Understanding implementation mechanisms : a cluster-randomized controlled trial in schools

<p dir="ltr">Background: Within the working population, mental health problems are common. To address this challenge, policies and regulations recommend that workplaces systematically assess the psychosocial work environment and act on identified risks. Evidence-based guidelines exist to support this process, but they are seldom used without implementation strategies. However, knowledge about the effectiveness of implementation strategies is inconsistent, with strategies showing mixed effects across studies and settings. This has led to calls for research on the mechanisms through which implementation strategies produce outcomes.</p><p dir="ltr">Aim: This thesis aims to understand the effectiveness of implementation strategies and their mechanisms of change. It compares the effectiveness of a multifaceted implementation strategy with a discrete strategy for implementing the Swedish Guideline for the Prevention of Mental Ill-Health at the Workplace. <b>Study 1</b> focuses on comparing the effectiveness of the multifaceted vs. the discrete strategy on intervention outcomes. <b>Study 2</b> focuses on comparing the effectiveness of the implementation strategies on guideline fidelity from the implementers' and recipients' perspectives. <b>Study 3</b> tests whether the multifaceted strategy leads to larger improvements in capability, opportunity, and motivation, and whether these components mediated the effects of the strategy on fidelity. <b>Study 4</b> used qualitative data to investigate the processes implementers went through with the discrete strategies to achieve fidelity as a downstream outcome.</p><p dir="ltr">Methods: The thesis is based on two cluster-randomized waiting-list controlled trials conducted in Swedish schools. The first trial (2017-2019, 19 schools) tested a multifaceted strategy including an educational meeting, implementation teams, ongoing training, and small cyclical tests of change. In the second trial (2021-2023, 55 schools), the multifaceted strategy was refined and therefore included an additional strategy in the form of implementation facilitation. In both trials, the multifaceted strategy was compared to an educational meeting, but in contrast to the first trial, the implementation team strategy was also part of the discrete strategy in the second trial. <b>Study 1</b>, conducted within the first trial, used a quantitative design in which data were collected on fidelity, psychosocial work environment, and health at baseline, 6 months, and 12 months using questionnaires. Linear Mixed Models (LMM) were used to compare the effectiveness of the strategies on intervention outcomes, as well as to examine associations between guideline fidelity and intervention outcomes. <b>Study 2</b>, conducted in the second trial, used a mixed-method design. Fidelity from school staff (recipients) was assessed at baseline and 12 months using questionnaires, which were analyzed with LMMs. Fidelity from school management (implementers) was measured via a checklist at 12 months, which was analyzed qualitatively. <b>Study 3</b> used a quantitative design in which data on fidelity were collected at baseline and 12 months. Data on capability, opportunity, and motivation were collected after the educational meeting, and at 3 and 9 months. LMMs compared the effectiveness of the strategies on fidelity, and mediation analyses were conducted using the PROCESS macro. In <b>Study 4</b>, process tracing with comparative case studies was used to analyze qualitative data, including interviews and documents, from a subsample of 16 implementers. The analysis followed four steps: (1) constructing a process theory of change, (2) gathering data, (3) coding data through qualitative content analysis, and (4) conducting causal analysis to identify mechanisms and contextual conditions.</p><p dir="ltr">Findings: <b>Study 1</b> found that the discrete strategy was more effective than the multifaceted strategy in improving the primary outcome of exhaustion and some secondary intervention outcomes at 12 months. Higher guideline fidelity was associated with positive outcomes in the work environment and health-related outcomes. <b>Study 2</b> found that the multifaceted strategy was more effective than the discrete strategy in improving guideline fidelity from baseline to 12 months. This was supported by the implementer's perspective, showing a larger proportion of schools that achieved fidelity. <b>Study 3</b> showed that the multifaceted strategy led to larger improvements in capability, opportunity, and motivation. The effect of the multifaceted strategy on fidelity was partially mediated by nine of ten tested mediators, with the largest effects explained by skills and behavioral regulation. <b>Study 4</b> extended these findings by identifying five strategy-specific pathways that illuminated the more proximal outcomes, or strategy-specific milestones, that preceded the more downstream outcome of fidelity.</p><p dir="ltr">Conclusion: Schools benefit from using a multifaceted strategy that can engage multiple mechanisms, promote coordination across organizational levels, and support ongoing implementation when implementing this guideline. This thesis contributes knowledge on the effectiveness of multifaceted, multi-level strategies in workplace settings, as well as provides guidance for both researchers and practitioners on how to design, adapt, and evaluate such implementation.</p><h3>List of scientific papers</h3><p dir="ltr">I. A. Toropova^†, <b>A. Rödlund</b>^†¹, C. Björklund, L. Schäfer Elinder, I. Jensen and L. Kwak. The effectiveness of implementing the Guideline for the Prevention of Mental Ill-health Problems at the Workplace on health-outcomes, organizational and social risk factors: a cluster-randomized controlled trial in Swedish schools. Scandinavian Journal of Work, Environment & Health. 2023;49(6):428-38. <a href="https://doi.org/10.5271/sjweh.4108" rel="noreferrer" target="_blank">https://doi.org/10.5271/sjweh.4108</a></p><p dir="ltr">II. <b>A. </b><b>Rödlund</b>, A. Toropova, R. Lengnick-Hall, B.J. Powell, L. Schäfer Elinder, C. Björklund and L. Kwak. A cluster-randomized controlled trial assessing the effectiveness of a multifaceted versus a discrete implementation strategy on fidelity to an Occupational Guideline for the Prevention of Mental Health Problems at the Workplace: a dual perspective from Swedish schools. [Manuscript]</p><p dir="ltr">III. <b>A. </b><b>Rödlund</b>, A. Toropova, R. Lengnick-Hall, B.J. Powell, L. Schäfer Elinder, C. Björklund and L. Kwak. Mechanisms of change of a multifaceted implementation strategy on fidelity to a guideline for the prevention of mental health problems at the workplace: a mechanism analysis within a cluster-randomized controlled trial. Imple- mentation Science. 2025;20(1):25. <a href="https://doi.org/10.1186/s13012-025-01437-4" rel="noreferrer" target="_blank">https://doi.org/10.1186/s13012-025-01437-4</a></p><p dir="ltr">IV. <b>A. </b><b>Rödlund</b>, A. Toropova, R. Lengnick-Hall, B.J. Powell, L. Schäfer Elinder, C. Björklund and L. Kwak. The Roads Towards Fidelity: A mixed-method study of mechanisms within a multifaceted implementation strategy. [Manuscript]</p><p dir="ltr">¹ †= These authors have contributed equally to this work and should be given equal credit as first authors</p>