The aims of this study were (1) to design a user-friendly instrument to assess and optimize patient information material (PIM), (2) to develop an English version, and (3) to test its psychometric properties. The instrument was needed to optimize the top-down developed PIM of the psycho-oncological care programme isPO. First, a literature-based PIM checklist was developed by a team of patient representatives, cancer care experts and professional researchers. Next, the checklist's reliability and validity were analysed by having cancer survivors assess the initial and optimized version of the isPO-leaflet. The User-friendly Patient Information Material Checklist (UPIM-Check), developed participatorily, was found to be effective for evaluating PIM. It uses a traffic light scale, and suggestions for improvement can be given for each criterion. Its reliability appeared to be excellent (α = 0.927). The optimized leaflet was rated significantly better than the initial one. The UPIM-Check is a reliable and valid instrument, which enables end-users (e.g., patients) to assess and optimize the quality of PIM according to scientific criteria and the needs of end-users. A bottom-up approach was essential for developing and validating the UPIM-Check. End-users constantly contributed with their specific knowledge. Thus, their position as co-researchers was significantly strengthened.
Keywords: instrument development; patient engagement; patient information material; pilot study; psychometric properties; quality assessment instrument; service provider engagement.