Development, face and content validity of a preoperative functional capacity questionnaire – an observational study

Abstract

Abstract Background functional capacity, defined as the ability of an individual to perform aerobic work, has been shown to have prognostic value in preoperative risk assessment. Greater functional capacity predicts fewer perioperative complications, especially when measured through objective tests, such as the cardiopulmonary exercise test. Nonetheless, objective tests are not widely available, and only a few questionnaires are validated to estimate functional capacity in this setting. Our objective is to describe the development, face, and content validity of a preoperative functional capacity assessment questionnaire that helps identify patients capable of performing 4 or more METs of effort. Method This study followed the STROBE Statement guidance for observational studies. Patients undergoing preoperative risk assessment in a tertiary university hospital were submitted to open interviews about physical activities performed in the last month, and answers were compiled and organized in domains (commuting, household activities, efforts at work, leisure time activities) and estimated efforts in METs. The most frequent answers were used to create the first draft of the questionnaire along with the orientations on how to apply it. The questionnaire was presented to experts for adjustments and, finally, to patients undergoing preoperative risk assessment, leading to the creation of a final version. Results sixty patients undergoing preoperative risk assessment were submitted to the open interviews. The most frequent answers were about household activities or efforts during commuting. Only 22% of the patients reported being employed, but 92% of those also reported performing activities that required 4 or more METs. Nine physical therapists, one physician, one linguistic expert, and 10 patients were responsible for the face and content validity of the questionnaire. The final version comprised 24 questions: 8 about household activities, 3 about work activities, 5 about leisure time activities, and 8 about commuting. Conclusions The preoperative functional capacity questionnaire developed presents face and content validity for its use in the preoperative risk assessment and might increase the accuracy of the preoperative risk prediction.