Psychometric properties of a protection motivation theory questionnaire used for cancer early detection

Cancer is the third cause of mortality in Iran, killing more than 30000 persons annually. The Motivation Theory is a useful approach for predicting and planning intervention programs to change behaviors related to cancer prevention and early detection. Considering the absence of a valid and reliable protection motivation theory questionnaire for cancer early detection in Iran, this study was conducted to design such a questionnaire and assess its psychometric properties in Yazd This was a cross-sectional study. A questionnaire was designed based on similar questionnaires currently in use and its validity and reliability were determined. The reliability coefficients were calculated by Cronbach α and intraclass correlation coefficients. To determine the validity of the scale, two methods were used, namely, face validity and content validity. Confirmation factor analysis was used to determine factorial validity using Amous 21 software. The CVR for all items of the questionnaire, CVI, ICC and internal consistency of the questionnaire were found to be 1, 0.97-1.0, 0.71-0.98, and 0.65-0.93, respectively. The confirmation factor analysis revealed that the questionnaire fitted the Iranian population. The Cronbach alpha coefficient for the questionnaire constructs varied between 0.71-0.98 and 0.65-0.93 The validity and reliability of the Persian version of PMT scale for cancer early detection are acceptable and suitable, so it can be used in similar research.