Mixed-Methods Development and Validation of PRO/PREM Items for Patients Undergoing Colon Polyp Surveillance

Patient-reported outcomes (PROs) and experience measures (PREMs) are essential in assessing patient outcomes and experiences in comparative effectiveness research and clinical practice. While validated measures exist for colorectal cancer (CRC) screening, none address colon polyp surveillance. We aimed to develop and validate PRO/PREM items for this purpose.

Using a mixed-methods instrument development design, we conducted semistructured interviews with 14 older adults with a history of colon polyps and 9 primary care physicians and then tested a 16-item PRO/PREM questionnaire. We conducted exploratory factor analyses (EFAs; N=449), confirmatory factor analyses (CFAs; N=466), and test-retest reliability (N=155) to assess validity and reliability.

Interviews revealed 6 PRO/PREM domains: Test Satisfaction, Test Convenience, Testing Complications, Assistance Needed, Confidence in Test, and Cancer Worry. Whereas the EFA results supported a 3-factor solution, the CFA results supported a 1-factor, 4-item model of Test Experience/Satisfaction. Test-retest reliability for this composite Test Experience/Satisfaction score was good. Test-retest reliability was moderate for 12 of the individual PRO/PREM items and poor for 3 items.

To our knowledge, this is the first study to develop and validate PRO/PREM items for adults undergoing colon polyp surveillance. Although subsequent research is required to assess the predictive validity of these items, our findings provide strong initial support for their psychometric properties, and this study represents an essential first step toward implementing PRO/PREM items for colon polyp surveillance in research and clinical settings.