Blood/Injection Fear Scale: Portuguese version, cultural adaptation and psychometric properties in a large sample of primary health care users

Background Blood/injection phobia may have important consequences for health. These phobic individuals, in most cases, avoid contact with health systems, postpone or avoid medical procedures, avoid invasive treatments and do not participate in health promotion and early detection of disease initiatives such as vaccination, consultations, preventive exams or blood donation. Thus, specific and validated instruments are necessary to assess this variable. In addition, a lack of studies on this theme may be associated with the low availability of instruments. This study aimed to propose a Portuguese version of the Blood/Injection Fear Scale (BIFS-P) and assess its psychometric properties. Methods Translation and back-translation were performed. Content validity was assessed in two steps by a panel of 20 experts. The psychometric properties were assessed in a stratified and representative sample of primary health care service users of Ribeirao Preto, southeastern Brazil. Exploratory and confirmatory factor analyses were conducted using a polychoric correlation matrix. Results A total of 1054 primary health care users participated; 79.7% were female and the mean age was 40.6 (standard deviation = 15.16) years. According to the exploratory factor analysis, the items can be grouped into three or five factors with best fits being detected for the three- and five-factor models in confirmatory factor analysis. Conclusion Blood/Injection Fear Scale (Portuguese version) is easy to understand and apply in the general population, showed adequate psychometric properties, and represents an alternative in the assessment of blood/injection phobia for future studies.