Recruitment strategies to promote uptake of cervical cancer screening in the West Region of Cameroon

The Health District of Dschang is divided into 22 health areas, which we separated into four zones based on accessibility to the district hospital (e.g. distances, roads, weather, and transportation means available). Zone 1 was defined as the most accessible area (urban) and Zone 4 the least accessible (rural).

From September 2018 to May 2019, recruitment was entirely based on announcements made and posters hung in women’s associations, churches, and integrated health centers (chief nurses of each center were informed of this project). In Dschang District Hospital’s waiting room, women were invited to participate in the screening program on a daily basis. Two large street banners were hung on the main tar road at the entrance and exit of Dschang for 1 month. Although the banners were hung in zone 1, this route is an access to district services and to markets where farmers weekly trade. Hence, it is used by inhabitants of all zones. The banners’ exposition time was restricted by local authorities as this location was regularly used to announce local events. Local radio announcements were broadcast twice a week for 1 month. The limited duration of broadcasting was due to budget constraints. Radio announcements were made in French which is the official language used in the district. We expected participants to spread information about this campaign to their relatives. The combination of these methods of recruitment is summarized as CIC.

From June 2019 to February 2020, a recruitment strategy using CHW was added to the CIC intervention. At district level, district health managers were informed about the campaign and invited to participate by recruiting CHW. Selection was based on volunteer application without any prerequisites. CHW work in their village. They usually have a main job and act as CHW when called during public health activities. An incentive of 600 CFA (1 USD or 2.62021Int’l$) per woman recruited from June to September 2019 was given, which was then increased to 1000 CFA (1.68 USD or 4.32021Int’l$) since October 2019 to adequately cover cellphone and transportation fees.

In June 2019, 21 CHW attended a half-day informal training. These CHW were based in zone 1. In October 2019, 52 CHW from all health areas (zones 1 to 4) were enrolled in a two-day multi-modal training. Among the trained participants, 5 workers attended both sessions. The second session was based on the “WHO Toolkit for improving CWH Program and Service” [18, 19] and adapted to local barriers by regional caregivers. To differentiate CHW recruitment from CIC, CHW were given invitation vouchers to distribute to each woman they approached. CHW received their financial incentive according to the respective number of vouchers returned by participants attending screening.

Recruited participants were expected to be present at the screening unit at 9 am daily, where a one-hour health education session was provided by trained midwives. General information was given on sexually transmitted infections including HPV (its prevention, cancer development and treatment), contraceptive methods, intimate hygiene, and on the study project (inclusion, exclusion criteria, study procedures, planned follow-up). Participants were asked how they heard about the screening program and were encouraged to spread information about the campaign. Questions were addressed during this time. Participants filled a questionnaire on their socio-demographic characteristics and medical history and proceeded to vaginal self-sampling (Self-HPV) for primary screening. Samples were analyzed using the Xpert HPV assay® (GeneXpert®. Cepheid, 2015. Sunnyvale, California, USA). Results were available within 1 h. HPV-negative participants were advised to repeat screening in 5 years. HPV-positive women underwent triage by visual inspection after application of acetic acid (VIA) and Lugol’s iodine (VILI), and treatment with thermal ablation or large loop excision of the transitional zone (LLETZ) if required. Biopsy and endocervical curettage were performed on all HPV-positive patients for CC exclusion, quality control and further program evaluation. Further details can be found in previously published articles [20, 21].

Before completing their HPV test, participants filled a sociodemographic questionnaire distributed by midwives.

We included for this analysis all women aged 30 to 49 years old living within Dschang’s Health District or its surroundings, who underwent an HPV test from September 2018 to February 2020. Exclusion criteria for HPV screening were pregnancy, hysterectomy, and vaginal bleeding. After verification of inclusion and exclusion criteria, volunteers provided informed written consent to participate in the study. To be counted in the CHW recruitment group, women had to present a CHW invitation voucher.

