A total of 1,025 article titles and abstracts were screened, and 84 were deemed eligible for full-text screening (Figure). After full-text screening, n = 27 articles were included for data abstraction and synthesis (Table 1). Inter-rater reliability was moderate to strong between both reviewers during inclusion and exclusion screening processes (Κ = 0.728, Κ = 0.866, respectively). Of the 27 included studies in the final sample, more than half of them (n = 19, 70.3%) were based in the US. Two studies were based in Argentina and conducted by the same research team [33, 34]. The remaining individual studies were implemented in the following countries: Canada [35], Ireland [36], Kenya [37], Mozambique [38], Nepal [39], and Vietnam [40]. Overall, most studies (n = 19, 70.4%) were at moderate risk of bias as appraised with the QATSSD rubric.
Study Design, Cancer Types, & Study Settings
Most studies utilized mixed-methods (n = 12, 44.4%) or qualitative methods (n = 12, 44.4%) to conduct their data collection and analyses. Only three studies exclusively used quantitative data, which were heavily drawn from electronic medical records (EMR) [34, 41, 42]. More than 80% of the studies (n = 21, 81.5%) focused on a single cancer site, with cervical (n = 8, 29.6%) and colorectal (n = 8, 29.6%) being the most targeted cancer types. Most studies implemented a cancer screening intervention; only two studies were non-intervention or pre-planning studies [43, 44]. Of the 27 studies, 66.7% (n = 18) took place in a health system, 22.2% took place in a community setting, and three studies were implemented in both contexts [34, 43, 45].
Implementation Science (IS) Frameworks & Characteristics
Nine studies used an IS framework for all phases of implementation, meanwhile half of the studies (n = 13, 48.2%) used an IS framework for post-implementation evaluation [36, 40, 43, 44, 46]. The most common IS framework used across studies was the Consolidated Framework for Implementation Research (CFIR) (n = 13, 48.2%) followed by the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework (n = 7, 25.9%). Less common IS frameworks utilized included the Capability, Opportunity, Motivation, Behaviour (COM-B) Model, Diffusion of Innovations, Health System Framework (HSF), Knowledge-To-Action (KTA), Normalization Process Theory (NPT), Promoting Action on Research Implementation in Health Services (PARIHS), A Practical, Robust Implementation and Sustainability Model (PRISM), and Theoretical Domains Framework (TDF).
Exploratory Findings
Only one-third of studies (n = 9, 33.3%) used an IS framework to address cancer-related health disparities (Table 2) [38, 40, 42–44, 46–49], of which six were based in the US. Of the nine studies, six (66.7%) of them used the CFIR to guide, inform, and adapt the implementation of a cancer prevention intervention to target health disparities [38, 40, 44, 46–48]. Other IS frameworks that were used to inform a health disparities adaptation were Diffusion of Innovations [42], KTA [43], and RE-AIM [49].
Exploratory Findings – CFIR Studies
When the CFIR was used to guide a health disparities adaptation, it was used comparably by studies to inform both contextual and content adaptations. The contextual adaptation most commonly informed by the CFIR and used across five studies was setting. Only one study used the CFIR to guide a format adaptation [48], while three studies used the framework to inform personnel adaptation [38, 40, 48]. [38, 40, 46–48]. Regarding content adaptations, the CFIR was most commonly used by studies to inform the tailoring/tweaking/refining (e.g., language translation) of the existing components of an intervention. Only one study used this framework to inform both the addition and removal of components in an intervention [48].
VanDevanter et al., 2017
In a qualitative study conducted by VanDevanter and colleagues [40], the CFIR was used to identify barriers, facilitators, and modifications to implementing a tobacco cessation program. As a formative evaluation (non-intervention study), VanDevanter and colleagues were interested in how to translate an existing tobacco use treatment program created and tested in a high-income developed country (HIDC) to the local context of a low-income developed country (LIDC) in this case Vietnam. The original intervention included training patients and providers with a toolkit, and a reminder system to prompt providers to identify eligible patients for screening and brief counseling. The adaptation of the intervention to the Vietnamese context was to include a village health worker (VHW), who would provide patients with more intensive cessation counseling. Before implementing this adapted intervention, VanDevanter and colleagues wanted to examine if any barriers and facilitators may exist and if further adaptations were needed.
