Advancing rural cancer control: A portfolio analysis of research funded by the National Cancer Institute, 2016–2024

Abstract

Purpose:

Given well-documented rural–urban disparities in cancer outcomes, we conducted a portfolio analysis to characterize rural cancer control-focused grants funded by the National Cancer Institute (NCI) between fiscal years 2016 and 2024 and to identify opportunities for future research.

Methods:

ISearch, an NIH portfolio analysis tool, was used to identify rural-focused cancer control research grants funded by NCI. 128 grants were analyzed for key attributes, including grant characteristics (e.g., funding mechanism), cancer site, cancer control continuum phase, research topic, methods, setting, and intervention delivery channel. SAS version 9.4 was used to calculate code frequencies.

Findings:

On average, 14 new grants focused on rural cancer control were awarded per year. Colorectal (n = 36) and breast cancer (n = 27) were the most frequently studied cancer sites. Prevention (n = 43) and treatment (n = 41) were the most frequently addressed phases of the cancer control continuum. Common research topics included quality of care (n = 30), quality of life/mental health (n = 26), and screening (n = 25). Most grants utilized randomized control trials (n = 78) and qualitative research methods (n = 77). Projects were most frequently set in the home (n = 68) or in health care settings (n = 47). Interventions were most frequently delivered through interpersonal interaction, either in-person (n = 40), over the phone (n = 36), or through videoconferencing (n = 27).

Conclusions:

NCI has supported an array of rural cancer control studies since 2016. However, opportunities were identified to further address rural cancer disparities, including efforts focused on understudied topics (e.g., financial toxicity), cancer sites (e.g., cervical cancer), phases of the cancer control continuum (e.g., end-of-life), and settings (e.g., community-based organizations).

INTRODUCTION

Improving health for all Americans will require accelerating reductions in cancer incidence and mortality among individuals who live in rural communities and comprise approximately 20% of the US population.¹ Residing in rural or nonmetropolitan areas has been found to be a strong predictor of worse cancer outcomes, and persistent rural–urban disparities have been documented across the cancer control continuum,^2–5 due to a combination of structural (e.g., limited health care facilities) and behavioral factors (e.g., higher tobacco use) that exacerbate cancer risk and negatively affect screening, treatment, and survivorship outcomes among rural Americans.^2,3,6

In light of these well-documented health disparities, the National Cancer Institute (NCI) elevated rural cancer control as a focal research area in 2016, subsequently launching several initiatives focused on supporting research to improve cancer prevention and care delivery in rural populations,^7,8 including funding opportunities to stimulate research on approaches to improve the reach and quality of rural cancer care (RFA-CA-18–026/RFA-CA-19–064) and interventions addressing modifiable cancer risk factors among rural populations (RFA-CA-20–051). Given the substantial efforts made over the past several years to encourage and support rural research, we undertook an analysis to evaluate recent NCI-funded rural cancer control research, defined as the conduct of behavioral, social, and population science to reduce cancer incidence, morbidity, and mortality, and improve quality of life among those living in rural areas.⁹ The aims of this portfolio analysis were to (1) characterize rural cancer control grants funded by NCI between fiscal years (FY) 2016 and 2024 and (2) identify opportunities to further advance rural cancer control.

METHODS

iSearch, a portfolio analysis platform available to staff at the National Institutes of Health (NIH), was used to identify competitive Type 1 (new) grants funded by NCI between FY16 and FY24 containing the keywords “rural,” “nonmetropolitan,” and/or “nonmetro” in their title or abstract. Rural cancer control funding announcements led by NCI (e.g., RFA-CA-20–051; RFA-CA-19–064) required applicants to define rural populations using Rural-Urban Continuum Codes 4–9, Rural-Urban Commuting Area codes 4–10, and/or Frontier and Remote areas level 4. However, NIH and NCI parent funding announcements, through which a significant proportion of NCI-funded applications are submitted, do not specify how to define rural populations. Therefore, we utilized keyword searches to find rural-focused grants, and did not limit inclusion based on particular definitions of rurality, to maximize identification of relevant rural-focused awards. Only grant mechanisms that fund research projects were included, yielding 214 grants for further screening.

One author (AG) screened titles and abstracts of identified grants for inclusion, and a second author (KB) screened a random 10% sample as a quality check (interrater agreement_inclusion = 100%). Grants were included if they exclusively focused on a rural population or setting, oversampled rural populations, described rural populations as a specific sub-population of interest, or assessed rural–urban differences. Grants were excluded if they were set in rural areas outside the US, focused on basic science,¹ supported research infrastructure only, or had an insufficiently substantial rural component.