(i) A comparison of sociodemographic characteristics of women recruited by each method was performed with in-depth analysis for each zone of origin. (ii) The number of participants screened was assessed and costs for the implementation of CHW and CIC interventions compared and (iii) to assess the cost-effectiveness of CHW, the costs and screening recruitment outcomes associated with each intervention were compared to generate an incremental cost-effectiveness ratio (ICER). Costs of recruitment by CHW included workers’ recruitment, training supplies, certification, identification badges, vouchers, transportation, meals, accommodation, incentives, per diem, and miscellaneous materials. CIC costs included radio broadcasting, banners, and poster. Both groups included financial aid for women’s transportation to the screening center according to hospital accessibility from each health area. To highlight the actual field situation and its margin of error, we decided to compare the real-life cost-effectiveness (actual expenses, including incorrect patient transport financial aid), and the theoretical cost-effectiveness (expected expenses) generated by the CHW intervention to the cost-effectiveness of the CIC intervention. Costs are expressed in USD according to the exchange rate on March 1st, 2020 and, in international dollars to consider purchasing power parity.

Quantitative data were stored and analyzed using Stata Statistical Software Release 16 (StataCorp LP, College Station, TX, USA). A descriptive analysis was conducted; categorical variables were summarized with frequencies and percentages, and continuous variables were summarized with means and standard deviations (SD). P-values were estimated using Pearson’s chi-squared test, Student’s t-test, and ANOVA test as appropriate. All analyses were 2-sided and p-values < 0.05 were considered statistically significant. Women’s socio-demographic and medical data were collected, stored, and managed by the secuTrial® online database. The calculated incremental cost-effectiveness ratio (ICER) was determined as the additional cost per screened woman by CHW, calculated as the difference between CHW costs and CIC costs divided by the difference of the number of screened women between CHWs and CIC.

The study obtained approval from the Cantonal Ethics Board of Geneva, Switzerland (Commission cantonale d’éthique de la recherche [CCER], No. 2017–0110) and the Cameroonian National Ethics Committee for Human Health Research (No. 2018/07/1083/CE/CNERSH/SP).

A total of 1940 women were included during the study period, with an HPV positive rate of 18.6% (n = 361), and 39 CIN2+ (2.0%) lesions were diagnosed. In the CIC group, 1356 women (69.9%) were recruited and 28 CIN2+ (2.1%) lesions were detected. In the CHW group, 584 women (30.1%) were recruited and 11 CIN2+ (1.8%) lesions identified. Two hundred sixteen participants living outside the health district of Dschang were recruited in the CIC group, and 19 patients in the CHW group. Among the 68 CHW trained, eight did not recruit any participants. The recruitment progress is depicted in Fig. 1 showing reuptake of the recruitment trend when introducing CHW, and a sharp decrease in recruitment in December due to the annual closing of the Dschang Screening Unit for the winter holidays combined with equipment shortage during that period. Figure 2A-B shows the proportion of women recruited by district zone with each method. Using the CIC method, 87.89% of women were recruited in zone 1 (n = 1002), 7.72% in zone 2 (n = 88), 2.81% in zone 3 (n = 32) and 1.58% in zone 4 (n = 18). With the CHW method, 38.58% of women were recruited in zone 1 (n = 218); 29.03% in zone 2 (n = 164); 13.81% in zone 3 (n = 78); 18.58% in zone 4 (n = 105).

As shown in Table 1, the mean age of participants was 40.2 years old (SD ± 5.9). The two groups differed significantly on all socio-demographic variables (p = < 0.001). However, we did not observe any significant difference between both groups in the proportion of positive HPV test results, HIV self-reported status, and histology among HPV-positive women. Some variables had missing data as a few participants did not answer all questions. Populations recruited by CHW compared to CIC accounted for more divorced and widowed women (11% vs 5.8%) and fewer single women (4.3% vs 8.9%). The predominant education level in the CIC group was secondary (56.0%) and tertiary (23.25%), while in the CHW group, the predominant education level was primary and secondary with 46.9% in each sub-category. Employed and self-employed women were the most represented in the CIC-led intervention at 35.4 and 30.4%, respectively, whereas in the CHW-led recruitment, women were mostly farmers (42.6%) and housewives (25.2%). The unemployment rate in our sample was 0.4%. Women recruited by CHW often had more than 4 children (69.2%) compared to CIC-recruited women, among which 48,8% had between 1 and 4 children and 46.2% had more than 4 children. Tobacco consumption was higher among women in the CHW group (4.6% vs 0.5%). Most women (69.8%) did not use any form of contraceptive. Condom usage was reported by 13.9% in the CIC group compared to 3.6% in the CHW group. Intra-uterine devices, hormonal implants, and injections were used as a contraceptive method for 14.7% of participants in the CIC recruitment group and 20.0% of participants in the CHW group. Previous CC screening was reported by 24.3% in the CIC-led intervention and 3.9% in the CHW-led intervention.

