Alcohol and cannabis use as risk factors for injury – a case-crossover analysis in a Swiss hospital emergency department

Abstract Background: There is sufficient and consistent evidence that alcohol use is a causal risk factor for injury. For cannabis use, however, there is conflicting evidence; a detrimental dose-response effect of cannabis use on psychomotor and other relevant skills has been found in experimental laboratory studies, while a protective effect of cannabis use has also been found in epidemiological studies. Methods: Implementation of a case-crossover design study, with a representative sample of injured patients (N = 486; 332 men; 154