Is a prostate cancer screening anxiety measure invariant across two different samples of age-appropriate men?

Abstract

Background: In order to explore the influence of anxiety on decision-making processes, valid anxiety measures are needed. We evaluated a prostate cancer screening (PCS) anxiety scale that measures anxiety related to the prostate-specific antigen (PSA) test, the digital rectal examination (DRE), and the decision to undergo PCS (PCS-D) using two samples in different settings. Methods: We assessed four psychometric properties of the scale using baseline data from a randomized, controlled decision aid trial (n = 301, private clinic; n = 149, public). Results: The 3-factor measure had adequate internal consistency reliability, construct validity, and discriminant validity. Confirmatory factor analyses indicated that the 3-factor model did not have adequate fit. When subscales were considered separately, only the 6-item PCS-D anxiety measure had adequate fit and was invariant across clinics. Conclusions: Our results support the use of a 6-item PCS-D anxiety measure with age-appropriate men in public and private settings. The development of unique anxiety items relating to the PSA test and DRE is still needed. © 2012 Linder et al.; Licensee BioMed Central Ltd.