How Multidimensional is Computational Thinking Competency? A Bi-Factor Model of the Computational Thinking Challenge

Abstract

Computational thinking (CT) is an emerging and multifaceted competence important to the computing era. However, despite the growing consensus that CT is a competence domain, its theoretical and empirical account remain scarce in the current literature. To address this issue, rigorous psychometric evaluation procedures were adopted to investigate the structure of CT competency, as measured by Computational Thinking Challenge (Lai, 2021a), in a large sample of 1,130 British secondary school students ( M age = 14.14 years, SD age = 1.45). Based on model comparison from an exploratory multidimensional item response theory approach, the results supported the multidimensional operationalization of CT competency. A confirmatory bi-factor item response theory model further suggested CT competency is comprised of a general CT competency factor and two specific factors for programming and non-programming problem-solving. Despite the multidimensionality, the common variance is largely explained by a primary general factor of CT competency, thus the use of a single scale score is recommended. Psychometric evaluation from the bi-factor model indicated good psychometric properties of the assessment tool. Overall, the bi-factor model provides a useful approach to investigating CT competency and serves as a robust test validation tool.