The project team conducted a targeted literature review of existing evidence related to the effectiveness of clinical-community resource relationships for the delivery of select preventive services. That review served as the basis for an assessment of evidence gaps. The literature review and gaps assessment served as a basis for this Roadmap. The literature review included studies related to the eight clinical preventive services listed below, all USPSTF A or B recommendations. Based on input from the expert panel, these services could potentially be provided in non-clinical settings and are candidates for delivery through a clinical-community relationship:
- Alcohol misuse screening and counseling.
- Breastfeeding counseling.
- Healthy diet counseling for adults with known risk factors for cardiovascular and diet-related chronic disease.
- Obesity screening and counseling for adults.
- Obesity screening and counseling for children.
- Sexually transmitted infections (STIs) counseling.
- Tobacco use counseling and interventions for non-pregnant adults.
- Tobacco use counseling for pregnant women.
In addition, the literature review specifically assessed evidence on counseling to promote physical activity as an aspect of screening and counseling for obesity.
AHRQ had funded an earlier targeted literature review of clinical-community resource relationships for delivery of preventive services that address healthy diet, physical activity, obesity, or tobacco use (Porterfield et al., 2012). The investigators of that review found the evidence base to be small and heterogeneous, and suggested that it was still insufficient for a focused systematic review. Therefore, the literature review conducted for the current project was also a non-systematic targeted review; the review was broadly inclusive of studies that had assessed the effect of clinical-community resource relationships on patient outcomes related to any of the preventive services of interest. It did not include quality assessments of included studies or a summary assessment of the strength of evidence.
Consistent with the earlier findings of Porterfield et al. (2012), the review found that the evidence base was sparse. Most of the existing research addresses tobacco cessation counseling for non-pregnant adults (16 of 27 studies) or obesity screening and counseling for adults (15 of 27 studies), with few studies identified for other preventive services. No evidence was identified for three of the eight preventive services—breastfeeding counseling, obesity screening, and counseling for children, and counseling for STIs. Additionally, the existing evidence is very heterogeneous in the interventions, outcomes, and settings studied; with a lack of sufficient numbers of studies of promising interventions using common outcomes to allow for rigorous comparisons of effectiveness. This dearth of evidence suggested that the general topic of the effectiveness of clinical-community resource relationships for providing clinical preventive services is broadly understudied.
Based on the findings of the literature review, we engaged a panel of eight national experts to provide input regarding the evidence reported in the review and to identify and characterize gaps in the evidence. Panel members had specific experience and expertise in collaborations between primary care and public health agencies and linking primary care with community resources for clinical preventive services. The panel spent half a day engaged in an in-person, facilitated and structured process to identify and characterize evidence gaps. Two members of the panel further clarified and elaborated on a preliminary written synthesis of the full panel’s conclusions. The full panel was then reconvened for a teleconference meeting to finalize the gaps report.
We classified evidence gaps according to current recommendations (Chang et al., 2012) into content gaps, which relate to particular questions or aspects of questions, and methodological gaps, which relate to multiple key questions. We further classified content gaps as they relate to each element of the “PICOS” format–population (P), intervention (I), comparison (C), outcome (O), and setting (S). The great majority of identified evidence gaps (31 of 42) were relevant to most or all of the clinical preventive services of interest. This was particularly true given that approximately one quarter (7 of 27) of the included studies were of interventions that targeted multiple preventive services.
The targeted literature review was broad in scope and addressed a general question without specific key questions. In addition, as previously noted, the evidence base was sparse and heterogeneous, with no evidence for several preventive services. As a consequence, many of the gaps identified by the panel were essentially described as general research needs, rather than as discrete gaps in evidence, which, if filled, would answer specific research questions.
Methodological gaps were articulated in broad terms and suggest the need for foundational research ranging from cluster randomized trials of the effectiveness of clinical-community resource relationships to qualitative research into the myriad of contextual factors that may influence the effectiveness of such relationships. The gaps report, along with the sparse evidence of existing measures, formed the basis of the priority questions and recommendations of this Roadmap.