Dataset for "Middle leadership and instructional quality in Vietnamese secondary schools: a multilevel comparison across disadvantaged and non-disadvantaged contexts"

Title Dataset for “Middle leadership and instructional quality in Vietnamese secondary schools: a multilevel comparison across disadvantaged and non-disadvantaged contexts” Description Overview This dataset supports the study examining multilevel instructional mechanisms linking middle leadership practices with instructional quality across disadvantaged and non-disadvantaged Vietnamese secondary schools. The study investigated how middle leadership contributes to professional learning collaboration, instructional coordination, teacher self-efficacy, instructional innovation, and instructional quality within subject departments operating under curriculum reform and digital transformation in Vietnam. The dataset was analyzed using multilevel structural equation modeling to distinguish teacher-level instructional processes from department-level collective professional capacity across contrasting institutional contexts. Research Context Vietnamese secondary schools currently operate under substantial instructional transformation associated with competency-oriented curriculum reform, digital pedagogy, interdisciplinary teaching expectations, and increasing professional accountability. Subject departments consequently function as important organizational units responsible for curriculum coordination, instructional coherence, collaborative professional interaction, and pedagogical adaptation. Disadvantaged schools frequently experience greater instructional complexity, fewer professional resources, and more constrained institutional conditions than non-disadvantaged schools. Comparative analysis was therefore conducted to examine whether multilevel instructional pathways differed across contrasting school contexts. Participants The dataset includes responses from 592 teachers nested within 66 subject departments across Vietnamese secondary schools. Sample characteristics include: 249 male teachers and 343 female teachers 57.77% of participants possessing more than ten years of teaching experience 261 teachers from disadvantaged schools 331 teachers from non-disadvantaged schools Teachers represented multiple disciplinary areas, including: Mathematics and Informatics Natural Sciences Social Sciences Language Arts Foreign Languages Other subject departments Research Design The study employed a multilevel quantitative design using teacher survey data aggregated within subject departments. Teacher-level mechanisms and department-level collective mechanisms were examined simultaneously through multilevel structural equation modeling. The analytical framework investigated: Teacher-level instructional pathways Department-level collective professional capacity Comparative differences between disadvantaged and non-disadvantaged school contexts Variables and Constructs The dataset includes six major latent constructs measured through 24 questionnaire items using a seven-point Likert scale ranging from 1 (strongly disagree) to 7 (strongly agree). Constructs include: Middle Leadership Practices (MLP) Professional Learning Collaboration (PLC) Instructional Coordination (IC) Teacher Self-Efficacy (TSE) Instructional Innovation (INI) Instructional Quality (INQ) Aggregated department-level variables were additionally generated for multilevel analysis. Questionnaire Structure Middle Leadership Practices measured instructional guidance, mentoring support, instructional monitoring, and professional support provided by department leaders. Professional Learning Collaboration assessed knowledge sharing, collaborative reflection, joint lesson planning, and peer professional support within subject departments. Instructional Coordination measured curriculum alignment, lesson coherence, instructional pacing, and assessment consistency across classrooms. Teacher Self-Efficacy assessed instructional confidence, classroom management capability, adaptive instructional competence, and support for student learning. Instructional Innovation examined student-centered pedagogy, adaptive instruction, innovative teaching approaches, and technology integration. Instructional Quality evaluated instructional clarity, teaching effectiveness, student engagement, and instructional support. File Contents The dataset includes: Teacher identification variables Department identification variables School context classification variables Raw questionnaire item responses Composite construct scores Aggregated department-level variables Key variables include: team_id teacher_id Dis MLP1–MLP4 PLC1–PLC4 IC1–IC4 TSE1–TSE4 INI1–INI4 INQ1–INQ4 MLPm–INQm MLPtm–INQtm Analytical Approach The study applied multilevel structural equation modeling using Mplus with maximum likelihood robust estimation. Measurement validity was evaluated through: Composite reliability Average variance extracted Fornell–Larcker criterion Heterotrait–monotrait ratio Structural relationships were evaluated through: Standardized path coefficients Indirect effects Explained variance Effect size estimates Comparative subgroup analysis Main Findings The findings indicated that middle leadership significantly strengthened professional learning collaboration, instructional coordination, and teacher self-efficacy at the teacher level. Instructional innovation demonstrated a strong positive relationship with instructional quality. Department-level findings revealed that middle leadership substantially influenced collective teacher self-efficacy, highlighting the importance of collective professional capacity within subject departments. Comparative analysis further demonstrated stronger instructional coordination and instructional innovation pathways within disadvantaged schools, whereas non-disadvantaged schools demonstrated stronger leadership influence on collective teacher self-efficacy at the department level. Keywords Middle leadership; instructional quality; multilevel SEM; teacher self-efficacy; instructional innovation; disadvantaged schools; Vietnamese secondary education; instructional coordination; collaborative professional capacity; educational leadership