They identified four potential facilitators within the following CFIR domains: (1) a greater advantage of the intervention compared to existing practice (intervention characteristics), (2) a need to address the burden of tobacco use in the population (outer setting), (3) a demand to increase training, skill-building and leadership engagement (inner setting), (4) and a strong collective efficacy to provide services for tobacco cessation (individual characteristics). Conversely, the following CFIR barriers were uncovered: the perception that the intervention was complex (intervention characteristic) and not necessarily compatible with current workflows (inner setting); and that the Ministry of Health (MOH) has not historically prioritized tobacco cessation and control, and therefore, external resources were lacking (outer setting). VanDevanter and colleagues also identified additional modifications to the intervention, including: (1) lengthening the initial training session with providers and VHWs, and adding a booster session to provide opportunities for these personnels to continually reflect and build capacity; (2) training VHWs as a team rather than individually; and (3) creating an external advisory board consisting of members from the MOH to plan for the sustainability of the intervention.
Cole et al., 2015 & Harry et al., 2019
In qualitative studies conducted by Cole et al. [47] and Harry et al. [46], the CFIR was used to identify domain-specific (e.g., outer setting, inner setting) barriers and facilitators of cancer prevention implementation interventions. Cole and colleagues [47] adapted Systems of Support (SOS), a proactive, mail-based colorectal screening program into U.S.-based federally qualified health centers (FQHCs). The facilitators they identified included the FQHCs’ significant previous quality improvement experience (outer); and previously developed process for pilot testing and evaluating new programs (inner). The barriers they identified included: limited personnel resources (inner); diverse patient population with low health literacy, limited English proficiency, and primary language other than English (inner); communication challenges in the organization and within teams (inner); and large geographic distance between the research team and the FQHC organization leadership staff. Factors that were identified as both barriers and facilitators included FQHC organization reporting requirements. Finally, identified barriers were used to plan adaptations to the original SOS program such as: (1) streamlining FQHC reporting requirements; (2) creating graphically based brochures for patient populations with low literacy or limited English skills, implementation strategies for leadership teams and staff; and (3) creating detailed workflow and implementation plans.
Harry and colleagues [46] identified pre-implementation barriers and facilitators of a clinical decision support (CDS) for cancer prevention. They identified the following outer and inner setting barriers – outer setting included patients’ needs and resources (e.g., limited health insurance coverage, high deductibles), meanwhile inner setting barriers included primary care provider time limitations, electronic medical record alert fatigue, and compatibility of CDS Facilitators included: (1) an increased number of patients seen by PCPs per day (outer); (2) improved patient education (outer); (3) improved patient control of their own health (outer); and (4) CDS would improve cancer prevention and screening quality metrics. Overall, both studies identified multilevel barriers and facilitators to the potential implementation of their respective cancer prevention interventions.
Exploratory Findings – Diffusion of Innovations
In a clinic-based educational program to promote colorectal cancer screening, Tu and colleagues [42] used the Diffusion of Innovations to adapt the intervention, designed initially for a Chinese audience, to a Vietnamese population. The original intervention consisted of a culturally and linguistically appropriate clinic-based educational program to promote CRC screening among Chinese immigrants using small media, a bicultural and trilingual (English, Cantonese, and Mandarin) Chinese health educator, and provision of fecal occult blood test (FOBT) kits. After implementation, the EBI was shown to have a strong effect (adjusted OR = 5.91; 95% CI = 3.25, 10.75). The Diffusion of Innovations was used by Tu and colleagues to guide the contextual adaptations (format and personnel) and content adaptations (tailoring/tweaking/refining, removal elements) of this EBI to a Vietnamese patient population, and was used throughout all implementation phases.