After title and abstract review, 135 grants remained for data abstraction. Seven of these were excluded upon full text review (e.g., because the rural focus was found to be minimal), leaving a final set of 128 grants for data abstraction and analysis. The following grant characteristics were abstracted: cancer site, cancer control continuum phase, topic, study design/methods, setting, and intervention delivery channel. Data abstraction was performed by one author (AG) for all grants and a second author (II) abstracted a random 10% sample as a quality check. Interrater agreement ranged from moderate (κ = 0.55, intervention delivery channel) to almost perfect (κ = 0.94, cancer site). For analysis, manually abstracted data were combined with standard administrative data available in iSearch (e.g., grant mechanism, fiscal year) and uploaded to SAS version 9.4 to obtain code frequencies.

RESULTS

Between FY16 and FY24, 14 new rural cancer control research grants were funded per year on average, ranging from six in 2017 to 21 in 2019 (see Figure 1).

FIGURE 1.

Number of NCI-funded Type 1 grants with a rural component by fiscal year.

Over half of the grants were funded under the R01 mechanism (n = 68). Other types of mechanisms, including those meant to fund smaller research projects, like the R21 (n = 8) and R03 (n = 8), were less frequent (see Figure S1).

Cancer site

Colorectal cancer was the most frequently studied cancer type (n = 36), followed by breast cancer (n = 27), all cancer sites/cancer in general (n = 25), and lung cancer (n = 21) (see Figure 2). Grants often focused on multiple cancer sites.

FIGURE 2.

Cancer site(s) targeted in NCI-funded Type 1 grants with a rural component. Note that cancer site codes were not mutually exclusive; therefore, numbers do not total 128.

Cancer control continuum

Most grants focused on the prevention (n = 43) and treatment (n = 41) phases of the cancer control continuum, followed by post-treatment survivorship (n = 31) and diagnosis/screening (n = 26). Few grants addressed end-of-life (n = 4) (see Figure S2).

Topic

Common topics addressed in NCI-funded rural grants included quality of care (n = 30), quality of life/mental health (n = 26), and cancer screening (n = 25). Relatively few grants addressed caregiving (n = 3), palliative care (n = 3), sun safety (n = 3), financial toxicity (n = 2), or alcohol consumption (n = 2) (see Figure 3).

FIGURE 3.

Topic(s) addressed in NCI-funded Type 1 grants with a rural component. Note that topic codes were not mutually exclusive; therefore, numbers do not total 128.

Study designs and methods

Randomized control trials (n = 78) and qualitative approaches (n = 77) were the most frequent research methods utilized. In contrast, longitudinal designs were infrequently utilized (n = 4) (see Figure S3).

Setting

NCI-funded rural intervention projects most frequently took place in study participants’ homes or could be accessed remotely from any location (e.g., text messaging interventions) (“home,” n = 68), followed by interventions that took place in health care settings (n = 47). Few studies were conducted in community settings (n = 10) or schools/childcare facilities (n = 3) (see Figure S4).

Intervention delivery channel

Interventions were most frequently delivered through interpersonal interaction, either in-person (n = 40), over the phone (n = 36), or through videoconferencing (n = 27). Technology-based interventions, including those employing mobile devices (n = 24), websites (n = 25), or electronic health record systems/patient portals (n = 16), were also frequently observed, as was the use of print materials (n = 20) (see Figure S5).

DISCUSSION

The results of this portfolio analysis demonstrate that NCI supports rural cancer control research through a variety of grant mechanisms, and the supported research covers a wide array of cancer types and topics across the cancer control continuum, using a range of different research methods. The findings also revealed several opportunities for future research and initiatives. For example, many included grants were funded through the R01 mechanism, which supports larger research projects with strong preliminary data.¹⁰ Grant mechanisms supporting smaller research projects (e.g., R21, R03) were less frequent. As a complement to R01s, smaller awards are critical for establishing proof-of-concept and gathering preliminary data necessary to develop larger research studies, and could be a target for additional funding support.

Additionally, the finding that colorectal, breast, and lung cancer were the most frequently addressed cancer sites is notable, as research suggests rural cancer disparities are particularly pronounced for cancers with primary and secondary prevention modalities.^3,6 However, the relatively small number of grants focused on cervical cancer suggests an opportunity for future research, given the higher incidence rates of this cancer, particularly at later stages, in some rural populations.^6,11 Furthermore, as higher incidence and mortality has been observed for melanoma in rural areas,^8,12 and rural residents may have higher sun exposure but lower rates of protective behaviors,¹² the limited number of grants focused on skin cancer (or addressing sun safety/UV exposure) among rural populations suggests that this area may benefit from additional research.

