Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) - The Polish version of a dual-axis system for the diagnosis of TMD. RDC/TMD form

Aim of the study: To describe steps taken to conduct a formal forward translation/back-translation from English to Polish, and to establish the cultural equivalence of the Polish version of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). This will be preceded by a brief historic overview of the insights into TMD, so as to provide a rationale for using this dual-axis diagnostic system. Methods: The Clinical Examination Form, the Specifications section, and the algorithms for axis I and II scoring of the RDC/TMD document were forward translated from English to Polish. In order to cross-culturally adapt the instrument, the History Questionnaire and the verbal directions for the patient (part of the Specifications section) were both forward translated and back-translated. Special attention was given to the questions from the History Questionnaire focusing on demographic characteristics. To that end, the official Translation Guidelines of the International RDC/TMD Consortium were followed. Results: No substantial difficulties in translating were encountered during either the forward translation process of the Clinical Examination Form, the Specifications section, and the algorithms, or during the forward and backtranslation of the History Questionnaire and the verbal directives for the patient. Thus, a linguistically valid and culturally equivalent Polish translation resulted. Conclusions: Since the internationally established and accepted translation/adaptation Guidelines were used to establish the Polish version of RDC/TMD, this instrument is now available for the assessment of TMD in Poland.