Using logic model methods in systematic review synthesis: describing complex pathways in referral management interventions

Abstract

Background: There is increasing interest in innovative methods to carry out systematic reviews of complex interventions. Theory-based approaches, such as logic models, have been suggested as a means of providing additional insights beyond that obtained via conventional review methods.

Methods: This paper reports the use of an innovative method which combines systematic review processes with logic model techniques to synthesise a broad range of literature. The potential value of the model produced was explored with stakeholders.

Results: The review identified 295 papers that met the inclusion criteria. The papers consisted of 141 intervention studies and 154 non-intervention quantitative and qualitative articles. A logic model was systematically built from these studies. The model outlines interventions, short term outcomes, moderating and mediating factors and long term demand management outcomes and impacts. Interventions were grouped into typologies of practitioner education, process change, system change, and patient intervention. Short-term outcomes identified that may result from these interventions were changed physician or patient knowledge, beliefs or attitudes and also interventions related to changed doctor-patient interaction. A range of factors which may influence whether these outcomes lead to long term change were detailed. Demand management outcomes and intended impacts included content of referral, rate of referral, and doctor or patient satisfaction.

Conclusions: The logic model details evidence and assumptions underpinning the complex pathway from interventions to demand management impact. The method offers a useful addition to systematic review methodologies.

Trial registration number: PROSPERO registration number: CRD42013004037.

Figure 1

The process of inclusion and exclusion. A flow chart illustrating the process of paper identification.

Figure 2

The completed logic model built from examining the identified published literature. The model illustrates the pathway between demand management interventions and intended impact. It reads from left to right, with a typology of demand management interventions in the first column, the immediate or short term outcomes following the interventions in the second column, then factors which may act as barriers to achievement of longer term outcomes in the mediating and moderating factors column, outcomes in terms of demand management at the level of physicians and their practice in the fourth column, and longer term system-wide impacts in the final column. The model indicates (via differing text types) where there was stronger or weaker evidence of links in the pathway.