Objective Variations in definitions, scores, and methodologies have created differences in the results and conclusions obtained from studies on mountaineering and climbing sports injuries and illnesses; this has made interstudy comparisons difficult or impossible. To develop a common, simple, and sport-specific scoring system to classify injuries and illnesses in mountaineering and climbing studies; such retrospective scoring would facilitate the analysis and surveillance of their frequencies, severity and fatalities, and outcomes of any treatment. Methods The UIAA (The International Mountaineering and Climbing Federation) makes recommendations, sets policy, and advocates on behalf of the climbing and mountaineering community internationally through its various commissions. Using a nominal group consensus model approach, a working group was formed during the UIAA Medical Commission's meeting in Adršpach – Zdoňov, in the Czech Republic, 2008. This group critically examined climbing and other relevant literature for various methodological approaches in measuring injury incident rates and severity, including data sources, and produced a working document that was later edited and ratified by all members of the UIAA Medical Commission. Results Definitions of injury location, injury classification, and fatality risk are proposed. Case fatality, time-related injury risk, and a standardized metric climbing difficulty scale are also defined. Conclusions The medical commission of the UIAA recommends the use of the described criteria and scores for future research in mountaineering and climbing sports in order to enable robust and comprehensive interstudy comparisons and epidemiological analysis.