The present study aimed to design and validate a questionnaire to investigate students' perceptions of learner autonomy in the context of Vietnamese tertiary education. The questionnaire was adapted from various well-established scales in the literature, and then the back-translation method was used to produce a version in Vietnamese. After the questionnaire development process, 1,565 non-English majors at seven different tertiary institutions in Vietnam voluntarily participated in the study and completed the questionnaire. Evidence of reliability and validity was provided for the instrument using SPSS Version 24, SmartPLS 3, and SPSS AMOS. Reliability was evaluated using Cronbach's alpha, composite reliability (CR), rho_A value, and average inter-item correlations. Validity was substantiated using Messick's framework of validity (1995). This entailed five different aspects: content, substantive, structural, external, and consequential. The results indicated that reliability reached adequate values and the aspects of validity were mostly confirmed. The questionnaire, therefore, was suited to exploring how students perceive learner autonomy, but it requires more validation for future use in the other contexts.
Keywords: English language learning (ELT); Learner autonomy; Perception; Questionnaire; Validation.
© 2021 The Author(s).