The Neurological Hand Deformity Classification: Construct validity, test-retest, and inter-rater reliability

Simon Garbellini; Melinda Randall; Michael Steele; Catherine Elliott; Christine Imms

doi:10.1016/j.jht.2021.03.005

The Neurological Hand Deformity Classification: Construct validity, test-retest, and inter-rater reliability

J Hand Ther. 2022 Oct-Dec;35(4):581-589. doi: 10.1016/j.jht.2021.03.005. Epub 2021 Mar 29.

Authors

Simon Garbellini¹, Melinda Randall², Michael Steele³, Catherine Elliott⁴, Christine Imms⁵

Affiliations

¹ School of Allied Health, Australian Catholic University, Melbourne, VIC, Australia; Department of Pediatric Rehabilitation, Perth Children's Hospital, Perth, WA, Australia. Electronic address: simon.garbellini@health.wa.gov.au.
² Royal Children's Hospital, Melbourne, VIC, Australia.
³ Faculty of Health Sciences, Australian Catholic University, Brisbane, QLD, Australia; Nursing Research and Practice Development Centre, The Prince Charles Hospital, Brisbane, Australia.
⁴ Department of Pediatric Rehabilitation, Perth Children's Hospital, Perth, WA, Australia; School of Occupational Therapy and Social Work, Curtin University, Perth, WA, Australia.
⁵ Department of Pediatrics, The University of Melbourne, Melbourne, VIC, Australia.

PMID: 34011469
DOI: 10.1016/j.jht.2021.03.005

Abstract

Background: The Neurological Hand Deformity Classification (NHDC) is an impairment-based tool that classifies hand deformity into one of two ordinal scales: flexion or extension deformities. Classification is made from live observation or from recorded video footage. Differentiation between the levels is determined by wrist position and wrist and finger movement.

Purpose: To examine aspects of validity and reliability of the NHDC.

Study design: A measurement study design.

Methods: Data from a convenience sample of 127 children with cerebral palsy, 66 males: 61 females, ranging in age from 8 months to 15 years, across all Manual Ability Classification System levels I to V, were analyzed. Construct validity was assessed by testing predetermined hypotheses of relationships between the NHDC and measures of body function and activity measures with observed performance using the Chi Squared Test of Independence and Spearman Correlation Coefficient. Test-retest and inter-rater reliability were assessed by calculating agreement between repeated measures and paired raters using weighted kappa and Cohen's kappa with 95% confidence intervals.

Results: Predicted hypotheses for the NHDC were met in nine of 10 Spearman's rho correlations with body structure measures and in 2 of 7 correlations with activity measures. Test-retest for flexion deformities: κw = 0.84; 95% CI 0.70-0.98; and extension deformities: κ = 1.0; 95% CI 1.0-1.0 was good to excellent; inter-rater reliability for flexion deformities: κw = 0.76; 95% CI 0.67-0.85; and extension deformities κ = 0.75; 95% CI 0.43-1.0 was moderate to excellent.

Conclusion: Expected relationships between the NHDC and other measures, stability between repeated measures and acceptable between-rater agreement supports confidence classifying hand deformity in children with cerebral palsy with the NHDC.

Keywords: Cerebral palsy; Classification; Hand deformities; Psychometrics.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cerebral Palsy* / diagnosis
Child
Female
Fingers
Hand Deformities*
Humans
Male
Reproducibility of Results
Upper Extremity