ABSTRACT
CONTEXT: Blunt cerebrovascular injury (BCVI) occurs in 1%-2% of all blunt trauma patients. Computed tomographic angiography of the neck (CTAn) is commonly used for the diagnosis and grading of BCVIs. Grade of injury dictates treatment, and there remains a lack in understanding the inter-reader reliability of these interpretations. AIMS: The aim of this study is to determine the extent of variability in BCVIs among specialized neuroradiologist interpretation of CTAn. SETTINGS AND DESIGN: Retrospective review of trauma patients admitted to a level one trauma center with a BCVI from January 2012 to December 2017. Patients were randomly assigned for CTAn re-evaluation by two of three blinded, neuroradiologists. STATISTICAL ANALYSIS USED: The variability in BCVI grades was measured using the coefficient of unalikeability (u), and inter-reader reliability was calculated using weighted Cohen's kappa (k). RESULTS: Two hundred and twenty-eight BCVIs were analyzed with initial grades of 71 (31%) grade one, 74 (32%) grade two, 26 (11%) grade three, 57 (25%) grade four, and 0 grade five. Variability was present in 93 (41%) of all BCVIs. Grade one injuries had the lowest occurrence of total agreement (31%) followed by grade three (61%), grade two (63%), and grade four (92%). Total variability of grade interpretations (u = 100) occurred most frequently with grade three BCVIs (21%). Weighted Cohen's k calculations had a mean of 0.07, indicating poor reader agreement. CONCLUSIONS: This novel study demonstrated the BCVI variability of radiological grade interpretation occurs in more than a third of patients. The reliability of CTAn interpretation of BCVI grades is not uniform, potentially leading to undertreatment and overtreatment.
ABSTRACT
BACKGROUND: Physicians are slow to adopt novel therapies, and the reasons for this are poorly understood. The authors sought to determine if the size of the treatment effect of a novel therapy influences willingness to adopt it. METHODS: We developed 2 experimental vignette pairs describing a trial of a therapy for a hypothetical disease that showed a statistically significant mortality benefit. The size of the mortality effect was varied in vignettes of a pair (3% v. 10%). The 2 experimental vignette pairs differed in whether study enrollment was reported. Vignettes were mailed to a random sample of physicians using an intersubject design. The main study outcome was respondents' willingness to adopt the hypothetical therapy, based on the results of the hypothetical trial. RESULTS: There were 124 and 89 respondents to vignette pairs 1 and 2, respectively. In vignette pair 1, 91% versus 71% of respondents adopted the therapy when it reduced mortality by 10% and 3%, respectively (P = 0.0058). For vignette pair 2, 88% versus 51% of respondents adopted the therapy when it reduced mortality by 10% and 3%, respectively (P = 0.0002). In both vignette pairs, nonadopters were more likely than adopters to report side effects of the therapy as a principal reason for their decision. CONCLUSIONS: In this study, respondents were less likely to adopt a lifesaving therapy if its associated mortality reduction was 3% compared to 10%. Because most therapies for major medical conditions reduce mortality within or below this range, and because there were no opportunity costs associated with the adoption of the therapy, we believe that this effect represents a bias. Further investigation will be required to determine its prevalence and mechanism.
