Operational and organizational variation in determinants of policy implementation success: the case of policies that earmark taxes for behavioral health services.

Background: Research on determinants of health policy implementation is limited, and conceptualizations of evidence and implementation success are evolving in the field. This study aimed to identify determinants of perceived policy implementation success and assess whether these determinants vary according to: (1) how policy implementation success is operationally defined [i.e., broadly vs. narrowly related to evidence-based practice (EBP) reach] and (2) the role of a person's organization in policy implementation. The study focuses on policies that earmark taxes for behavioral health services.

Methods: Web-based surveys of professionals involved with earmarked tax policy implementation were conducted between 2022 and 2023 (N = 272). The primary dependent variable was a 9-item score that broadly assessed perceptions of the tax policy positively impacting multiple dimensions of outcomes. The secondary dependent variable was a single item that narrowly assessed perceptions of the tax policy increasing EBP reach. Independent variables were scores mapped to determinants in the Exploration, Preparation, Implementation, and Sustainment (EPIS) framework. Multiple linear regression estimated associations between measures of determinants and policy implementation success.

Results: Perceptions of tax attributes (innovation determinant), tax EBP implementation climate (inner-context determinant), and inter-agency collaboration in tax policy implementation (outer-context and bridging factor determinant) were significantly associated with perceptions of policy implementation success. However, the magnitude of associations varied according to how success was operationalized and by respondent organization type. For example, the magnitude of the association between tax attributes and implementation success was 42% smaller among respondents at direct service organizations than non-direct service organizations when implementation success was operationalized broadly in terms of generating positive impacts (β = 0.37 vs. β = 0.64), and 61% smaller when success was operationalized narrowly in terms of EBP reach (β = 0.23 vs. β = 0.59). Conversely, when success was operationalized narrowly as EBP reach, the magnitude of the association between EBP implementation climate and implementation success was large and significant among respondents at direct service organizations while it was not significant among respondents from non-direct service organizations (β = 0.48 vs. β=-0.06).

Conclusion: Determinants of perceived policy implementation success may vary according to how policy implementation success is defined and the role of a person's organization in policy implementation. This has implications for implementation science and selecting policy implementation strategies.