Tu and colleagues adapted the original EBI with: Medical assistants (MAs) serving as the intervention agents instead of a health educator (personnel adaptation); no FOBT kits provided by the MAs as consistent with International Community Health Services procedures (removal of element); and a series of 10–15 minute in-service presentations to the MAs (format). Over two years (2009–2011), the researchers conducted a total of 15 presentations to MAs and two with the staff at the intervention clinic.
Tu and colleagues collected and analyzed pre- and post-measures of CRC screening adherence (for three modalities - FOBT, Sigmoidoscopy, Colonoscopy) at the intervention and control clinics. Both intervention and control clinics had similar overall CRC screening adherence rates at baseline. At post-implementation, the intervention clinic reported a 3% increase whereas the control clinic reported no change in overall adherence rate. During the study period both sites reported decreases in FOBT rates. The intervention clinic also saw an increase in Colonoscopy compared to the control clinic, but this difference was not statistically significant. A subgroup analysis of nonadherent patients at baseline also showed a moderate and significant increase in overall CRC screening adherence (adjusted OR = 1.70; 95% CI 1.05, 2.75) within the intervention arm compared to control arm. Findings from this study highlight that IS-informed adaptations can increase overall CRC screening rates among adherent and non-adherent patients.
Exploratory Findings – Other IS frameworks (KTA, RE-AIM)
In 2011, Lobb and colleagues [43] used the KTA framework to help inform barriers to implementing cancer EBIs (e.g., FOBTs, mammograms, Pap tests) in Canadian health systems and community organizations. Overall, 45 unique barriers to use of mammograms, Pap tests, and FOBTs were identified with limited knowledge among residents; etho-cultural discordance; and health education programs ranked highest for all surveys. Barriers related to cost, patient beliefs, fears, and lack of social support.
Turner and colleagues [49] used the RE-AIM framework to guide and evaluate the implementation of STOP HCC (Screen, Treat, Or Prevent HCC) – a health system-based program designed to promote Hepatitis C Virus (HCV) screening in safety-net primary care practices with large populations of Hispanic patients. STOP HCC was adapted from an intervention that included built-in EMR reminders, posters and handouts about HCV screening, reflex HCV RNA testing, and in-person counseling by a community health worker (CHW) about HCV and follow-up care. STOP HCC adopted the majority of these components with some modifications.
Turner and colleagues used the RE-AIM framework to consider contextual (format, personnel) and content (tailoring/tweaking/refining, adding elements) adaptations for STOP HCC. In STOP HCC, the format was adapted by having CHWs provide remote navigation to patients instead of in-person. In addition to CHWs, STOP HCC had other personnel to assist patients, including nurses, pharmacists, and social services workers. Regarding content adaptations, HCV screening materials were translated in Spanish (tailoring/tweaking/refining), and a mobile application was created and added to educate patients about HCV, HCV-associated stigma and risk factors, and curative options.
STOP HCC was implemented in six health systems (n = 13,334 patients) and instituted for 43 months (October 2014 to May 2018). All practices implemented HCV screening; however, not all contextual and content adaptations were applicable or applied across all health systems (i.e., some health systems exclusively relied on nurses because they did not have CHWs). Pre- and post-measures on HCV screening were reported for all health systems. In the year before STOP HCC implementation, data from four health systems showed that 110 of 13,216 baby boomers (0.8%) had been screened for HCV (pre-intervention). After 29 to 43 months of STOP HCC (depending on site), 13,334 of 27,700 eligible baby boomers (48.1%) were screened, varying by health systems from 19.8–71.3%. By comparison, only 8.3% of 60,722 patients in a national study of community health centers were screened for HCV from 2010 to 2013, and 17.3% of baby boomers were screened nationally in 2017 according to the National Health Interview Survey.