Reasoning skills or creativity: Which is more important in complex problem-solving?

• The development of IR, CR, creativity and CPS is slow and non-linear. • The most rapid development happens in Grades 6 to 8. • IR, CR and creativity are component skills of CPS. • The roles of IR, CR and creativity change in the development of CPS. • Creativity plays a less significant role in CPS than reasoning skills. This paper focuses on reasoning skills and creativity and evaluates their changing role in the development of complex problem-solving (CPS). Specifically, the aims of the analysis are twofold: first, to monitor the differences in developmental levels of inductive reasoning (IR), combinatorial reasoning (CR), creativity and problem-solving between Grades 5 and 11 to identify periods in which major development takes place; second, to examine the predictive power of IR, CR and creativity for CPS to describe their influential role in the development of problem-solving in general and as they change over time. The sample was drawn from fifth- to eleventh-grade students (aged 10–17) ( N = 9983). The reliability of the online tests proved to be high (EAP/PV reliability=0.884–0.952). The development of IR, CR, creativity and CPS was demonstrably slow and non-linear. The most rapid development happened in Grades 6 to 8. IR, CR and creativity each played a significant role in predicting the level of CPS individually. Their predictive power dropped significantly in the overarching model, thus explaining 71% of the variance of CPS, and changed significantly in the different developmental phases of CPS. The developmental level of reasoning skills strongly explained and influenced the success of CPS, especially between Grades 5 and 8, while the role of creativity dropped greatly after Grade 5. These results confirm and highlight the importance of the explicit development of reasoning skills at the school level, particularly in Grades 6 to 8, which may result – as a transfer effect – in the development of problem-solving skills.