Translating the Research Diagnostic Criteria for Temporomandibular Disorders into Malay: evaluation of content and process.
OBJECTIVE
To develop a Malay-language version of the Axis II Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) through a formal translation/back-translation process and to summarize available data about the psychometric properties of the translated scales.


METHODS
To cross-culturally adapt the instrument, the RDC/TMD underwent translation using a forward-backward method. Subjects were recruited to test the congruency between translated and original versions of the RDC/TMD. The psychometric properties of 3 domains (Graded Chronic Pain Scale, Nonspecific Physical Symptoms, and Depression) of the RDC/TMD were examined, and the literature on this topic was reviewed.


RESULTS
All the items scored 93% to 100% congruency. Cronbach's alphas for Graded Chronic Pain Scale, Nonspecific Physical Symptoms, and Depression were 0.77, 0.71, and 0.88, respectively (n = 40). The test-retest reliability of scores (intraclass correlation coefficient [ICC]) and levels (Spearman's rho) for these domains showed ICCs of 0.97, 0.94, and 0.95, respectively, with a lowest ICC value of 0.84 (n = 40); the Spearman's rho values were 0.93, 0.74, and 0.74, respectively. The discriminant validity between patients with pain symptoms (n = 40) and normal pain-free controls (n = 40) were statistically significant (P < .001). These correlations provide support for the internal consistency and validity of the Graded Chronic Pain Scale, Nonspecific Physical Symptoms, and Depression domains of the translated version of the RDC/TMD, which were found to be comparable to the psychometric properties of the original and other international translated versions.


CONCLUSIONS
The cross-cultural adaptation of the RDC/TMD into the Malay language is suitable for use in Malaysia.
Khoo
Suan-Phaik
SP
Department of Oral Pathology, Oral Medicine & Periodontology, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia. suanphaik@gmail.com
Yap
Adrian U Jin
AU
Chan
Yiong Huak
YH
Bulgiba
Awang M
AM
D016022:Case-Control Studies; D003431:Cross-Cultural Comparison; D003863:Depression / Q000175:diagnosis; D005157:Facial Pain / Q000175:diagnosis; D006801:Humans; D008296:Malaysia; D010554:Personality Disorders / Q000175:diagnosis; D011594:Psychometrics; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D013705:Temporomandibular Joint Disorders / Q000175:diagnosis*; D014177:Translations