ABSTRACT
This chapter provides step-by-guidance on evaluating the reliability and validity of a contributory factor classification scheme, and then refining the scheme to achieve satisfactory levels of reliability and validity. The application of this process is illustrated by describing an evaluation of the understanding and preventing led outdoor accidents data system (UPLOADS) contributory factor classification scheme. This provides a detailed example of how to conduct, report, and interpret the findings from such an evaluation. Developing a classification scheme that is reliable, valid, and sufficiently detailed for detecting problems is a difficult task. The more categories of contributory factors that are included in the scheme, the more opportunities there are for analysts to misinterpret them. There are many forms of reliability and validity that are relevant to the development of contributory factor classification schemes. The prototype UPLOADS contributory factor classification scheme was initially refined through testing by its creators, other human factors researchers, and then Led outdoor activities practitioners.
