Abstract
Background: Self-efficacy is a crucial factor in adopting mammography behavior. A reliable and valid instrument is necessary to measure self-efficacy among Iranian women.
Objective: The aim of this study is to translate the original version of Champion's Mammography Self-efficacy Scale into Farsi and then to estimate the Farsi version's reliability and validity.
Methods: In a cross-sectional study, 200 women 40 years or older who were referred to health centers in Iran were invited to complete the related questionnaires during an interview. Cronbach's [alpha] coefficients and item-total correlations were measured to evaluate the reliability of the scales. Content and face validities were evaluated using the opinions of a panel of experts, and construct validity was estimated through applying confirmatory factor analysis. Logistic regression and [chi]2 tests were used to estimate theoretical relationships.
Results: In terms of reliability, the internal consistency [alpha] was .904 and the test-retest reliability correlation over a 4-week period was 0.624. With regard to the confirmatory factor analysis, the proportion of [chi]2 to degrees of freedom was 0.394, giving a P value of .852 and a root-mean-square error of approximation less than 0.001 with confidence intervals of less than 0.001 and 0.018, with a comparative fit index of 1, normed fit index of 0.999, relative fit index of 0.993, and incremental fit index of 1.
Conclusion: The items that form the self-efficacy measurement scale in the Farsi version are highly reliable and valid.
Implications for Practice: Healthcare professionals and nursing health communities may apply the instrument to determine women's self-efficacy and to plan appropriate educational interventions, aiming at promoting women's mammography behavior.