In this paper, we reviewed the recent literature on the participation and roles of APRN/PAs in the delivery of cancer prevention and screening recommendations in US primary care settings. In the descriptive or intervention research we identified, only 15 studies during a 21 year period, APRN/PAs are involved in recommending cancer screening and prevention. The limited research is somewhat surprising, because a team approach, including physicians and APRN/PAs, has long been recommended for improving healthcare
[18–21, 40]. After receiving the appropriate training, APRN/PAs expect to provide or recommend Pap tests, mammograms and FOBT, while studies only reported on physicians working concurrently with APRN/PAs to screen for cervical cancer
 and colorectal cancer
. With the enactment of the Affordable Care Act, millions of previously uninsured or underinsured will gain access to healthcare. A better understanding of the potential roles of APRN/PAs in meeting this demand for cancer prevention and screening is critical.
The integration of more APRN/PAs into primary care can affect cancer screening and recommendations in several different ways. This integration has the potential to increase the overall percentage of the population ever receiving specific cancer prevention and screening recommendations, as was shown in an intervention study included in this review
. For example, colorectal cancer screening uptake in the US is substantially lower than for breast or cervical cancer screening
. The US Preventive Services Task Force (USPSTF) recommends any of three different tests for colorectal cancer (i.e., FOBT, flexible sigmoidoscopy, colonoscopy)
. These tests have different screening intervals, involvement of specialists, levels of invasiveness and other characteristics
, potentially requiring detailed discussion to allow patients to make informed decisions about screening. Currently, less than 25% of physicians report actually working with APRN/PAs to provide colorectal cancer screening
. However, one challenge with moving forward with team-based health care is that physicians do not always want to work with nurse practitioners
In a time constrained primary care setting, APRN/PAs might play a critical role in improving discussion about options and ultimately improving uptake of colorectal cancer screening. Alternatively, research featuring APRN/PAs might focus on improving all aspects of cancer control among specific populations, such as those previously uninsured or with key risk factors. Lack of health insurance and lack of prior screening has been consistently associated with late stage of disease at diagnosis for breast, cervical, and colorectal cancer
[43–45]. Tobacco use and obesity are associated with many chronic diseases
 and the role of APRN/PAs in encouraging healthy behaviors could improve a variety of health outcomes of the US population. Future research is needed that investigates that relationship between a visit with an APRN/PA and other primary care provider types within team-based primary care that oversamples racial and ethnic minorities and lower socioeconomic status populations.
We identified a number of methodological and reporting limitations in the studies included in this review related to study design and reporting of outcome measures and sample characteristics. Most of the studies were cross-sectional and did not assess cancer prevention or screening outcomes longitudinally. Surprisingly, only three studies reported results of interventions, therefore not allowing for a quantitative analysis of using APRN/PAs for cancer screening or prevention recommendations
[32, 38, 39]. Few reported the type of APRN or PA provider separately, included comparison groups, or were based on well-described samples (Tables
[24–28, 36, 38, 39]. In addition, studies that did include comparison groups did not consistently report on statistical significance of comparisons. Inconsistencies in outcome measure reporting among these studies impacted our ability to compare guideline adherence and patient populations. Few studies evaluated whether screening recommendations were consistent with evidence-based guidelines for patient age at initiation or frequency
[24, 26]. This is particularly important because both overuse and underuse of screening can have adverse patient outcomes
[47–49]. Most of the studies neglected to report patient demographics or key covariates, such as weight, body mass index, and comorbidities, hindering our ability to determine if either physicians or APRN/PAs are providing cancer screening based on guidelines.
Outcome measures were most commonly reported using either provider or patient self-reported data about recommendations and did not report on receipt of service or a documented change in behavior
[24, 25, 30–33, 35, 37]. Even further removed from receipt of service, some studies reported what physicians perceived of APRN/PAs practice
[28, 29]. Self-reported and proxy-reported data may over or underestimate documented receipt of APRN/PA provider services
. Further, primary care addresses multiple preventive services, but only about half of the studies included more than one aspect of cancer control and no studies address post-treatment survivorship care
[24, 26, 27, 31, 37, 39]. Future research should address these limitations and be conducted in longitudinal cohorts with comparison groups of well-described provider types, document patient receipt of screening or prevention recommendations, and assess multiple cancer control recommendations. Use of standardized measures, including for patient characteristics associated with guideline recommendations, evaluation of guideline adherence and longer term patient outcomes will also be important.
Despite using a large number of search terms to identify published studies, manually reviewing all abstracts and relevant reference lists, it is possible we missed some relevant studies. The studies we identified were fairly heterogeneous in terms of patient populations, geographic region, provider type, and type of a comparison group. Additionally, included studies used a variety of approaches to measure cancer screening and prevention, such as physician, non-physician provider and patient self-report, as well as chart review. As a result, our synthesis of findings was descriptive rather than quantitative. Findings are generalizable only to the primary care setting.