Inappropriate use of clinical practices in Canada: a systematic review

BACKGROUND: Inappropriate health care leads to negative patient experiences, poor health outcomes and inefficient use of resources. We aimed to conduct a systematic review of inappropriately used clinical practices in Canada. METHODS: We searched multiple bibliometric databases and grey literature to identify inappropriately used clinical practices in Canada between 2007 and 2021. Two team members independently screened citations, extracted data and assessed methodological quality. Findings were synthesized in 2 categories: diagnostics and therapeutics. We reported ranges of proportions of inappropriate use for all practices. Medians and interquartile ranges (IQRs), based on the percentage of patients not receiving recommended practices (underuse) or receiving practices not recommended (overuse), were calculated. All statistics are at the study summary level. RESULTS: We included 174 studies, representing 228 clinical practices and 28 900 762 patients. The median proportion of inappropriate care, as assessed in the studies, was 30.0% (IQR 12.0%-56.6%). Underuse (median 43.9%, IQR 23.8%-66.3%) was more frequent than overuse (median 13.6%, IQR 3.2%-30.7%). The most frequently investigated diagnostics were glycated hemoglobin (underused, range 18.0%-85.7%, n = 9) and thyroid-stimulating hormone (overused, range 3.0%-35.1%, n = 5). The most frequently investigated therapeutics were statin medications (underused, range 18.5%-71.0%, n = 6) and potentially inappropriate medications (overused, range 13.5%-97.3%, n = 9). INTERPRETATION: We have provided a summary of inappropriately used clinical practices in Canadian health care systems. Our findings can be used to support health care professionals and quality agencies to improve patient care and safety in Canada.