Cross-validation and initial investigation of two abbreviated methods of the finger tapping test

The Finger Tapping Test (FTT) is a widely utilized measure to assess lateralized motor speed and dexterity. The current study sought to cross-validate an abbreviated version of the FTT (i.e., M of Trials 3-5) and to evaluate a novel abbreviated method (i.e., M of three trials within five taps of each other; "3 within 5") to examine their respective effectiveness as a predictor of full-score performance based on a traditional administration procedure. The results showed that the abbreviated methods accurately predicted the full-test score, and any statistically significant differences that emerged were small based on effect size analysis and unlikely to be clinically meaningful. These findings were consistent across genders, among older adults, and among individuals displaying significant inter-trial tapping variability and thus requiring lengthier administration time. Classification accuracy statistics for the detection of impairment and performance validity status were high for both abbreviated methods. The results support two valid options for shortening the duration of the FTT. Both methods, used independently or in combination, are compatible with traditional administration procedures.