Development and content validity of the Patient Safety in Radiation Oncology questionnaire (PaSaRO): A multi-method study

BackgroundCurrently, no comprehensive tool exists to systematically assess patient safety in radiation oncology (RO). To address this gap, we developed the Patient Safety in Radiation Oncology questionnaire (PaSaRO), a German instrument enabling RO professionals to evaluate patient safety within their departments. MethodsBuilding on a literature review identifying 145 patient safety indicators (PSIs), we determined further PSIs via two focus groups with RO professionals, patient interviews, and expert consultations. RO professionals were recruited through professional networks and societies, while patients were recruited as a convenience sample at a university hospital centre. Content validity was ensured by assessing relevance and comprehensiveness through a Delphi study and comprehensibility through cognitive interviews with RO professionals. FindingsTwo focus groups generated 48 new PSIs, while nine patient interviews contributed 15 PSIs, and three experts suggested 12 more. In combination with the PSI from the review, a total of 213 PSIs were compiled and subsequently rated in the Delphi study by 84 professionals in the first round and 72 in the second. During this process, seven additional PSIs were suggested, and 158 were ultimately deemed relevant. In cognitive interviews, 43 PSIs were linguistically refined to improve clarity. InterpretationThis study produced a pilot version of the PaSaRO, comprising 158 consensus-based PSIs--the first comprehensive questionnaire specifically developed for RO. The rigorous multi-method development process ensures strong content validity. Future research will conduct psychometric evaluation, after which PaSaRO may serve as a standardized tool for assessing, monitoring, and improving patient safety in RO.