Item 4. Introduction (Rationale: implementation strategy and intervention)
The scientific background and rationale for the implementation strategy (including any underpinning theory/framework/model, how it is expected to achieve its effects and any pilot work).The scientific background and rationale for the intervention being implemented (including evidence about its effectiveness and how it is expected to achieve its effects).
Examples
Rationale for the implementation strategy
Rationale for the intervention
Facilitated rapid-cycle quality-improvement techniques (plan-do-study-act cycles [PDSA]) and learning collaboratives are effective in primary care settings, and the two strategies ought to be complementary.21… brief interventions delivered in primary care office settings have affected smoking cessation and alcohol consumption. Although less evidence supports brief interventions for improving diet or increasing exercise, there are reasons for optimism.21
The Health Decision Model, which combines decision analysis, behavioral decision theory, and health beliefs, is useful to identify patient characteristics related to treatment adherence and subsequent blood pressure control… Successful implementation generally requires a comprehensive approach, in which barriers and facilitators to change in a specific setting are targeted.22If not properly controlled, elevated blood pressure (BP) can lead to serious patient morbidity and mortality… Inconsistent patient adherence to the prescribed treatment regimen is known to contribute to poor rates of BP control and improving medication adherence has been shown to be effective in improving BP.22
Explanation
Authors of implementation studies need to explain the rationale for the choice of implementation strategy and for the validity of the intervention being implemented:

  • The implementation strategy and underpinning ‘logic pathway’ will be described in detail in the Methods section (see item 12 for description and table 1 for definition and alternative terminology), but it is likely to be appropriate in the introduction to identify the approach used with supporting evidence for the choice of implementation theory/model/framework adopted (see first example: plan–do–study–act cycles21) and/or any pilot work or examples from other clinical areas or contexts. It will be important to show how the implementation strategy has been adapted to fit the context.

  • The expectation is that there will be (ideally robust) evidence for the intervention (see second example: improving adherence improves BP control which reduces morbidity22). It is important that the strength of evidence is made explicit at the outset,23 especially as sometimes there is pressure to implement an intervention before the evidence base is fully developed (eg, for political imperatives). This will allow a judgement as to whether it is reasonable to assume that effective implementation will have health benefits or whether it is necessary to also assess health outcomes. Effective implementation of some interventions may have such incontrovertible evidence of benefit (eg, reducing smoking prevalence) that a health outcome may be unnecessary. Even when evidence is strong, the possibility that the impact of an intervention may be attenuated when it is implemented in routine practice needs to be considered.


It is recommended that reporting the methods, outcomes and conclusions related to the implementation strategy precedes the corresponding reporting of the health outcomes of the intervention (because the key question in an implementation study is about the impact of the implementation strategy). However, authors may wish to reverse this in the introduction and establish that the intervention is effective before explaining the approach they took to implementing it. The use of hybrid study designs, which combine features of clinical effectiveness and implementation studies, may affect the relative emphasis that is placed on the implementation and health intervention aspects of trials.14