Translation and Validation of Rating-of-Fatigue Scale to be Used in Nonsurgical Endodontic Re-treatment

BACKGROUND: This study aimed to translate and validate the rating-of-fatigue (ROF) scale in the Kannada language.

METHODS: This current study involved two steps, where forward translation, backward translation, cross-cultural adaptation, and test of a pre-final version of the ROF scale were conducted in the first step. Content validity, face validity, and construct validity of the ROF scale were performed in five stages. This study enlisted the help of eight experts to create the ROF scale in the Kannada language. Moreover, 50 patients participated by responding to a variety of Likert scale and numeric scale questionnaires that surveyed the intention of measuring the ROF scale. The content validity and face validity were assessed by using the index prepared for the content validity and face validity, respectively, along with mean and standard deviation (SD). The correlation between the Kannada version of the ROF measure and a numerical rating scale-facial rating scale (NRS-FRS) was assessed by the Pearson's correlation coefficient (PCC). Moreover, a comparison of the mean value of ROF and NRS-FRS was performed by the paired t-test.

RESULTS: The Kannada version of the ROF scale was prepared after getting consensus from all the experts. The fatigue questionnaire met a high level of expert content validity (0.93) and showed that most experts opined high relevance (1.00) for measuring dental fatigue. The fatigue questionnaire meets a high level of response in face validity (0.92) based on the face validity indices. PCC showed a high level of construct validity (r = 0.819) of the ROF scale. No significant difference (P = 0.858) was observed between ROF and NRS-FRS by the paired t-test.

CONCLUSION: The Kannada version of the ROF scale is a valid tool to assess dental fatigue.