The Collaboration and Shared Responsibility in Team Teaching Scale (CSTT)<\/strong> (Decuyper et al., 2023<\/a>) is an empirical psychometric instrument engineered to evaluate core interpersonal and instructional dynamics among educators engaging in co-teaching and team teaching configurations. Developed within the context of primary, secondary, and higher educational settings, the CSTT specifically operationalizes two fundamental dimensions of collaborative pedagogy: Collaboration<\/em> and Shared Responsibility<\/em>. During its initial operationalization, the instrument comprised a 20-item pool derived from established instruments\u2014notably the Student Teachers\u2019 Team Teaching Perceptions Questionnaire (De Backer et al., 2021<\/a>) and conceptual frameworks outlining preconditions for collaborative instructional efficacy (Baeten & Simons, 2014<\/a>; Vangrieken et al., 2017<\/a>). Following expert panel content validation and subsequent psychometric refinement via exploratory and confirmatory factor analyses, the scale was consolidated into a 15-item inventory composed of two distinct latent factors: Collaboration (10 items) and Shared Responsibility (5 items).<\/p>\n The scale employs a standard 5-point Likert response format designed to assess the intensity of collaborative behaviors and joint pedagogical accountability. Psychometric evaluation in a large sample of Flemish educators demonstrated excellent internal consistency, yielding a Cronbach\u2019s alpha of α = .949 for the Collaboration dimension and α = .879 for the Shared Responsibility dimension. Confirmatory factor analysis utilizing weighted least squares mean and variance adjusted (WLSMV) estimation demonstrated strong structural validity and robust model fit indices: χ²(89) = 108.094, p<\/em> = .082, χ²\/df<\/em> = 1.213, Comparative Fit Index (CFI) = .975, Tucker-Lewis Index (TLI) = .971, Root Mean Square Error of Approximation (RMSEA) = .028, and Standardized Root Mean Square Residual (SRMR) = .039. Furthermore, multigroup confirmatory factor analysis substantiated configural, metric, scalar, and strict measurement invariance across educators’ professional experience levels, educational sectors, and team teaching frequencies. The CSTT provides a structurally sound, theoretically grounded diagnostic tool for educational researchers, teacher educators, school psychologists, and academic administrators seeking to measure and cultivate co-teaching efficacy<\/span>.<\/p>\n Collaboration, Shared Responsibility, Team Teaching Scale, Co-Teaching Practices, Educational Measurement, Teacher Professional Development, Structural Equation Modeling, Teacher Attitudes, Instructional Quality, Psychometrics, Measurement Invariance<\/p>\n The Collaboration and Shared Responsibility in Team Teaching Scale (CSTT) was conceived, validated, and published by a collaborative research team based across educational research faculties in Belgium:<\/p>\n The primary purpose of the Collaboration and Shared Responsibility in Team Teaching Scale (CSTT) is to provide an empirically validated, fine-grained diagnostic and evaluative instrument that captures the socio-relational and operational realities of educators engaged in team teaching<\/a>. Team teaching involves two or more teachers working together to plan, execute, and monitor instructional activities for a shared group of students. Although educational institutions globally promote co-teaching models to facilitate inclusive education, differentiate instruction, mitigate professional isolation, and enrich student engagement, the actual pedagogical implementation of team teaching varies tremendously in depth and fidelity. Prior instruments frequently conceptualized collaboration as a unidimensional, general disposition toward collegiality or focused solely on pre-service teacher practicum environments. The CSTT was specifically designed to capture the structural realities of team teaching as enacted in authentic, multi-level educational settings.<\/p>\n In both research and practical school contexts, team teaching can degenerate into superficial division of labor, characterized by parallel teaching or instructional fragmentation, wherein one educator acts as a passive assistant while the other assumes primary responsibility. The CSTT addresses this diagnostic challenge by operationalizing collaboration not merely as spatial co-presence, but as an intersubjective dynamic rooted in professional safety, mutual trust, and reciprocal psychological support, alongside joint systemic accountability for instructional outcomes. By separating and measuring the distinct constructs of Collaboration<\/em> (the relational, communicative, and affective processes) and Shared Responsibility<\/em> (the functional, systemic, and co-owned accountability for curriculum, evaluation, and student development), the scale enables researchers to assess whether co-teaching partnerships are achieving true co-generative learning or remaining superficial arrangements.