Development and initial validation of the medical fear survey-short version.
The present investigation employs item response theory (IRT) to develop an abbreviated medical fear survey (MFS). Application of IRT analyses in study 1 (n = 931) to the original 50-item MFS resulted in a 25-item shortened version. Examination of the location parameters also resulted in a reduction of the Likert-type scaling of the MFS by removing the last response category ("terror"). The five subscales of the original MFS were highly correlated with those of the MFS-short version. The short version also displayed comparable convergent and discriminant validity with the original MFS in relation to measures of fear, disgust, and anxiety. Confirmatory factor analysis in Study 2 revealed that the five-factor structure of the MFS-short form fit the data well in U.S. (n = 283) and Dutch (n = 258) samples. The short form also had comparable convergent and discriminant validity with the original MFS in relation to domains of disgust in both samples. Receiver operating characteristic (ROC) analysis in Study 3 demonstrated that the subscales of the short version were comparable with the original MFS in classifying participants high (n = 40) and low (n = 40) in blood/injection phobia. Last, structural equation modeling in Study 4 (n = 113) revealed that the MFS-short form demonstrated excellent convergent/discriminant validity with strong associations with injection fear and no association with spider fear. These findings suggest that the MFS-short form has considerable strengths, including decreased assessment time, while retaining sound psychometric properties.