and abstracts (Table 1 ). A total of 22 studies met the inclusion criteria [ 26 - 47 ]. We had excellent inter-rater agreement on the selection of eligible studies with a kappa statistic of 0.89 (95% confidence interval = 0.79 to 0.99). Discussion In this systematic review, we identified 79 specific complications that have been used to evaluate acute care trauma hospitals. None of these complications were consistent with a strong clinical recommendation but pulmonary embolism, deep vein thrombosis, and pneumonia were used in over 50% of studies and were therefore consistent with a weak clinical recommendation. Studies included in our review rarely justified the choice of complications included, and they generally had low methodological quality. Standardized definitions should include a consensus on which complications should be used, how they should be defined, and the timing of evaluation [ 15 , 48 , 49 ]. First, the results of this study show that there is currently a lack of consensus on which complications should be used to evaluate trauma care; no single complication was used in more than 70% of studies, only two out of 22 studies shared the same list of specific complications [ 26 , 39 ], less than one-half gave justifications for the complications they used to evaluate care, and only one study demonstrated the clinical relevance of included complications [ 36 ]. This finding is supported by a previous study in a surgical population [ 14 ]. Second, less than one-half of studies provided definitions