<\/p>\n In applied educational research, the CSTT enables longitudinal investigations into how collaborative patterns mature over time, how collaborative self-efficacy influences burnout and professional turnover, and how school organizational climates shape teacher teamwork. For teacher educators and school administrators, the tool serves as a reflective instrument for mentoring partnerships, professional learning communities (PLCs), and targeted continuous professional development initiatives. By identifying discrepancies between perceived collaboration and actual shared ownership over student outcomes, school leaders can provide targeted institutional support to scaffold high-functioning collaborative cultures.<\/p>\n The CSTT operationalizes two correlated, yet distinct, latent psychological constructs: Collaboration<\/strong> and Shared Responsibility<\/strong>. These constructs encapsulate the relational mechanisms and joint agency necessary for complex collaborative teaching practice.<\/p>\n The Collaboration<\/em> construct reflects the relational, communicative, and interpersonal ecosystem established between co-teachers. Rooted in psychological safety, interpersonal trust, and professional synergy, this dimension captures the subjective experience of partnership in the shared instructional space. It encompasses the extent to which colleagues perceive each other as competent resources, maintain open lines of dialogue, offer reciprocal emotional and professional scaffolding, and minimize competitive posturing. Within the CSTT, collaboration is defined through ten specific operational manifestations:<\/p>\n The Shared Responsibility<\/em> construct reflects joint pedagogical ownership, shared accountability, and distributed agency regarding core instructional tasks. Distinct from general interpersonal friendliness, shared responsibility requires that co-teachers dissolve individual boundaries of instructional jurisdiction to co-own both the preparatory phases and ultimate outcomes of teaching. This construct addresses the practical question of who holds accountability for the academic and holistic trajectory of the students. The CSTT measures shared responsibility across five critical instructional phases:<\/p>\n The theoretical architecture of the CSTT integrates foundational literature on teacher collaboration, distributed leadership, social interdependence, and communities of practice. It draws directly from the continuum of teacher collaboration articulated by Vangrieken et al. (2017)<\/a> and the comprehensive team-teaching preconditions identified by Baeten and Simons (2014)<\/a>.<\/p>\n At its core, the CSTT is anchored in Social Interdependence Theory<\/a>, originally formulated by Kurt Lewin and extensively expanded by Morton Deutsch and David and Roger Johnson. Social interdependence exists when the accomplishment of each individual\u2019s goals is affected by the actions of others. The CSTT measures positive interdependence<\/em> (cooperation), wherein teachers perceive that they can attain their pedagogical goals if and only if their co-teaching counterpart also succeeds. Under positive interdependence, individuals engage in promotive interaction: mutual assistance, exchange of resources, trust development, and low anxiety. The Collaboration subscale operationalizes these promotive interactions, while the Shared Responsibility subscale operationalizes structural positive interdependence across curriculum planning, instructional delivery, and evaluation.<\/p>\n Vangrieken et al. (2017) established that teacher collaboration exists along a broad spectrum, ranging from low-level joint activities (e.g., informal storytelling, operational information exchange, and independent parallel work) to high-level collaborative arrangements (e.g., team teaching, co-design, joint lesson study, and collective professional identity). Team teaching occupies the deepest end of this spectrum, demanding high structural interdependence and profound autonomy loss in exchange for collective efficacy. Baeten and Simons (2014) synthesized empirical research on student teachers and experienced educators, identifying essential preconditions for team teaching success: compatible pedagogical philosophies, non-competitive psychological safety, structural joint preparation time, and reciprocal feedback. The CSTT operationalizes these preconditions into a coherent psychometric framework, testing whether educators operate in genuine high-level team collaboration or superficial parallel co-presence.<\/p>\n The scale is further grounded in theories of Distributed Cognition<\/a> and Collective Teacher Efficacy (Goddard et al., 2000<\/a>). Distributed cognition posits that pedagogical intelligence and instructional decision-making do not reside in the single mind of an isolated teacher, but are distributed across interactions, instructional tools, and joint actions in the classroom environment. Shared responsibility represents the cognitive and affective convergence of this distributed system: when both educators accept collective responsibility for learning outcomes and student well-being, feelings of isolation diminish, and collective efficacy\u2014the shared belief in a team’s combined capability to execute courses of action required to produce given educational attainments\u2014is strengthened.<\/p>\n The psychometric evaluation of the CSTT demonstrates rigorous evidence of content, construct, and structural validity across multiple developmental and analytical phases (Decuyper et al., 2023<\/a>).