UPHD - Migration and Employment History for Pre-Selected Individuals Aged 12 and plus
The Migration and Employment History Survey was part of the 5 themes of the Urbanization, Poverty and Health Dynamics I (UPHD I) Project in Sub-Saharan Africa. The UPHD I project was designed and implemented by APHRC. The Migration and Employment History Survey was designed to investigate patterns and reasons for migration among residents in Nairobi's informal settlements, the linkages between migration, livelihood conditions, and health status.
This theme investigated patterns and reasons for migration, the linkages between migration, livelihood conditions, and health status among pre-selected individuals aged 12+ from 2006 to 2010 in Nairobi's informal settlements.
The specific objectives were to:
1.1 Determine the characteristics of in- and out-migrants, their migration histories, reasons for migrating, and nature of links with origin communities;
1.2 Investigate how changing poverty and health circumstances influence and are influenced by intra-urban and urban-rural migrations;
1.3 Assess the motivations for migration (e.g. health-related reasons) and how this has an influence on estimates of mortality and fertility levels in informal settlements;
1.4 Validate the relevance of various measures of poverty in informal urban settlements.
Kind of Data
Sample survey data [ssd]
v1.0: Edited, anonymous dataset for Data Documentation Working Group
v1.1: Edited, anonymous dataset for Researcher Review
v1.2: Edited, anonymous dataset incorporating the Researchers' Comments and changing variable names to the corresponding question number
v1.3: Edited, anonymous dataset with data-sharing links moved from Technical Documents to Access Policy
Version 1.4, November 2014. Anonymized with DOI and Recommended Citation added.
Two informal settlements, Korogocho and Viwandani, in Nairobi City (the capital city) of Kenya.
Unit of Analysis
The unit of analysis is the individual
The survey covered all de jure household members (usual residents), aged 12 and above in the household
Producers and sponsors
Authoring entity/Primary investigators
African Population & Health Research Center
Eliya Zulu, PhD
Nyovani Madise, PhD
Alex Ezeh, PhD
John Cleland, PhD
Jane Falkingham, PhD
Jean-Christophe Fotso, PhD
Zewdu Woubalem, PhD
Residents of Korogocho and Viwandani Slums
Korogocho and Viwandani
Information were collected from a random panel sample of close to 8,200 households from the two sites (5,200 in Viwandani and 3,000 in Korogocho). These households would yield about 6400 and 9000 people aged at least 12 years in Korogocho and Viwandani, respectively.
Sample weights were not used.
Dates of Data Collection (YYYY/MM/DD)
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, 2 data quality control officers, 12 interviewers
- Viwandani: 1 field supervisor, 2 editting team leaders, 1 data quality control 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 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
- 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
The questionnaire used was one structured questionnaire, Migration and Employment History Form. It includes: Background characteristics, Respondents' characteristics, Migration and Livelihood Calendar, Timing of current and 1st migration to Nairobi, and Individual Income-Generating Activities.
All questionnaires are provided as external resources.
African Population & Health Research Center
Data editing took place at a number of stages throughout the processing, including:
a) Office editing and coding
b) During data entry
c) Structure checking and completeness
d) Secondary editing
e) Structural checking of STATA data files
Detailed documentation of the editing of data can be found in the "Standard Procedures Manual" document provided as an external resource.
Some corrections are made automatically by the program (80%) and the rest by visual control of the questionnaire (20%).
Where changes are made by the program, a cold deck imputation is preferred; where incorrect values are imputed using existing data from another dataset. If cold deck is found to be insufficient, hot deck imputation is used. In this case, a missing value is imputed from a randomly selected similar record in the same dataset.
Data entry was performed manually at APHRC's headquarters on desktop computers and was done using an in-house built system with a Visual Basic.Net front-end and a Microsoft SQL Server back-end. Double data entry was carried out on 10% of the questionnaires.
Data were processed in clusters, with each cluster being processed as a complete unit through each stage of data processing. Each cluster goes through the following steps:
1) Questionnaire reception
2) Office editing and coding
3) Data entry
4) Structure and completeness checking
5) Verification entry
6) Comparison of verification data
7) Back up of raw data
8) Secondary editing
9) Edited data back up
After all clusters are processed, all data is concatenated together and then the following steps are completed for all data files:
10) Export to STATA 10 in 2 files (migration & employment history, migration & employment calendar)
11) Recoding of variables needed for analysis
13) Structural checking of STATA 10 files
14) Data quality tabulations
15) Production of analysis tabulations
Details of each of these steps can be found in the Standard Procedures Manual.
Estimates of Sampling Error
No estimation of sampling error was done.
This is accomplished in the following ways:
- Comparison of our indicators to other indicators, e.g. DHS
- Comparing trends from one survey year to the next
African Population & Health Research Center
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. This statement does not replace a more comprehensive data agreement (see External Resources)
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:
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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, Urbanization, Poverty and Health Dynamics - Migration and Employment History Survey, July 2011. APHRC, Nairobi - Kenya. doi:11239/176-2006-011-1.4
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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.
(c) 2011, African Population & Health Research Center (APHRC)