Table 1.

A comparison of challenges and recommendations for improving intervention fidelity (Toomey et al., 2020) and implementation strategy fidelity

Toomey et al. 2020 (intervention fidelity)		Implementation strategy fidelity
Overarching issue	Specific recommendations	Overarching issue	Specific recommendations
Lack of standardization regarding how fidelity is conceptualized and defined	Clarify how fidelity is defined and conceptualized	Lack of standardization regarding how fidelity is conceptualized and defined	Build consensus definition and conceptualization of implementation strategy fidelity
Limited focus beyond assessing of fidelity of delivery	Consider fidelity beyond intervention delivery 2b. Consider both enhancement and assessment strategies explicitly	Limited focus on assessing implementation strategy fidelity	Increase understanding of barriers and facilitators to implementation strategy fidelity assessment
Limited use of existing fidelity frameworks or guidance	Make use of existing frameworks		Increase focus on implementation strategy fidelity incrementally throughout the strategy’s evolution
Lack of focus on quality and comprehensiveness of fidelity assessment strategies	Consider the psychometric and implementation properties of mixed method fidelity assessment strategies		Utilize mixed methods approaches to fidelity assessment
			Consider the use of the Implementation Strategy Fidelity Checklist (throughout study timeline)
Lack of explicit focus on the balance between fidelity and adaptation	Consider the need for balance between fidelity and adaptation a-priori	Poor reporting on implementation strategy and mechanism specification	Make use of existing implementation strategy specification frameworks
Poor reporting of how intervention fidelity is addressed	Comprehensively report use of strategies to enhance and assess fidelity and results of fidelity assessments	Poor reporting on implementation strategy and mechanism adaptation	Make use of adaptation tracking techniques, assess fidelity to adapted implementation strategies
		Cost of implementation strategy fidelity measurement	Develop innovations to facilitate less costly implementation strategy fidelity measurement