Discussion
In this study, we present results from a polyvalent CHW model which expanded an existing programme to meet a more diverse set of health needs in a very poor rural setting served by several public health facilities. Assigning CHWs to every household, called the HHM, is increasingly common.30 Our results provide evidence that such a model can expand health coverage by reducing default rates from chronic care and improving uptake of ANC. Importantly, existing HIV programme success was not harmed by the expansion of the CHW role; we did not anticipate or observe changes in HIV retention in care, given long-term survival and retention rates above 90% in Neno district prior to the study.11
A principal aim of the intervention was to improve retention of patients enrolled in NCD care, approximately 5% of whom technically defaulted each month, meaning they had not been seen for eight or more weeks after a missed routine appointment. The NCD clinic cohort at the conclusion of the study was around 12 000 patients, a growth of more than 8000 patients over the course of the intervention, and the intervention reduced the monthly default rate by approximately 0.8 percentage points. This translates into approximately 1200 additional patients being retained in care each year because of the intervention, assuming that none of the defaulters would have otherwise returned to care. This demonstrates how employing polyvalent CHWs to track patients in their homes longitudinally is an effective contributor to retaining patients in care, a critical finding given the significant burden of NCDs in Malawi. Similarly, previous work, including our early work in Neno district, suggests that CHWs can play a key role in increasing ANC visits during the first trimester of pregnancy and maintaining ANC attendance over the course of the pregnancy, a key part of Malawi’s strategic plan.38 39 Our results suggest this effect can be achieved as part of a polyvalent multicondition programme, not only as a result of a vertical programme focused on maternal health.
These results further suggest that improved health outcomes are realised even more when CHW interventions are coupled with a well-designed and well-managed patient-centred clinical programme at the facility level. Neno district has one of the best chronic care programmes in Malawi, as evidenced by excellent HIV and NCD patient outcomes in the Integrated Chronic Care Clinic, a well-coordinated and documented treatment and care programme for clients living with chronic conditions.40 41 Neno did not, however, have outlying malnutrition or TB programmes at the time of the study. Correspondingly, the effect of the HHM on the TB and malnutrition outcomes was not observed. This suggests some level of risk in implementing polyvalent CHW programmes, in that their effects may not be detectable at a facility that does not have correspondingly strong clinical programming or reliable data systems.
This point is underscored by the malnutrition and TB findings. It was hypothesised during intervention design that screening children in the home would identify cases of malnutrition that were missed by community screening, possibly diagnosing children earlier in the course of disease. However, our results do not support the hypothesis that we would see an increase in cases. Process monitoring data collected during the HHM implementation showed that CHWs were reliably visiting households, and monthly meetings, CHW register review and supervisory spot checks did not reveal gaps in performing screening children under 5 for malnutrition each month. It is therefore unlikely that a lack in performing MUAC explains the nutrition results. Several reasons could help explain this. First, the prevalence of undernutrition had been declining in Malawi, following a severe hunger crisis in preceding years, up to and including 2018, so it is logical that case identification in Neno would also decrease.42 43 Second, a supply side problem is possible, as facilities tend not to enrol children when food supplements are stocked out, thus undercounting true diagnoses in the population, and we did not track stock outs as part of this research. Third, there could have been some over-reporting of under 5 malnutrition cases prior to the intervention. This pattern had been observed during times of inconsistent supply; facilities would report extra cases in order to avoid future stockouts. Lastly, though this alone would not explain a decline in malnutrition detection, there could be quality issues with interpretation of MUAC measurement by CHWs as this is more of a technical exercise than they had previously been requested to do.
No evidence was found that the intervention increased the identification of TB cases in Neno district. TB data were limited to quarterly reports rather than monthly, with some quarters having missing data, so we were limited in our power to show a difference. However, results do suggest that having CHWs consistently screen household members for TB and collect sputum is feasible. This is similar to experience in Ethiopia, where 2.4% of those submitting sputum were smear positive.44 CHWs were submitting the majority of the samples examined in Neno district, and 1 in 34 was positive, similar to the findings in Ethiopia.44
This rigorous evaluation of a polyvalent CHW programme in rural Malawi contributes several valuable lessons in the design and implementation of CHW programmes. First, our results suggest that a robust connection to quality primary care is crucial. CHWs perform complementary tasks, as opposed to operating in parallel or as a replacement for primary care. The most significant impacts from the HHM programme correspond to strong primary care programmes in Neno for chronic disease and maternal health.11 41 We found that interventions requiring both CHWs and complex health facility interventions are the most challenging and complex to implement, but present the highest potential as solutions are found. With respect to TB services, the intervention also worked to ensure health facilities had the capacity to examine the increased number of sputum samples referred from CHW TB screening. As a result, the number of patients tested for TB during this period increased. Similar attention needs to be paid to the supply side for paediatric malnutrition and family planning. This discussion around primary care is particularly important considering that many disease-based CHW programmes are subject to vertical funding mechanisms. Our work highlights the need to focus on long-term investment in integrated CHW programmes, thus addressing the continuum of the primary care system best positioned to produce impact at population level.
