Cross-cultural adaptation, reliability and validity of the Italian version of the craniofacial pain and disability inventory in patients with chronic temporomandibular joint disorders

Abstract Background To develop an Italian version of the Craniofacial Pain Disability Inventory (CFPDI-I) and investigate its psychometric abilities in patients with temporomandibular disorders (TMD). Methods The CFPDI was translated following international standards. The psychometric analyses included reliability by internal consistency (Cronbach’s alpha) and test/retest stability (intraclass correlation coefficient, ICC); construct validity was investigated by matching (a priori hypotheses) the CFPDI-I with the Italian Neck Disability Index (NDI-I), a pain intensity numerical rating scale (NRS), the Italian Pain Catastrophising Scale (PCS-I), the Italian Tampa Scale of Kinesiophobia (TSK-I), and the Italian Migraine Disability Assessment Score Questionnaire (MIDAS) (Pearson’s correlation). Alpha was set at 0.05. Results Two hundred and twelve patients with chronic TMD completed the tool. The questionnaire was internally consistent (α = 0.95) and its stability was good (ICCs = 0.91). As hypothesised, validity figures showed CFPDI-I strongly correlated with the NDI-I (r = 0.66, p < 0.05) and moderately correlated with the NRS (r = 0.48, p < 0.05), PCS (r = 0.37, p < 0.05), TSKI (r = 0.35, p < 0.05) and MIDAS (r = 0.47, p < 0.05). Similar estimates were shown by CFPDI-I subscales. Conclusions The cross-culturally adapted version of the Craniofacial Pain and Disability Inventory (CFPDI-I) showed satisfactory psychometric properties that replicate those of the original version and, therefore, can be implemented in the clinical assessment of Italian people affected by TMD.