Earthquakes pose substantial risks of human health. Preparedness and mitigation strategies can reduce earthquake-related injuries and deaths and information from casualty models that predict earthquake outcomes can help communities prepare. This study identifies epidemiologic and medical risk factors for earthquake casualties, and compares them with engineering casualty models for the purpose of providing evidence that integrates these approaches. It aims to improve earthquake casualty modeling and to offer better accurate estimations. Epidemiological studies that used analytical designs and reported risk factors related to earthquake-induced casualties and studies that examined the association between medical preparedness and earthquake-induced casualties were reviewed. Engineering casualty estimation models were reviewed to identify which risk factors were considered in the models. Epidemiological studies identified the following risk factors: gender, age, socioeconomic status, physical disability and human behavior. Medical preparedness factors were also related to earthquake-induced injury and death. Global casualty estimation models do not currently consider these factors. This study provides evidence that integrating demographic and socioeconomic characteristics of the population and levels of medical preparedness into the existing casualty estimation models may improve their accuracy.