The search strategy.

BackgroundComputed tomography (CT) scan is a common imaging technique used to evaluate the severity of a head injury. The overuse of diagnostic interventions in the health system is a growing concern worldwide.Objectives: The aim of this systematic review is to investigate the rate of CT scan overuse in cases of mild head injury.MethodsEligibility criteria: We encompassed observational studies—either designed as cohort, case-control, or cross-sectional investigations—that reported on CT scan overuse rates for mild head injuries. Studies had to be published in peer-reviewed, English-language sources and provide full content accessInformation sources: Web of Sciences, Scopus, Medline via PubMed, the Cochrane Library and Embase were searched from inception until April 1, 2023. Studies were included if reporting the overuse of CT scans for mild head injuries using validated criteria.Risk of bias: We used the Risk Of Bias In Non-randomised Studies ‐ of Interventions (ROBINS-I) tool to evaluate the risk bias assessment of included studies. Two independent reviewers evaluated the eligibility of studies, extracted data, and assessed study quality by using the Newcastle-Ottawa Scale.Synthesis of results: Overuse estimates were calculated using a random-effects model. Subgroup analyses were performed to investigate any sources of heterogeneity. Point rate of overuse of CT scans for mild head injuries was the main outcome measured as percentage point estimates with corresponding 95% CIs.ResultsIncluded studies: Of the 913 potentially relevant studies identified, eight studies were selected for the final analysis.Synthesis of results: The pooled rate of CT scan overuse in patients with mild head injury was found to be 27% [95% CI: 16–43; I2 = 99%]. The rate of CT scan overuse in mild head injury cases varied depending on the criteria used. The rate of CT scan overuse was 37% [95% CI: 32–42; I2 = 0%] with the Glasgow Coma Scale (GCS), 30% [95% CI: 16–49; I2 = 99%] with the Canadian computed tomography head rule, and 10% [95% CI: 8–14; I2 = 0%] with the Pediatric Emergency Care Applied Research Network criterion (PERCAN). Based on subgroup analyses, the rate of CT scan overuse in mild head injury cases was observed to be 30% with the Canadian computed tomography head rule criterion, 43% with the National Institute for Health and Clinical Excellence criterion, and 18% with the New Orleans criterion.ConclusionLimitations of evidence: The restricted number of included studies may impact generalizability. High heterogeneity was observed, leading to subgroup analyses based on age, assessment criteria, and study region. Absent data on overuse causes hinders drawing conclusions on contributing factors. Furthermore, this study solely addressed overuse rates, not associated harm or benefits.Interpretation: The overuse of CT scans in mild head injury patients is concerning, as it can result in unnecessary radiation exposure and higher healthcare costs. Clinicians and policymakers should prioritize the implementation of guidelines to reduce unnecessary radiation exposure, healthcare costs, and potential harm to patients.Trial registrationThe study protocol of this review was registered in PROSPERO under the identification code CRD42023416080. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023416080.</div

The overuse of computed tomography for mild head injury by the New Orleans Criterion (NOC).

Random effects model used for analysis (95% confidence interval). The overall rate of CT overuse in mild head injury according to the NOC was estimated to be 18% [95% CI: 5–18; I2 = 97%]. (DOCX)</p

The overuse of computed tomography for mild head injury by the National Institute for Health and Clinical Excellence (NICE).

Random effects model used for analysis (95% confidence interval). The overall rate of CT overuse in mild head injury according to the NICE was estimated to be 43% [95% CI: 13–80; I2 = 99%]. (DOCX)</p

The overuse of computed tomography for mild head injury according to age.

Random effects model used for analysis (95% confidence interval). The rate of CT overuse in mild head injury patients was 36% [95% CI: 14–66; I2 = 99%] in individuals aged 40 years and below, and 20% [95% CI: 13–30; I2 = 92%] in those above 40 years. (DOCX)</p

The overuse of computed tomography for mild head injury according to the region.

Random effects model used for analysis (95% confidence interval). The rate of CT overuse in mild head injury patients was 36% [95% CI: 3–92; I2 = 100%] in Europe, 27% [95% CI: 20–36; I2 = 91%] in Asia, and 20% [95% CI: 5–53; I2 = 98%] in America. (DOCX)</p

Forest plot to assess trends in rate of overuse of computed tomography in mild head injury changes over time using cumulative analysis.

