Mbita Health and Demographic Surveillance System core Dataset 2009-2011
Rounds 1 to 25
The Mbita Health and Demographic Surveillance System (Mbita HDSS), located on the shores of Lake Victoria in Kenya, was established in 2006. The main objective of the HDSS is to provide a platform for population-based research on relationships between diseases and socio-economic and environmental factors, and for the evaluation of disease control interventions.
The Mbita HDSS had a population of approximately 54 014 inhabitants from 11 576 households in June 2013. Regular data are collected using personal digital assistants (PDAs) every 3 months, which includes births, pregnancies, migration events and deaths. Coordinates are taken using geographical positioning system (GPS) units to map all dwelling units during data collection. Cause of death is inferred from verbal autopsy questionnaires. In addition, other health-related data such as vaccination status, socio-economic status, water sources, acute illness and bed net distribution are collected.
The HDSS has also provided a platform for conducting various other research activities such as entomology studies including malaria research on neglected tropical diseases, and environmental health projects which have benefited the organization as well as the HDSS community residents. Data collected are shared with the community members, health officials, local administration and other relevant organizations. Opportunities for collaboration and data sharing with the wider research community are available and those interested should contact email@example.com <mailto:firstname.lastname@example.org> or email@example.com <mailto:firstname.lastname@example.org>.
Kind of Data
Event history data
Unit of Analysis
Version 01: First version for internal use
Version 03: Edited dataset for public distribution
Developed during iSHARE 2 workshop
The Scope of demographic surveillance includes demographic characteristics, households, living conditions, social security, access to facilities and services, hygiene, education levels, employment status, migration, fertility, mortality, etc.
- Household: Household characteristics, household listing, occupation, education and maternal mortality.
- Individual: Individual listing, education, occupation, marital status and movements.
- Women: Pregnancy monitoring
Mbita HDSS covers part of the western Kenya near the shores of the Lake Victoria including Rusinga Island(North Part) and mainland labeled as Gembe in Gembe location(South Part). Area coverage is about 168KM square.
The area is accessible by a ferry through the Lake victoria to the mainland of Lwanda Kotieno in Kisumu area of Kisumu County. There is also a tarmack road connection that goes through the mainland from the Homabay County to Mbita HDSS area and it is linked to the man-made bridge that links the the mainland to Rusinga Island.
All individuals in the HDSS survey area.
Producers and sponsors
Nagasaki University Insititute of Tropical Medicine
Collaborative partnership with the Kenya Medical Research Institute
Prof. M. Shimada
Team - Leader
Prof. M. Karama
Deputy Team Leader
Prof. S. Kaneko
Ms. S. Wanyua
Mr. M. Ndemwa
Government of Japan
Nagasaki University Institute of Tropical Medicine
Project Leadership and Technical Support
Kenya Medical Research Institute
Partnership affiliation and Technical Support
Partnership and cooperation in data collection
Devolved governmennt system (Homabay county)
Partnership and cooperation in data collection
Response rate is about 95%.
Dates of Data Collection
Frequency of Data Collection
At-least 4 rounds per year
Data Collection Mode
Enumerators (field interviewers) were organized in teams per working areas and regions which they are assigned to all interviwers. All enumarators report to a supervisor(field interviewer manager) who is assigned about 6 enumarators and he/she is able to manage them by using an assigned motorbike to move from one working area to the other. The field interviewer manager (supervisor) roles include the following: coordinate data collection, supplies of equipment and gadgets, coordinating with local authorities, quality assuarance report including checking empty houses/structures, conducting verbal autopsy after the mourning period has passed and following up on skipped houses which may have been skipped by enumarotors if for some reasons owners were absent or only minors were available during the visit.
The data manager at the field station was responsible for the transfer of collected data to our remote server for cleaning before synchronization of the data and backup. The data manager would go through the quality check reports generated automatically by the system and assignes duties to field interviewer manager based on the results for updates and corrections.
Upper management from the (Nairobi) managing the core data set visited the field once every month and after every round had been completed.
Data Collection Notes
Training of enumerators (known as filed interviewres in Mibita HDSS site) is routinely done before the start of any new round.
