Polish language adaptation and validation of the Fonseca Anamnestic Index for individuals with temporomandibular disorders

Background. Given the notable prevalence of temporomandibular disorders (TMD) in the Polish population, there is a clear need for the use of simple, reliable questionnaires as screening tools to facilitate the referral of patients to TMD specialists. Objectives. The aim of the study was to translate and adapt the Fonseca Anamnestic Index (FAI) into Polish and assess its reliability and validity in identifying TMD symptoms. Material and methods. The Polish adaptation of the FAI (FAI-PL) was developed in accordance with the international guidelines, including the translation and evaluation of the psychometric properties of the questionnaire. Every patient received a standardized assessment, which involved history taking and clinical examination, including the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and the FAI questionnaire. The psychometric analyses included an evaluation of the questionnaire's reliability and validity, as well as an exploratory factor analysis (EFA). Results. Of the 122 individuals enrolled in the study, 63.9% were female. The mean age of the participants was 28.1 years (standard deviation (SD): 6.3). According to the RDC/TMD standards, 40.9% of patients had no TMD, while the FAI assessment indicated that 27% of patients had no TMD. The Cronbach's alpha coefficient for the FAI-PL was 0.75. The exploratory factor analysis revealed 3 factors, accounting for 55.2% of the total variation. The diagnostic sensitivity of the FAI-PL was 98.6%, while the diagnostic specificity reached a level of 65.3%. Conclusions. The Polish version of the FAI is a reliable and valid tool for the screening of TMD symptoms in the Polish-speaking population.