.
• Interrater reliability was also moderate (ICC=0.67, P=.02), and Bland-Altman analysis confirmed sufficient accuracy.

Conclusions:

• The digital BBT (dBBT) provides an objective and automated method for measuring gross hand dexterity.
• The dBBT retains the essential characteristics of the original test while enhancing measurement precision.
• Its simple implementation makes the dBBT a valuable tool for clinical and research settings.