Most grants included in the analysis focused on prevention and treatment. Given well-documented barriers to care and treatment disparities in rural areas,³ as well as higher rates of cancer-risk behaviors observed among rural residents,⁶ the focus on these phases of the continuum is consistent with areas of need highlighted in prior research and cancer surveillance efforts. Additionally, these numbers may reflect the impact of NCI funding initiatives that aimed to stimulate research on cancer care and prevention in rural populations. A substantial number of grants also focused on post-treatment survivorship and screening, which are important areas given research showing lower rates of screening¹³ and worse survivorship outcomes (e.g., poorer functioning, higher prevalence of financial toxicity^2,3,14) in rural populations. However, relatively few grants focused on the end-of-life phase of the continuum, despite evidence that rural residents may have less access to, and lower utilization of, end-of-life care¹⁵ such as hospice.^16,17 Additional research to better understand end-of-life care differences in rural areas, as well as efforts to develop interventions addressing barriers to appropriate end-of-life care for rural residents with cancer, might be promising avenues for future work.

Many grants focused on the topics of care quality and screening, which aligns with the access to care challenges observed in rural areas.³ A substantial number of grants also focused on quality of life/mental health, which is important in light of evidence suggesting rural cancer survivors may experience worse quality of life and mental health outcomes than urban survivors.⁸ Additionally, cancer risk factors prevalent in some rural areas (e.g., tobacco use, physical inactivity) were frequently addressed in included grants. However, less attention was given to other risks, such as UV exposure and alcohol consumption, which may be valuable areas for future research as these factors may also vary based on geographic residence.^12,18 Other topics that may warrant additional attention include financial toxicity,^2,19 palliative care,²⁰ and caregiving.²¹

Regarding study methods, few grants utilized longitudinal designs. Longitudinal studies may be helpful for investigating key issues in rural cancer control (e.g., changes in survivorship outcomes—such as quality of life, employment status, and physical functioning—over time^22,23; predictors of cancer-related outcomes such as screening uptake²⁴ and depression in survivors^25,26) and may warrant additional consideration.

Finally, in terms of the settings and intervention delivery methods used in funded studies, few grants leveraged community-based settings, which may play a key role in the social fabric of many rural communities and could be further engaged to advance cancer control efforts. Additionally, although interventions in the included grants were most frequently delivered in person and/or over the phone, many also leveraged digital technology (e.g., telemedicine, mobile devices, patient portals). These technologies may help address some of the access barriers experienced by rural patients.³ However, given potential differences in technology access and digital literacy between rural and urban residents, it is critical to ensure that the use of technology in cancer care does not exacerbate disparities.⁷

Limitations

These findings should be considered in light of several limitations. First, our search strategy may not have captured all rural-focused research funded by NCI. For example, if a grant did not use the words “rural” or “non-metropolitan” in the title or abstract, or used a different but related term (e.g., “frontier county”), it may have been missed. However, prior portfolio analyses and experience suggest that if rurality is not mentioned in the abstract, it is unlikely to be a major focus of the grant. Second, coding for grant characteristics involves a degree of subjectivity, presenting the possibility that some grant features may have been mischaracterized. However, a standardized coding scheme was used to ensure consistency in the coding. Finally, some of the findings may reflect trends present in the overall NCI portfolio rather than being unique to rural-focused grants. For example, the fact that over half of rural grants were funded through the R01 mechanism, while smaller research projects were less common, is consistent with the overall distribution of NCI grants by mechanism.²⁷ However, even if some findings are not unique to rural research funding, this does not negate the need to address these gaps in rural cancer control research specifically, as doing so could help advance work in this area.

CONCLUSION

NCI-supported rural-focused research has increased in the last decade. It is important that future efforts to improve the health of all Americans include a continued focus on rural cancer control. Opportunities remain for future research efforts to address potentially understudied cancer sites (e.g., cervical cancer, skin cancer), topics (e.g., financial toxicity, caregiving), and phases of the cancer control continuum (e.g., end-of-life). Investigators may also consider leveraging a wider range of study settings (e.g., community-based organizations) and study designs (e.g., longitudinal studies) in their future rural cancer control research. The extramural community is encouraged to continue submitting both small and large grant applications focused on rural cancer control, particularly proposals that may address gaps and opportunities highlighted in this portfolio analysis, through NIH and/or NCI parent funding opportunities.

Supplementary Material

Additional supporting information can be found online in the Supporting Information section at the end of this article.