Validity and reliability assessment of health belief scales for mammography screening in Greek asymptomatic women

Abstract

The purpose was to assess the validity and reliability of health belief model variables (perceived benefits, perceived barriers, and self-efficacy beliefs) that are often the target of mammography screening interventions. Based on Champion's health belief model scales, questionnaire data were obtained from a nationally representative sample of 408 Greek women, 40 years of age or older and with no personal history of cancer. Using confirmatory factor analysis, we found all items to load significantly on their respective factors. Standardized factor loadings ranged from 0.55 to 0.88. An analysis of localized areas of respecification of a three-factor model revealed that measurement error correlations between a few items existed. Known-groups and criterion-related validity was supported for all scales, while internal consistency reliability of the scales was satisfactory, with Cronbach's alpha ranging from 0.71 to 0.88. The Greek version of the scales measuring perceived benefits, perceived barriers, and self-efficacy beliefs is a reliable and valid tool when used to assess health beliefs for mammography screening among women. Implications for intervention strategies aimed at increasing the likelihood of mammography utilization are considered.