This is usually done to familiarize with the system updates on the programme or any additional changes that may seem necessary and necessitate smooth running of the data collection criteria or inform the enumarotors of the anychanges that they may have suggested for the smooth running of data collection process.
- Usually interview may take about 30mins to about 45mins depending on whether there were any additional questionaires added to their routine data collection method.
- Community mobilization and sensitization was first done before data collection at the baseline.
- In addition, more involvement was done to inform community leaders especially the chiefs, leaders and community heads (including policy makers) of the objectives of the HDSS programe.
- The data collection team has usually been conducted by field interviewers (FI) 17 in number guided by immediate supervisors that are named as field interviewer manager (FIM) who are 3 in number.
- Supervisory team comprising of a data manager at the field station and an asdministrator would oversee the whole process and they may seek intervention by community leaders in areas where the community may not seem intrested or refusing to accept enumaration.
- Interview is normally done in local language (Luo) or in Swahili where there find in-migrants.
The questionnaire is divided into several parts. The 1st part consists of the baseline census dealing mainly with demographic information, such as compounds, household and members. The second part is made up of questions on migrations, health, diseases, causes of death, and other health and hygiene related information.
These processes are repeated to accumulate demographic and health related information for several years.
Data collection in the field uses electronic devices pda. These devises support field interviewers' data collection activities and execute data consistency checks with regard to questionnaire items on site.
Assumed variables of questionnaire are:
ø information for individual identification
ø demographic information
ø household information
ø migration information
ø pregnancy information
ø health related information
ø vital event information
Collected data is accumulated in the field stations and sent to data management centre in the central office in nairobi, and are subjected to detail-verification check by data managers. If inconsistent data or unverified data are detected, those data and error codes (or explanation) are sent back to the field.
Verbal Autopsy Questionaires design was made with some modifications but adapted from the recommended WHO questionnaire.
Data management is conducted on PDA, Station PC and main server database.
For quality control, several error check programmes were installed, for the following purposes: range checks, entry missing checks, inter-variable checks, consistency check between currently entered data and past data, etc.
Data was left censored to 1 Jan 2009 to account for the start-up phase of the surveillance.
This data is anonymised and no confidentiality agreement in addition to the general data use agreement is required.
1. Data and other material provided by INDEPTH will not be redistributed or sold to other individuals, institutions or organisations without INDEPTH's written agreement.
2. Data originating from a single contributing member centre of the INDEPTH Network may not be analysed or reported on in isolation without the express permission of the member centre concerned.
3. No attempt will be made to re-identify respondents, and there will be no use of the identity of any person or establishment discovered inadvertently. Any such discovery will be reported immediately to INDEPTH.
4. No attempt will be made to produce links between datasets provided by INDEPTH or between INDEPTH data and other datasets that could identify individuals.
5. Any books, articles, conference papers, theses, dissertations, reports or other publications employing data obtained from INDEPTH will cite the source, in line with the citation requirement provided with the dataset.
6. An electronic copy of all publications based on the requested data will be sent to INDEPTH.
7. The original collector of the data, INDEPTH, and the relevant funding agencies bear no responsibility for the data's use or interpretation or inferences based upon it.
Any use of this dataset must cite the digital object identifier (doi) associated with this dataset. Using the following form:
"The Mbita HDSS Core Micro Data Set 2009-2011. March 2014. Provided by the INDEPTH Network Data Repository. www.indepth-network.org <http://www.indepth-network.org>. 10.7796/INDEPTH.KE041.CMD2011.v3 <http://dx.doi.org/10.7796/INDEPTH.KE041.CMD2011.v3>"
INDEPTH Data Repository
Disclaimer and copyrights
The user of the data acknowledges that the original collector of the data, INDEPTH, and the relevant funding agencies bear no responsibility for the data's use or interpretation or inferences based upon it.
DDI Document ID
Documentation of the study
iSHARE2 Technical Team
Date of Metadata Production
DDI Document version
Edited version, the original DDI (DDI.INDEPTH.KE041.CMD2011.V6) was downloaded from INDEPTH Data Repository (http://www.indepth-ishare.org/index.php/catalog/central) on October 2014. The following DDI elements have been modified: DDI Document ID, survey ID and title of the study.