Psychometric Evaluation of the Patient Experience Colonoscopy Scale

Colonoscopy, though common, can be uncomfortable, necessitating routine assessment of patient experience per European guidelines. Positive patient experiences are crucial as they influence willingness for repeat procedures. Patient-reported experience measures (PREMs) effectively capture patient perspectives through surveys, empowering patients to influence healthcare quality. These surveys identify areas for improvement and inform research, enhancing healthcare and its quality. The Patient Experience Colonoscopy Scale (PECS) is a colonoscopy-specific PREM that measures adult patient experience after an elective colonoscopy. It consists of items derived from the patient's perspective and has been found to be content valid. The PECS is multidimensional and divided into five constructs: health motivation, discomfort, information, a caring relationship, and understanding. The current study aims to evaluate the measurement properties of the new PREM, called the PECS regarding reliability and construct validity.

The sample comprised 331 adult patients who had undergone an elective colonoscopy at a University Hospital in Sweden. The PECS was evaluated using intraclass correlation coefficients, confirmatory factor analysis, and multi- and unidimensional Rasch analyses.

The test-retest reliability was acceptable, with an average intraclass correlation coefficient of 0.72. Construct validity was tested with three different techniques. The confirmatory factor analysis revealed that the theoretical bifactor model containing the five constructs was supported. The multi- and unidimensional Rasch analyses showed that approximately 60% of the items had acceptable values. Some violation of local independence and some evidence of differential item functioning with respect to age and gender were identified, but they all made subject matter sense. The PECS is well-targeted to patients with less positive experiences. The overall evaluation of the construct validity showed the PECS has acceptable measurement properties.

The PECS is a reliable and valid 30-item colonoscopy-specific PREM that can play an important role in gathering data for research and quality improvement initiatives that seek to incorporate patient perspectives on colonoscopy experiences. Some potential areas for improvement were found, but the PECS is ready to be utilised in clinical practice for the purpose of collecting patient experiences.