RESUMO
OBJECTIVE: To verify whether the Fonseca Anamnestic Index (FAI) has adequate sensitivity and specificity to be used in the diagnosis of temporomandibular disorder (TMD). METHODS: Two hundred-sixty-five participants with symptoms of TMDs were assessed through the FAI and through the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and then classified as sick or non-sick. The sensitivity, specificity, and predictive values of the FAI in relation to the RDC/TMD were calculated using the STATA 14.0 software. RESULTS: Most of the patients were female, white, without a steady job, and the average age was 37.57 years. The FAI showed high sensitivity (97.21%) but obtained a low specificity (26.00%). The positive and negative predictive values were 84.96% and 68.42%, respectively. CONCLUSION: The FAI is very sensitive in identifying patients who actually have TMD but not very specific in identifying non-TMD patients, being indicated only for initial screening of patients.