Background: Before the 1970s, research into the development of clinical competence was mainly focused on general problem-solving abilities. The scope of research changed when Elstein and colleagues discovered that individual ability to solve clinical problems varies considerably across cases. It was concluded that problem solving abilities are highly dependent on domain-specific knowledge rather than on general problem solving skills. Elstein called this phenomenon "case specificity." Purpose: The finding of content specificity will be contrasted with the existence of a general clinical problem solving ability, and the relationship between preclinical knowledge and a problem solving ability will be investigated. Methods: A correlation matrix was calculated with clerkship final scores from 10 disciplines to examine the magnitude of the interrelations. A confirmatory factor analysis was applied to the corresponding covariances using structural equation modeling to investigate whether scores on finals shared any common variance across clerkships. Finally, two additional models were tested to examine the nature of the relationship between preclinical knowledge and problem solving. Results: Low to moderate correlations across clerkship disciplines were found, supporting the original findings of content specificity. Further investigation showed that in addition to specific knowledge, a general, content-independent ability is needed to perform on these examinations. Conclusions: Clinical competence, as measured in this study, is based on a "combination" of specific preclinical knowledge and a problem-solving ability. Case specificity fits perfectly well in this interactional perspective on clinical problem solving but does not explain it. The phenomenon "case specificity" is therefore not solely a result of content knowledge, but of level of experience and level of case difficulty.