Adult norms for the Corbett Targeted Coin Test

Clinical measurement INTRODUCTION: Dexterity is important for daily activities. The Corbett Targeted Coin Test (CTCT) measures dexterity with palm-to-finger translation and proprioceptive target placement, but lacks established norms.

To establish norms for the CTCT with healthy adult subjects.

The inclusion criteria consisted of participants that were community dwelling, non-institutionalized, able to make a fist with both hands, perform finger-to-palm translation of twenty coins, and be at least 18 years of age. CTCT standardized testing procedures were followed. Quality of performance (QoP) scores were determined by speed in seconds and number of coin drops (each a 5-second penalty). QoP was summarized within each age, gender and hand dominance subgroup using the mean, median, minimum, and maximum. Correlation coefficients were computed for relationships between age and QoP, and between handspan and QoP.

Of the 207 individuals who participated, 131 were females and 76 males with an age range of 18-86 and mean age of 37.16. Individual QoP scores ranged from 13.8 to 105.3 seconds, with median scores ranging from 28.7 to 53.3 seconds. The mean for males was 37.5 seconds for the dominant hand (range 15.7-105.3) and 42.3 seconds (range 17.9.-86.8) for the non-dominant hand. The mean for females was 34.7 seconds for the dominant hand (range 14.8-67.0) and 38.6 seconds (range 13.8.-82.7) for the non-dominant hand. Lower QoP scores indicate a faster and/or more accurate dexterity performance. Females showed better median QoP for most age groups. The best median QoP scores were seen in the 30-39 and 40-49 age ranges.

Our study agrees to some extent with other research that reported dexterity decreases with age, and increases with smaller hand spans.

Normative data for the CTCT can be a guide for clinicians evaluating and monitoring patient dexterity with palm-to-finger translation and proprioceptive target placement.