The result of this analysis showed that the rate of CT overuse in mild head injury was 27% [95% CI: 16–43].</p

PRISMA 2020 for abstracts checklist.

BackgroundComputed tomography (CT) scan is a common imaging technique used to evaluate the severity of a head injury. The overuse of diagnostic interventions in the health system is a growing concern worldwide.Objectives: The aim of this systematic review is to investigate the rate of CT scan overuse in cases of mild head injury.MethodsEligibility criteria: We encompassed observational studies—either designed as cohort, case-control, or cross-sectional investigations—that reported on CT scan overuse rates for mild head injuries. Studies had to be published in peer-reviewed, English-language sources and provide full content accessInformation sources: Web of Sciences, Scopus, Medline via PubMed, the Cochrane Library and Embase were searched from inception until April 1, 2023. Studies were included if reporting the overuse of CT scans for mild head injuries using validated criteria.Risk of bias: We used the Risk Of Bias In Non-randomised Studies ‐ of Interventions (ROBINS-I) tool to evaluate the risk bias assessment of included studies. Two independent reviewers evaluated the eligibility of studies, extracted data, and assessed study quality by using the Newcastle-Ottawa Scale.Synthesis of results: Overuse estimates were calculated using a random-effects model. Subgroup analyses were performed to investigate any sources of heterogeneity. Point rate of overuse of CT scans for mild head injuries was the main outcome measured as percentage point estimates with corresponding 95% CIs.ResultsIncluded studies: Of the 913 potentially relevant studies identified, eight studies were selected for the final analysis.Synthesis of results: The pooled rate of CT scan overuse in patients with mild head injury was found to be 27% [95% CI: 16–43; I2 = 99%]. The rate of CT scan overuse in mild head injury cases varied depending on the criteria used. The rate of CT scan overuse was 37% [95% CI: 32–42; I2 = 0%] with the Glasgow Coma Scale (GCS), 30% [95% CI: 16–49; I2 = 99%] with the Canadian computed tomography head rule, and 10% [95% CI: 8–14; I2 = 0%] with the Pediatric Emergency Care Applied Research Network criterion (PERCAN). Based on subgroup analyses, the rate of CT scan overuse in mild head injury cases was observed to be 30% with the Canadian computed tomography head rule criterion, 43% with the National Institute for Health and Clinical Excellence criterion, and 18% with the New Orleans criterion.ConclusionLimitations of evidence: The restricted number of included studies may impact generalizability. High heterogeneity was observed, leading to subgroup analyses based on age, assessment criteria, and study region. Absent data on overuse causes hinders drawing conclusions on contributing factors. Furthermore, this study solely addressed overuse rates, not associated harm or benefits.Interpretation: The overuse of CT scans in mild head injury patients is concerning, as it can result in unnecessary radiation exposure and higher healthcare costs. Clinicians and policymakers should prioritize the implementation of guidelines to reduce unnecessary radiation exposure, healthcare costs, and potential harm to patients.Trial registrationThe study protocol of this review was registered in PROSPERO under the identification code CRD42023416080. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023416080.</div

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram of the search, screen and selection of studies focusing on the overuse of computed tomography in mild head injury.

Of the 913 potentially relevant studies identified, eight studies were selected for the final analysis.</p

Summary of risk of bias.

We assessed risk of bias in included studies utilizing the “Risk Of Bias In Non-randomised Studies ‐ of Interventions” (ROBINS-I) tool. In studies, low risk of bias was observed in confounding and participant selection. One study had low bias in intervention classification, while others had uncertain or high risk. Bias in deviations from intended interventions varied, and most studies had low risk. Bias related to missing data and outcome measurement was generally low or unclear. Selection bias in reported results was low in most studies, with one unclear study.</p

The overuse of computed tomography for mild head injury by the Canadian <i>computed tomography</i> Head Rule (<i>CCHR</i>).

Random effects model used for analysis (95% confidence interval). The overall rate of CT overuse in mild head injury according to the CCHR was estimated to be 30% [95% CI: 16–49; I2 = 99%]. (DOCX)</p