Supplementary material: Questionnaire items investigating software developers' perceptions of the Octalysis Core Drives in requirements change management

This supplementary document outlines the questionnaire items, validity and reliability test results of the perception questionnaire developed based on the Octalysis Core Drives framework, which is designed to evaluate motivational factors in Requirements Change Management (RCM). This instrument consists of 38 items with a Likert scale covering eight core drives (Epic Meaning & Calling, Development & Achievement, Empowerment of Creativity & Feedback, Ownership & Belonging, Social Influence & Relationships, Scarcity & Impatience, Uncertainty & Curiosity, and Loss & Avoidance). This dataset is intended to support transparency and reproducibility in research on gamification and RCM, and can be used by other researchers who wish to evaluate similar constructs in organisational and software engineering contexts.