Validity and reliability of the Functional Dexterity Test in children

Abstract

Study design: Clinical measurement study.

Introduction: The Functional Dexterity Test (FDT) has not been validated in children.

Purpose of the study: To determine reliability and validity of the FDT in a pediatric population.

Methods: Intraclass Correlation Coefficients (ICCs) were used to calculate interrater and test-retest reliability in typically developing children. Pearson correlation coefficients were used to compare FDT speed with the Jebsen-Taylor Hand Function Test (JHFT) and with 2 activities of daily living tasks to establish validity in children with congenital hand differences.

Results: The FDT demonstrated excellent interrater (ICC, 0.99) and test-retest (ICC, 0.90) reliability. Pearson correlation coefficients exceeded 0.67 for JHFT subsets of fine dexterity and were all less than 0.66 for JHFT subsets of gross grasp. Correlations with the activities of daily living tasks were good to excellent. FDT speeds in TD children exceeded those of children with congenital hand differences (P < .001), demonstrating discriminant validity.

Discussion: Children with congenital hand differences are often treated early in life, making it important to reliably assess hand function of these young children to distinguish developmental change from changes due to interventions. The FDT can reliably measure functional progress over time, help clinicians monitor the efficacy of treatment, and provide families realistic feedback on their child's progress.

Conclusion: The FDT is a valid and reliable instrument for the measurement of fine motor dexterity in children.

Keywords: Dexterity; Functional Dexterity Test; In-hand manipulation; Pediatric; Reliability; Validity.