Table 1

Strength of evidence for primary prevention of sports-related concussion

StudyOverview and resultsRisk of biasQualityImportancePICO questions
Benson et al 38 Prospective cohort. Compared half vs. full face shield hockey helmets. No difference.RR=0.97 (0.61–1.54).UnlikelyLow ⊕⊕Low4
Benson et al 39 Prospective cohort. Evaluated prior data set evaluating sessions of play lost due to concussion relative to half vs. full face shield hockey helmets. More sessions lost for half vs. full.RR=4.07 (3.48–4.74).UnlikelyLow ⊕⊕Low4
Black et al 52 Prospective cohort. Significantly increased risk of concussion when body-checking is allowed in youth hockey. IRR=2.83 (1.09–7.31). LikelyModerate⊕⊕⊕Low5
Black et al 53 Retrospective cohort. Significant reduction in concussion in youth hockey league comparing year before and after implementation of rule prohibiting body-checking. IRR=0.34 (0.21–0.56).LikelyVery low⊕Very low5
Collins et al 36 Prospective cohort. Compared new vs. standard-design football helmets. Significant decrease with new design.RR=0.69 (p<0.027).LikelyModerate⊕⊕⊕High4
Collins et al 67 Prospective observational. Evaluated correlation of preseason neck strength measurements and incidence of concussion in high school athletes. Significant correlation with mean neck strength but no comparison of exercise vs. no exercise.UnlikelyVery low⊕Low7
Collins et al 43 Retrospective. No difference in concussion rate between new and recertified helmets. Data suggest difference between helmet brands.UnlikelyLow ⊕⊕Low4
  • IRR, incidence rate ratio; RR, relative risk; PICO, population, intervention, comparator, and outcomes.