Reliability and Validity of the Malaysian English Version of the Diagnostic Criteria for Temporomandibular Disorder (M‐English DC/TMD)

Abstract

This study aimed to assess the reliability and validity of Graded Chronic Pain Scale 2.0 (GCPS 2.0) and Jaw Functional Limitation Scale‐20 (JFLS‐20) of the Malaysian English version of Diagnostic Criteria for Temporomandibular Disorders (M‐English DC/TMD). GCPS 2.0 and JFLS‐ 20 underwent psychometric analysis involving content, face, criterion, and construct (exploratory factor analysis (EFA), convergent, discriminant, known group) validity including internal and testretest reliability on 208 samples. The construct validity was assessed against 14 hypotheses and nonparametric statistics were used to assess the data. The GCPS 2.0 and JFLS‐20 had high internal consistencies (α = 0.85 and 0.96) with an intraclass correlation coefficient value of 0.95 and 0.97, respectively. The content validity index for GCPS 2.0 and JFLS‐20 were 0.87 and 0.95, respectively. The EFA of GCPS 2.0 identified one factor whereas three factors were identified for JFLS‐20. Both instruments had moderate to strong positive correlation with other instruments when assessing for concurrent (r = 0.75–0.80, p < 0.01) and convergent (r = 0.58–0.70, p < 0.01) validity, while moderate to high negative correlation (r = −0.86–−0.68, p < 0.01) against the global self‐rating oral health items. Based on the study, GCPS 2.0 and JFLS‐20 of the M‐English DC/TMD proven to be reliable and valid for use in the Malaysian population with TMD.