Measuring circular engagement and transition readiness: development and validation of the attitudes towards circularity questionnaire (ATCQ)

While circular economy research has made major advances in technological and material system innovation, the behavioural foundations of circular transitions remain poorly understood and insufficiently measured. This study develops and validates the Attitudes Towards Circularity Questionnaire (ATCQ), a multidimensional instrument designed to assess circular engagement across cognitive, normative, and behavioural domains. Following a structured instrument development process, expert-based content validation, exploratory and confirmatory factor analyses, and structural equation modelling were combined. Data were collected through a stratified telephone survey among adult residents in Bucharest, Romania (n = 868). Exploratory factor analysis identified an initial five-factor structure, which was subsequently refined through confirmatory factor analysis into a six-factor model comprising circular behaviours, perceived circularity knowledge and competence, environmental concern, normative commitment and institutional trust, personal circular involvement, and professional circularity integration. The instrument demonstrated strong internal consistency and acceptable model fit. Structural modelling showed that normative commitment and institutional trust were strongly associated with circular behaviour, while perceived knowledge was mainly associated indirectly through personal and professional involvement. These findings highlight the importance of social and normative drivers in circular transitions. The ATCQ provides a theoretically grounded tool for measuring circular engagement and offers practical value for monitoring behavioural readiness and supporting circular economy policy and implementation strategies.