Reliability and Validity of the Complex Postformal Thought Questionnaire: Assessing Adults’ Cognitive Development

Three studies investigated the psychometric properties of the complex postformal thought (PFT) questionnaire (Sinnott, unpublished scale, 1998; Sinnott and Johnson 1997 ), which is a measure of adult cognitive development. The scale was found to be moderately reliable (α = .63). To assess construct validity, a comparison of participants’ performance on the PFT scale to their performance on the Need for Cognition scale was conducted, which indicated the PFT scale is valid measure of complex thought. Factor analysis reduced the scale to three factors, which correspond to important components of PFT: Multiple Elements, Subjective Choice, and Underlying Complexities. Implications for understanding the nature of adult cognitive development and the usefulness of this new measure for research in this area are discussed.