ABSTRACT
BACKGROUND: Overuse of preoperative cardiac testing contributes to high healthcare costs and delayed surgeries. A large body of research has evaluated factors associated with variation in preoperative cardiac testing. However, patient, provider, and system-level factors associated with variation in testing have not been systematically studied. OBJECTIVE: To conduct a systematic review to better delineate the patient, provider, and system-level factors associated with variation in preoperative cardiac testing. METHODS: We included studies of an adult US population evaluating a patient, provider, or system-level factor associated with variation in preoperative cardiac testing for noncardiac surgery since 2012. Our search strategy used terms related to preoperative testing, diagnostic cardiac tests, and care variation with Ovid MEDLINE and Embase from inception through January 2023. We extracted study characteristics and factors associated with variation and qualitatively analyzed them. We assessed risk of bias using the Newcastle-Ottawa Scale and Evidence Project Risk of Bias tool. RESULTS: Twenty-eight articles met inclusion criteria. Older age and higher comorbidity were strongly associated with higher-intensity testing. The evidence for provider and system-level covariates was weaker. However, there was strong evidence that a focus on primary care and away from preoperative clinic and cardiac consultations was associated with less testing and that interventions to reduce low-value testing can be successful. CONCLUSIONS: There is significant interprovider and interhospital variation in preoperative cardiac testing, the correlates of which are not well-defined. Further work should aim to better understand these factors.