Dikgale HDSS INDEPTH Core Dataset 1996 - 2014 (Release 2017)

Changes in socio-economic status and lifestyle behaviors among the adult population in South Africa not only in urban areas but also in rural South Africa, have led to increased prevalence of chronic diseases and associated risk factors, together with an epidemic of some infectious diseases. Researchers at the University of the North (now University of Limpopo Turfloop campus) established The Dikgale centre for Health and Demographic surveillance system in 1996 funded by a core grant from NUFU, Norway.

The broad aim of the Dikgale HDSS is to provide information to improve health of the people in Limpopo province and to assist the local government in making effective health care policy. As few data are available on the prevalence of diseases in rural and peri-urban areas of Limpopo province, the initial objective of the HDSS was to establish a field site where the incidence and prevalence of diseases could be assessed. It was therefore necessary to collect longitudinal demographic data (e.g. mortality, fertility, migration) on the population. To this end, three primary subjects are observed longitudinally in Dikgale HDSS: physical structures (e.g. homesteads, clinics and schools), households and individuals. The information about these subjects, and all related information, was at first stored in Access and later in a single MSSQL Server database, in a truly longitudinal way-i.e. not as a series of cross-sections.

The surveillance area is located in the Capricorn district, Limpopo province approximately 40 km from Polokwane, the capital city of Limpopo province and 15-50 km from the University of Limpopo (Turfloop campus). The site covers an area of approximately 200 square kilometers. The initially the total population was 8000 but the field site was expanded in 2010 and now includes approximately 36,000 people who are members of approximately 7000 households. The households are present in 15 villages of varying sizes. The population is predominantly Northern Sotho speaking. All households have electricity. Some households have piped water either inside the house or in their yards, but most fetch water from taps situated at strategic points in the villages. Most households have a pit latrine in their yards. A large proportion of adults are migrant workers, while others work as farm laborers on neighboring farms, or as domestic workers in nearby towns. Many are pensioners. The unemployment rate in the area is high.

To fulfil the eligibility criteria for the Dikgale HDSS cohort, individuals must be a member of a household within the surveillance area but not necessarily resident within it. Crucially, this means that Dikgale HDSS collects information on resident and non-resident members of households and makes a distinction between membership (self-defined on the basis of links to other household members) and residency (residing at a physical structure within the surveillance area at a particular point in time). Individuals can be members of more than one household at any point in time (e.g. polygamous married men whose wives maintain separate households). To be consistent with similar datasets from other INDEPTH Member centres, this data set contains data from resident members only.

During data collection, households are visited by fieldworkers and information supplied by a single key informant. All births, deaths and migrations of household members are recorded. If household members have moved internally within the surveillance area, such moves are reconciled and the internal migrant retains the original identifier associated with him/her.