Aim. To explore patients’ experiences before, during and after a colonoscopy andto develop and psychometrically evaluate a colonoscopy-specific patientreportedexperience measure.

Methods. Patients who had undergone a colonoscopy for the first time wereinterviewed about their experiences of the procedure in Study I. The interviewswere analysed using thematic analysis. In Study II, a systematic literature reviewwas conducted by including 13 studies of a qualitative design that described howadult patients experienced colonoscopy, and meta-ethnography was used forsynthesis. In addition, triangulation was used to explore similarities anddifferences between existing colonoscopy-specific patient-reported experiencemeasures (PREMs), and a conceptual model was created describing theexperiences of adult patients before, during and after colonoscopy. Based onStudies I and II, a new colonoscopy-specific PREM was developed in Study III, first through operationalisation and then by evaluating its content validity usingface validity, cognitive interviews and a content validity index. Patients andhealthcare professionals with colonoscopy experience were involved in the development process. Study IV, finally, evaluated both the reliability of the colonoscopy-specific PREM developed in Study III, using intraclass correlation coefficients, and its construct validity, using confirmatory factor analysis and multi- and unidimensional Rasch analyses.

Results. In Study I, adult patients’ experiences of first-time colonoscopy were described and presented in a thematic map with four main themes: ‘making up one’s mind’, ‘getting ready’, ‘going through’ and ‘finally over’. In Study II a conceptual model was developed consisting of five concepts: health motivation, discomfort, information, a caring relationship and understanding, and three time periods: before, during and after. No existing colonoscopy-specific PREM had items that fully reflected the conceptual model (Study II). A new colonoscopy-specific PREM was therefore developed and named the Patient Experience Colonoscopy Scale (PECS) in Study III. The constructs and the initial 77 items were derived from the conceptual model. The content validity of the PECS wasconfirmed to be relevant by healthcare professionals and, most importantly, bypatients from the target population in Study III. In Study IV, the test-retest reliability values were interpreted as acceptable. In addition, the combined result of the construct validity evaluation showed acceptable values, supporting the structure of the PECS (Study IV). After psychometric evaluation, 30 PREM items remained.

Conclusion. Patients’ experiences of colonoscopy are individual and the ability of healthcare professionals to meet patients’ needs is vital (Study I). Colonoscopy-specific patient experiences are, furthermore, multidimensional, and they were visualised in a conceptual model that was not reflected in any existing PREMs (Study II). The PECS is a developed PREM based on a theoretical understanding of the patients’ experiences of colonoscopy, and its content validity was shown to be relevant (Study III). Psychometric evaluation of the reliability and construct validity of the PECS showed acceptable measurement properties in a Swedish population of adults who had undergone at least one colonoscopy (Study IV). Future clinical use of the instrument will show whether potential areas for improvement need to be addressed. The PECS is now ready for use in clinical practice and research, facilitating the collection of the patient perspective on colonoscopy.