Second, other components of primary care can have a large impact on findings. Our team acknowledges the role of leadership—facilities with strong leadership, consistent data review meetings and good communication among staff tended to more smoothly take up the intervention and interact with it in positive ways. Additionally, integration of data systems is a complex but necessary challenge. Data systems for CHWs are extremely complex to implement and must be connected to facility data systems. We confronted many hurdles in our attempt to use public data systems, but despite the challenges, we would still recommend this approach in order to strengthen public systems rather than create parallel ones. Indeed, routine evaluation of programmes like this should be incorporated into roll-outs where possible. However, the available data and data quality does limit the ability to isolate impact from components of complex systems requiring CHW action such as referral, laboratory action (such as diagnostic confirmation), and clinical action (such as enrolment).
Finally, our experience with the HHM suggests that the matching of programme aims with CHW skills and competencies is important and warrants more research. For example, factors such as the educational background and training of CHWs may be key, as well as compensation, workload and CHW to household ratios. For example, we did not find evidence of any difference in the uptake of family planning, which could be due to the complexity of the intervention and counselling required or the fact that CHWs may be related/acquainted with their clients, along with external factors such as broader societal issues or religious affiliation of some clinics, or challenges on the facility supply side. Evidence supporting this was found in a different research study, revealing that very few households are asked about family planning by their CHWs (unpublished data). Qualitative follow-up suggested that CHWs reported difficulty discussing sensitive topics such as sexually transmitted infections with their friends and neighbours (unpublished data). Further investigation is ongoing to explain this effect; nevertheless, CHW intervention alone for this complex issue may not suffice without additional complementary culturally appropriate methods.
There are several limitations to this analysis. As indicated the quality of the routinely collected data used for this evaluation (namely DHIS2) is limited in some instances. These data, manually aggregated by overworked clinical staff, are entered in large volumes into the electronic platform by the district data team, which makes them prone to errors.45 Data points were cross-checked against paper records and triangulated with any other comparable data sources or reporting systems. Nevertheless, data for TB and malnutrition were considered of poor quality. Because our data sources were from CHWs and clinical care, we were also not able to track population surveillance data during the study in order to detect changes in population prevalence of specific conditions, such as malnutrition. Second, intervention fidelity was preserved to the extent possible over time, but changes such as health facility staff and leadership turnover, improvements in staff knowledge and changes within the health system external to the CHW programme inevitably occurred. These changes could have impacted our primary (and downstream) indicators that we could not measure explicitly. Indeed, differences in crude and model-based effect estimates suggest a confounding secular trend in the same direction as the intervention effects. Next steps to address some of these limitations include robust initiatives around data quality, particularly for the public sector and ongoing improvement of the new supervision cadre. Ongoing research includes time motion studies to investigate how CHWs allocate their time as well as qualitative research to help explain some of these quantitative findings.
The findings of the study are in agreement with the National Community Health Strategy (2017–2022), which highlights that the provision of quality, integrated community health services that are affordable, culturally acceptable, scientifically appropriate and accessible to every household requires a revised community health system that is designed to be community led. The learnings of connecting the CHWs to the primary care system may be of particular import in this regard, and this work could provide a platform for future standardisation of elements such as training, data systems, linkages to primary care and incentives. The polyvalent, HHM programme provides a model of how the communities can be systematically organised to participate in health, contributing to the strategy’s vision and mission. For example, part of the strategy is to drive down maternal mortality ratio from 439 to 350 per 100 000 live births by promoting ANC facility visits which the HHM programme was able to achieve.
Polyvalent CHW programmes may be able to replicate the success of single focus programmes evidenced in multiple countries while reducing the overall programme cost as workflows are combined. Ultimately, a polyvalent approach such as the household-based model can expand coverage and address a wide range of health needs in a population while maintaining existing gains within disease programmes. In this study, evidence suggests that CHWs can simultaneously improve attendance and reduce default rates across a range of conditions including chronic NCDs, maternal care and HIV care. However, we did not find evidence that CHWs were able to improve nutrition or TB case finding, requiring more complex tasks, although outcomes did not worsen. This may suggest more intensive training is required, that staff with greater experience and qualification are required for these tasks, and/or that the primary care systems need additional strengthening in tandem with community interventions. Further research of polyvalent programmes is required to support their optimal configuration.
