Problem-solving and integration of knowledge are key objectives of the undergraduate dental curriculum of the School of Dentistry, University of Pretoria, which aims to develop the clinical reasoning skills of students. For practical reasons the School provides discipline-based teaching and learning, which, according to the literature, might limit a student’s ability to integrate knowledge during clinical reasoning processes. The literature suggests that problem-solving by means of case studies – an active teaching and learning strategy– might be a useful method to develop and integrate knowledge at undergraduate level, and that earlier exposure to clinical cases might assist in the attainment of clinical reasoning skills at an earlier stage. Hence, this action research study describes the planning, design, implementation and evaluation of a “new” Comprehensive Patient Care curriculum over a three-year period (2009 - 2011) based on Kern’s “six-step approach to curriculum development”. The new curriculum employs an adjunctive integrated case-based approach according to the principles described in the “Four Component Instructional Design Model” and a new variant of the so-called “progress test”, starting already in the preclinical (third) year of study, to develop and test students’ clinical reasoning skills over time. The exit-level progress test results of dental students who had been taught by following an adjunctive integrated case-based approach were statistically analysed, using mixed model statistics, and were compared with the clinical decision-making skills of cohorts who had been taught by following the traditional discipline-based approach. These analyses were complemented by bivariate and multivariate quantitative analyses and qualitative student feedback (mixed methods). The validity of the progress test results was also examined by comparing the results of different cohorts. The fifth-year cohort who had been exposed to integrated case-based teaching and learning from their preclinical year performed significantly better in the progress test at exit level than the cohorts who had received only discipline-based teaching and learning, even when controlling for previous academic performance. These findings were supported by the quantitative and qualitative feedback that students gave about the educational processes that were followed. The progress test performed reasonably well as a measurement tool and all the differences that were measured between the different cohorts could be explained logically. Case specificity posed the biggest threat to the reliability of the test. The results suggest that integrated case-based teaching and learning, commencing in the preclinical study years, might be a useful intervention to improve clinical reasoning ability at exit level in dental schools such as the School of Dentistry, University of Pretoria that follow a discipline-based approach. The results of this action research study provided particularly useful information, which will allow further improvements to the educational intervention. The results of this study require further research to substantiate the findings beyond doubt. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Dental Management Sciences / unrestricted