Socio-demographic differences between women recruited by CIC and CHW in the four zones are described in Table 2. Participants’ mean age varied between urban and rural areas, with women in zone 1 tending to be younger than those in zone 4 (p <  0.001). In zone 1, primary education only was attended by 17.4% of women in the CIC group contrasting with 39.5% of women recruited in the CHW group. Furthermore, secondary level and higher was reached by more participants in the CIC group than in the CHW-led intervention except for zone 4, (38.9% in the CIC and 49.5% in the CHW group). Tertiary education was attended by 25.6% in zone 1 recruited by CIC compared to only 7.8% in zone 1 within the CHW group. In the CIC-led intervention, women in zone 1 were more frequently employed (38.1%) and self-employed (33.1%), whereas in zone 2–4, women worked more frequently as farmers (34.1, 34.4 and 50% respectively). In the CHW-led intervention, most participants were self-employed in zone 1 (34.9%), and farmers in zones 2 (49.4%), 3 (92.3%) and 4 (76.2%). We also found that most unemployed women lived in zone 1 and were recruited through CIC. Women coming from zone 1 and recruited through CIC had fewer children than in other zones. Indeed, 49.7% women in zone 1 had between 1 and 4 children and 45.51% had more than 4 children, while in other subgroups, between 62.5 and 80.95% of participants had more than 4 children. Within the CIC-recruited group, most women who used condoms were in zone 1 (15.2%,) and zone 2 (13.6%). Participants who smoked the most were recruited by CHW and live in zone 2 (7.9%) and in zone 3 (12.8%). Variance in previous CC screening was also shown between women living in urban zones compared to those in rural zones and depending on the recruitment method. Among women recruited through CIC, 25.45% of those living in zone 1 had a history of previous CC screening, 15.9% in zone 2, 9.4% in zone 3 and 5.6% in zone 4 (p = 0.092). Rates of previous screening were generally lower in women recruited by CHW, where 7.8% of women in zone 1 had a previous CC screening, 1.2% in zone 2, 2.6% in zone 3 and 1.9% in zone 4 (p = 0.017).

Figure 2C shows recruitment method predominance by health area. We observed a predominance for CHW recruitment in areas distant from the district center.

The cost-effectiveness analysis of recruitment is presented in Table 3.

A detailed breakdown of CHW training costs for each session is presented in the supplemental table. The June session cost a total of 694.98 USD (cost per trained CHW was 33.09 USD for 21 CHW). The October session’s total cost was 1962.88 USD (cost per trained CHW was 37.75 USD for 52CHW). CIC costs include 33.62 USD for four radio broadcasts, 184.92 USD for two street banners, 42.03 USD for a thousand poster. Based on the onsite accounting book, the patients’ transport cost was 1411.30 USD without distinction between the two intervention groups. To compare the two groups, the theoretical patients’ transport cost is presented on Table 3. This was calculated based on the predefined amount allocated to each participant according to hospital accessibility from each health area and amounted to 1845.87 USD for the CHW-led intervention and 1345.74 USD for the CIC-led intervention. The financial incentives paid to CHW were calculated to be around 1141.57 USD (based on receipts when available, and theoretically calculated for participants with missing receipts). The theoretical cost of CHW incentive, based on the total number of women recruited through CHW was 870.40 USD. The average cost per CIC-recruited woman was 1.18 USD compared to 9.20 USD per CHW-recruited woman. Based on theoretical costs, the ICER was 6.45 USD or 16.612021Int’l$ per screened woman recruited by CHW. The average cost per CIN2+ lesion diagnosed was 57.37 USD in the CIC group compared to 488.56 USD in the CHW group.