<\/p>\n The initial pool of 20 items was developed through a combination of item adaptation and novel construction. Five items on collaboration were adapted from the Student Teachers\u2019 Team Teaching Perceptions Questionnaire (STTPQ; De Backer et al., 2021<\/a>), seven collaboration items were formulated based on Baeten and Simons’ (2014) qualitative preconditions, four shared responsibility items were derived from Vangrieken et al. (2017), and four new shared responsibility items were created to assess student outcomes, well-being, and lesson evaluation. A formal expert review panel comprising specialists in educational sciences, psychometrics, and teacher training assessed the initial item set for syntactic clarity, domain relevance, content breadth, and linguistic appropriateness. Based on expert feedback regarding redundancy and conceptual ambiguity, one item was dropped, refining the pre-testing pool to 19 items.<\/p>\n Construct validity was evaluated using a two-stage factor-analytic framework. Exploratory factor analysis (EFA) on an initial calibration sample confirmed that the items clustered cleanly into a two-factor structure. To maintain strict psychometric standards, items with factor loadings falling below .70 were flagged for removal; four items (C10, SR2, SR7, and SR8) failed to meet this criterion and were excluded. The remaining 15 items demonstrated robust structural validity, cleanly delineating the latent dimensions of Collaboration (10 items) and Shared Responsibility (5 items).<\/p>\n A critical test of an educational assessment tool is whether it measures constructs equivalently across diverse professional demographics. Decuyper et al. (2023) conducted multigroup confirmatory factor analysis (MGCFA) to test for measurement invariance across three primary contextual variables:<\/p>\n The MGCFA supported configural invariance (equivalent factor structure across groups), metric\/weak invariance (equivalent factor loadings across groups), scalar\/strong invariance (equivalent item intercepts across groups), and strict invariance (equivalent residual item variances across groups). This establishes that observed differences in CSTT mean scores across different cohorts reflect authentic differences in collaborative practice rather than measurement artifact or psychometric bias.<\/p>\n The CSTT displays exceptional internal consistency and measurement precision. Reliability analysis conducted on the 15-item finalized scale yielded high reliability coefficients well exceeding standard psychometric thresholds (α ≥ .80 for basic research; α ≥ .90 for high-stakes screening)<\/span>:<\/p>\n The item-total correlations across the finalized set of items remained high, confirming that each item makes an independent, meaningful contribution to its designated latent domain. Invariance tests across educator groups further confirmed that the reliability of the scale remains stable regardless of teachers’ years of professional service or the specific grade levels taught.<\/p>\n The dimensionality of the CSTT was investigated using a combined exploratory (EFA) and confirmatory (CFA) structural modeling approach (Decuyper et al., 2023<\/a>).<\/p>\n The initial 19-item version was evaluated via EFA using principal axis factoring and oblique rotation, acknowledging the expected theoretical correlation between collaborative dynamics and joint responsibility. The eigenvalues and scree plot inspection confirmed a clear two-factor structure. The authors applied a conservative item retention threshold, requiring a primary factor loading of ≥ .70 and low cross-loadings. Four items failed to meet this threshold and were dropped<\/span>:<\/p>\n The resulting 15-item scale featured 10 items loading strongly onto Factor 1 (Collaboration) and 5 items loading onto Factor 2 (Shared Responsibility).<\/p>\n To confirm the two-factor model, a Confirmatory Factor Analysis was conducted using Weighted Least Squares Mean and Variance Adjusted (WLSMV)<\/strong> estimation, which is well-suited for ordinal Likert-type response data. The empirical data demonstrated an exceptional fit to the hypothesized two-factor structural model, with fit indices meeting or exceeding all contemporary thresholds (Hu & Bentler, 1999):<\/p>\n2. Keywords<\/h2>\n
3. Authors<\/h2>\n
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4. Purpose<\/h2>\n
5. Psychological Construct<\/h2>\n
Collaboration<\/h3>\n
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Shared Responsibility<\/h3>\n
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6. Theoretical Framework<\/h2>\n
Social Interdependence Theory<\/h3>\n
The Continuum of Collaborative Practice<\/h3>\n
Distributed Cognition and Collective Teacher Efficacy<\/h3>\n
7. Validity<\/h2>\n
Content and Face Validity<\/h3>\n
Construct and Structural Validity<\/h3>\n
Measurement Invariance<\/h3>\n
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8. Reliability<\/h2>\n
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9. Factor Analysis<\/h2>\n
Exploratory Factor Analysis (EFA)<\/h3>\n
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Confirmatory Factor Analysis (CFA)<\/h3>\n
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