Development and validation of a questionnaire to evaluate infection control in oral radiology

Objectives: To create and validate a questionnaire to evaluate infection control in oral radiology. Methods: The questionnaire was developed after review of the literature, which included published articles and the biosafety protocols available from healthcare agencies. The initial version of the questionnaire was composed of 14 multiple choice questions and was divided into 3 domains on handwashing, disinfection/protection of surfaces and disinfectant used. Content validity was assessed by two expert committees, which reviewed the content and scope of the questionnaire and the relevance of each item, respectively. Reliability was evaluated using test-retest and internal consistency methods with 115 undergraduate dentistry students. Construct validity was assessed using the known-groups technique and factor analysis. The known-groups technique involved 641 undergraduate dentistry students, 20 PhD students and 15 oral radiology professors. In the factor analysis, 3 radiology technicians also participated in addition to the 641 undergraduates, 20 PhD students and 15 oral radiology professors. Results: The content validity results were found to be satisfactory to excellent for the ordinal variables (intraclass correlation coefficient=0.722-1.000) and good to great for the yes/no questions (kappa=0.662-0.913) in terms of reliability and good internal consistency (Cronbach's alpha=0.88). After a factor analysis, some questions were excluded, and the questions were grouped into new domains. Significant differences were observed between answers from different groups. The final version of the questionnaire was composed of nine domains. Conclusions: The questionnaire created was found to exhibit good psychometric properties for assessing infection control in oral radiology.