The Nairobi Urban Health and Demographic Surveillance System (NUHDSS) was set up in 2002 in two Nairobi informal settlements (Korogocho and Viwandani) to provide a platform for investigating linkages between urban poverty, health, and demographic and other socioeconomic outcomes, and to facilitate the evaluation of interventions to improve the wellbeing of the urban poor. All households are visited every four months to collect demographic and health information. The present module refers to 'Outmigration'.
Two informal settlements (slums) in Nairobi county, Kenya (specifically, Korogocho and Viwandani slums).
Unit of Analysis
The survey covers all the households in the DSA
Producers and sponsors
Authoring entity/Primary investigators
African Population and Health Research Center
Rockefeller Foundation (USA)
William and Flora Hewlett Foundation (USA)
Comic Relief (UK)
Swedish International Development Cooperation
The Bill and Melinda Gates Foundation (USA)
Residents of Korogocho and Viwandani Slums
Community leaders - chiefs and village elders
Support to field teams
Dates of Data Collection (YYYY/MM/DD)
Round 2, Round 3 and Round 4
Round 5, Round 6 and Round 7
Round 8, Round 9 and Round 10
Round 11, Round 12 and Round 13
Round 14, Round 15 and Round 16
Round 17 and Round 18
Round 19, Round 20 and Round 21
Round 22, Round 23 and Round 24
Round 25, Round 26 and Round 27
Round 28, Round 29 and Round 30
Round 31 and Round 32
Round 33, Round 34 and Round 35
Round 37 and Round 38
Mode of data collection
Interviewing teams in the two sites of study comprised of:
- Korogocho: 1 field supervisor, 2 editting team leaders, 1 data quality control team leader, 1 deaths' monitoring team leader, 2 data quality control officers, 12 interviewers
- Viwandani: 1 field supervisor, 2 editting team leaders, 1 data quality control team leader, 1 deaths' monitoring team leader, 3 data quality control officers, 17 interviewers
The roles of the various members of the interviewing teams were:
- Interviewer: Conducting face-to-face paper-based interviews(Round 0- Round 38) and using Netbooks (Round 39 onwards) in assigned zone within the study site
- Data Quality Control Officer: Performing random spot-checks on 10% of the questionnaires and reporting inconsistencies to the Data Quality Control Team Leader for harmonization
within the study community
- Data Quality Control Team Leader: Harmonizing inconsistencies within questionnaires and performing a random spot-check on 10% of the 10% questionnaires that have already undergone spot-checking
- Editting Team Leader: Editting 100% of questionnaires from randomly selected field workers and documenting issues emerging during data collection
- Field supervisor: Responsible for overseeing general operations, resolving issues that cannot be harmonized by data quality control and ensuring that field work progressed on schedule. They also conducted sit-in interviews along with Data Quality Control Team Leader
The Field Co-ordinator, Research Officer and/or Project Managers visited the field and field teams regularly to monitor and review progress and support field operations.
Type of Research Instrument
1. Outmigration registration form
Data editing took place at a number of stages throughout the processing, including:
1. Quality control through back-checks on 10 percent of completed questionnaires and editing of all completed questionnaires by supervisors and project management staff.
2. A quality control officer performed internal consistency checks for all questionnaires and edited all paper questionnaires coming from the field before their submission for data entry with return of incorrectly filled questionnaires to the field for error-resolution.
3. During data entry, any questionnaires that were found to be inconsistent were returned to the field for resolution.
4. Data cleaning and editting was carried out using STATA Version 13 software.
Data were entered as follows:
1. Typed based on paper questionnaires at APHRC's headquarters on desktop computers. Double data entry was carried out on 10% of the questionnaires (Round 0- Round 38).
2. Using Netbooks (Round 39 onwards).
In both cases, data were captured using in-house software developed with a Visual Basic. Net front-end and a Microsoft Structured Query Language (SQL) Server back-end.
Director of Research
All non-APHRC staff seeking to use data generated at the Center must obtain written approval to use the data from the Director of Research. This form is developed to assess applications for data use and facilitate responsible sharing of data with external partners/collaborators/researchers. By entering into this agreement, the undersigned agrees to use these data only for the purpose for which they were obtained and to abide by the conditions outlined below:
1. Data Ownership: The data remain the property of APHRC; any unauthorized reproduction and sharing of the data is strictly prohibited. The user will, therefore, not release nor permit others to use or release the data to any other person without the written authorization from the Center.
2. Purpose: The provided data must be used for the purpose specified in the Data Request Form; any other use not specified in the form must receive additional or separate authorization.
3. Respondent Identifiers: The Center is committed to protecting the identity of the respondents who provide information in its research. All analytical data sets (both qualitative and quantitative) released by the Data Unit MUST are stripped of respondent identifiers to protect the identity of the respondents. By accepting to use APHRC data, the user is pledging that he/she will not, under any circumstance, regenerate the identifiers or permit others to use the data to learn the identity of any individual, household or community included in any data set.
4. Confidentiality pledge: The user will not use nor permit others to use the data to report any information in the data sets that could identify, directly or by inference, individuals or households.
5. Reporting of errors or inconsistencies: The user will promptly notify the Head of the Statistics and Survey Unit any errors discovered in the data as soon as the errors are discovered.
6. Publications resulting from APHRC data: The Center requires external collaborators to work with APHRC staff on all publications resulting from its data. In order to facilitate this, lead authors should send a detailed concept note of the paper (including the background, rationale, data, analytical methods, and preliminary findings) to the Principle Investigator (or Theme Leader) for the project (with a copy to the Director of Research), who will circulate the abstract to concerned researchers for possible expression of interest in participating in the publication as co-authors. Any exception to the involvement of APHRC staff should be approved by the Director of Research, APHRC.
7. Security: The user will take responsibility for the security of the data by ensuring that the data are used and stored in a secure environment where access is password protected. This will ensure that non-authorized people should not have access to the data.
8. Loss of privilege to use data: In the event that APHRC determines that the data user is in violation of the conditions for using the data, or if the user wishes to cancel this agreement, the user will destroy the data files provided to him/her. APHRC retains the right to revoke this agreement or informs publishers to withhold publication of any work based wholly or in part on its data if the conditions for using the data are violated.
9. Acknowledgement: Any work/reports from this data must acknowledge APHRC as the source of these data. For example, the suggested acknowledgement for NUHDSS data is:
"This research uses livelihoods data collected under the longitudinal Nairobi Urban Health and Demographic Surveillance System (NUHDSS) since 2006. The NUHDSS is carried out by the African Population and Health Research Center in two slums settlements (Korogocho and Viwandani) in Nairobi City."
Additionally all funders, the study communities that provided the data, and staff who collected and analyzed or processed the data should be acknowledged.
10. Deposit of Reports/Papers: The user should submit electronic and paper copies of all publications generated using APHRC data to the Policy Engagement and Communications Department, with copies to the Director of Research.
11. Change of contact details: The user will promptly inform the Director of Research of any change in your personal details as contained on this data request form.
African Population and Health Research Center (APHRC), Nairobi Urban Health and Demographic Surveillance System - Outmigration registration 2002-2015, Version 1.0 June 2017. doi:10.20369/aphrc-038:2003.1.01
Disclaimer and copyrights
The user of the data acknowledges that APHRC and the relevant funding agency bear no responsibility for use of the data or for interpretations or inferences based upon such uses.