Study Design

ABC-DO is a multi-country observational study to prospectively estimate breast cancer survival and investigate its proximal and distal determinants in sub-Saharan Africa. The primary outcome will be vital status, i.e. survival after breast cancer diagnosis, and secondary outcomes will include patient-reported assessment of health and well-being, treatment compliance, and time to treatment. Over a 2-year period of enrolment, about 1800 women newly diagnosed with breast cancer at four public hospital settings in sub-Saharan Africa (see Settings) will be invited to participate in the study. At the first visit where breast cancer is suspected, the woman will be interviewed by a study nurse to obtain information on breast cancer risk factors, social, cultural, and economic factors, access to health care, health knowledge and beliefs, and health-seeking behaviour. The study nurse will also obtain the clinical and treatment data during the woman's period of treatment. At 3-monthly intervals for up to 3 years, the study nurse will telephone the woman or her next of kin to obtain data on vital status, treatment side-effects, treatment compliance, and health status and possible barriers to health-care utilization and treatment adherence. A specific effort is being made to reduce losses to follow-up as this has been a major drawback of previous studies. To achieve this, an integral methodological component is the use of mobile technologies for data capture at diagnosis, during clinical care and for follow-up.

ABC-DO is being conducted in four public hospital settings in South Africa, Namibia, Uganda, and Nigeria. In all settings, patients are predominantly from the public sector and are black African women. No population-based mammographic screening is conducted in the source populations, and each hospital manages a large breast cancer patient load per year (>200). While achieving representativeness for the public sector, the settings have been selected to generate heterogeneity in the major factors that are hypothesized to affect breast cancer survival in this population. The settings span countries at different stages of the breast cancer transition. They include geographically proximate as well as disparate catchment populations, hospitals with and without free provision of diagnosis and treatment, those where immunohistochemistry for receptors is routinely conducted and not routinely conducted, and some with support services such as free hospital transportation and associations providing free accommodation during treatment regimes. The sites are: