The C4P tool allows programme managers working in low- and middle-income countries such as Tanzania to work with a study team and stakeholders to co-create a projection of the incremental costs of scaling up their programmes, for primary, secondary and tertiary prevention. The tool is a central part of a process that allows programme managers to consider the financial implications of alternative approaches to scaling up a cervical cancer programme. Furthermore, it acts as a catalyst for key stakeholders to engage in substantive discussions about how they can coordinate their efforts to avoid bottlenecks and gaps in the service delivery workflow. As the process of completing the tool progresses, programme managers, policymakers, donors and funders ideally will reach a convergence in their understanding of what needs to be done and how much it will cost to do it. This, in turn, aids champions of a cervical cancer programme to plan and advocate for resources for their programme so that they can reach their goals of reductions in mortality and morbidity and eventually elimination.
The process to estimate the costs of scaling up a comprehensive cervical cancer programme involves setting up a team of health economists, epidemiologists, clinicians and programme managers from both the immunization and the cancer units or programmes. Using the C4P tool effectively requires a trained health economist to be part of the study team and therefore involves training local health economists to use the tool. An additional benefit of the process is that the health system is strengthened since the capacity of local health economists in costing health programmes is improved.
The results of the pilot in Tanzania indicate that the cost driver for vaccination is vaccine procurement (58% and 71% of financial and economic costs, respectively). For non-vaccine costs, the cost driver is service delivery (33% and 24%, respectively), i.e. personnel salaries (for economic costs), transport and per diem. Programmatic activities (i.e. microplanning, training, sensitization and monitoring and evaluation) comprise a smaller proportion (8% of financial costs and 5% of economic costs) since these improve service demand and quality. The costliest programmatic activity is monitoring and supervision.
When the projected costs of vaccination are compared to the 2012 study by Hutubessy et al. in Tanzania , these decreased by 37% due to a change in the number of doses of HPV vaccines and a lower percentage of vaccinations taking place at schools. That is, the WHO recommended number of vaccine doses per girl has declined from three to two , leading to lower projected costs for procurement. In addition, in the 2012 study, it was assumed that all vaccines would be given at schools while this study assumes that approximately half of the target population would be vaccinated in health facilities and the other half in schools, leading to lower service delivery costs. Other projected costs have increased in this study, e.g. the cost per service delivery visit has increased due to higher per diems and travel allowances.
The projected financial annual costs of cervical cancer screening and treatment range from $8.0 million in 2020 to $11.4 million in 2024 while projected economic annual costs range from $13.1 million in 2020 to $17.5 million in 2024. The service with the highest share of costs is screening (combination of VIA and HPV-DNA testing) since the projected service volume is significantly higher than that for pre-cancer and cancer services even though the latter costs per service are much higher. Programmatic costs also comprise a large share, i.e. 16.3% and 25.6% for financial and economic costs, respectively.
To understand the context of implementing cervical cancer prevention and control in Tanzania, the proportion of the annual health budget that would be required to finance the programme was calculated. The estimated proportion of the annual 2020/2021 health budget of Tanzania  that would be required is 1.4%, and this suggests that a comprehensive prevention and control programme is likely to be affordable.
The costs of screening and treatment are similar to those found in other studies in low- and lower-middle-income countries. The cost of a woman screened with VIA in other studies US$3.33  to US$3.67  compares well with US$3.66 to US$5.44 in this study. The cost of a woman screened with HPV-DNA testing in other studies [US$6.27 to US$15.92]  is in the range of this study’s estimates [US$9.20 to US$10.03]. The estimate of a cryotherapy service in this study, US$5.14 to US$7.21, is lower, however, than in other studies, e.g. US$38  or US$28.97 , possibly because the costs of equipment were calculated differently, i.e. these were divided by total national expected cases rather than by the number of cases referred to tertiary or referral hospitals. The costs of cancer services in this study, though, are similar to those found in Nelson et al. .
This study has some limitations. The first limitation of our study is that we illustrated the application of the C4P tool based only on the Tanzania Strategic Plan Cervical Cancer Prevention and Control , which had been developed before new WHO guidelines for cervical cancer prevention and control had been published. The C4P tool has the capability of comparing scenarios and could potentially have been used to calculate the costs of relevant alternative strategies such as 1-dose HPV vaccine regimes, self-collected samples for HPV testing and thermal ablation. The second limitation relates to the short 5-year study period of the C4P tool, which reflects its emphasis on programme management rather than policymaking. The impact of vaccination is realized only in the longer term, and so the significant cost savings of reductions in treatment for pre-cancer and for down-staged invasive cancer are not captured by the tool. The third limitation is that data collection did not include the sampling of health facilities due to the limited time frame and budget for the study. A final limitation of the C4P tool is that a formal uncertainty or sensitivity analysis is not included in the tool itself.
If Tanzania can scale up these services for the prevention and control of cervical cancer, there will be an important impact on cervical cancer morbidity and mortality over the medium and long term. The impact, though, will be affected by whether there is compliance with referrals and accurate diagnoses and effective treatment. So, it will be important during the scale-up not only to focus just on increasing the number of sites that provide services but also to ensure the quality of services. It will also be important to ensure the equity of service provision and access to screening and pre-cancer services at lower levels of the health system.