This article describes the process of modification and Polish adaptation of an instrument constructed to assess the level of epistemological understanding. The original tool was developed by Kuhn et al. (Cogn Dev 15:309-328, 2000) in order to account for transitions between, and coordination of, subjective and objective dimensions of knowing across different judgement domains (the domains of personal taste, aesthetics, moral values, truths about the social world and truths about the physical world). Our aim was to improve its psychometric properties. The main changes included extending the list of test items, a new administration procedure and the introduction of a quantitative scoring method. The outcome is a valid, reliable and standardised instrument-the Standardized Epistemological Understanding Assessment.

Abstract. The article describes the construction process of Deductive Flexibility Test  considered a difficult deductive reasoning measure  and the research on correlations between fluency in difficult deductive reasoning and other cognitive abilities. The main goal in the research was to examine the relations between Deductive Flexibility Test scores and results of Raven's Advanced Progressive Matrices  fluid intelligence test. Additionally, the measures of the need for cognitive closure and epistemological understanding were included in the study. The results of the study revealed that Deductive Flexibility Test is a reliable instrument and thus can be used for research purposes. We found low or even no statistically significant correlations between the chosen variables. The directions of further research are discussed.