Non-inferiority and superiority analysis.

BackgroundThe overloading of health care systems is an international problem. In this context, new tools such as symptom checker (SC) are emerging to improve patient orientation and triage. This SC should be rigorously evaluated and we can take a cue from the way we evaluate medical students, using objective structured clinical examinations (OSCE) with simulated patients.ObjectiveThe main objective of this study was to evaluate the efficiency of a symptom checker versus emergency physicians using OSCEs as an assessment method.MethodsWe explored a method to evaluate the ability to set a diagnosis and evaluate the emergency of a situation with simulation. A panel of medical experts wrote 220 simulated patients cases. Each situation was played twice by an actor trained to the role: once for the SC, then for an emergency physician. Like a teleconsultation, only the patient’s voice was accessible. We performed a prospective non-inferiority study. If primary analysis had failed to detect non-inferiority, we have planned a superiority analysis.ResultsThe SC established only 30% of the main diagnosis as the emergency physician found 81% of these. The emergency physician was also superior compared to the SC in the suggestion of secondary diagnosis (92% versus 52%). In the matter of patient triage (vital emergency or not), there is still a medical superiority (96% versus 71%). We prove a non-inferiority of the SC compared to the physician in terms of interviewing time.Conclusions and relevanceWe should use simulated patients instead of clinical cases in order to evaluate the effectiveness of SCs.