Notes on Data Collection:
The field team supervisors were trained for four days prior to the main enumerator training. The field staff was trained in Morogoro in September 2014 over a period of three weeks with enumerator and data entry training done concurrently. During a standard training week, four days were spent in classroom, and one day in field training. On each Saturday of the training month, the field staff was debriefed on the previous day’s field exercise and what they had learned over the previous week. Over the three week training period, the field staff spent one week on the Household Questionnaire, and a week and a half on the Agricultural Questionnaire, Livestock/Fishery Questionnaire, and tracking. The last three days of the training were devoted to field practice. Select households from an MCAT survey conducted in 2010 were revisited to provide the team supervisors practice with conducting tracking during fieldwork. After the pilots, extensive discussion and revisions were conducted with the participation of all team supervisors.
Over the training period, three tests were administered to the field teams. The goal was to gain feedback from the training sessions and to select the enumerators. Overall, there were 55 enumerator candidates, with 48 being selected. Interviewer manuals were developed with detailed instructions for field staff during training and as the main reference guide for the survey over the course of the fieldwork. At the end of the training, the enumerators were each provided with an interviewer manual in Kiswahili.
The main data collection began in October 2014 and finished in October 2015, with tracking fieldwork continuing until the end of January 2016. The survey was primarily implemented by eight mobile field teams, each composed of: one supervisor, five or six enumerators, one data entry technician, and one driver. Seven mobile field teams were responsible for different regions on the mainland and one team was responsible for all of Zanzibar.
Field teams visited each cluster for three to four days. The questionnaires were administered to the selected households over the course of that time. This allowed the field team to make return visits to the household to complete the entire Household Questionnaire, Agriculture Questionnaire for farming households, and Livestock & Fisheries Questionnaire for households engaged in livestock or fisheries activities. To ensure the depth and quality of each section of the survey, the questionnaire was administered across multiple respondents to the most knowledgeable about each topic. For all of the sampled households, areas of all owned and/or cultivated agricultural plots were measured via GPS unless the household refused, the terrain was too difficult, or if the plot was more than one hour from the location of the household. Anthropometric measurements were taken for all individuals that were at home, not too ill, and willing to participate.
When the field teams enter a new cluster, they listed all of the households within the boundaries of the EA. This consisted of collecting basic information on the households in the EA, including name of head of household, contact information, and size of household. After all the households in the EA had been listed, the information was then entered into a data entry program in CSPro. Total listing household counts where compared with previous census counts and when significant variation existed, listing accuracy was confirmed. After all the information has been entered, the application would then select with systematic random selection and report eight households in the EA to be interviewed by the team. The application additionally provided three randomly selected replacement households.
Data Processing & Management:
The NPS 2014/2015 contains a robust, multi-level quality assurance and data management system. Great effort was placed on the development and utilization of this system by the NBS, with technical assistance from the World Bank, to assist in the management of the complex household panel survey and address the growing need for high quality timely data.
The NPS utilizes a concurrent field entry system known as CAFE, or Computer Assisted Field Entry. This system was selected to increase the availability of data for review by managing staff as well as to provide regular and consistent quality assessment of data directly to the field staff. As with the earlier rounds, CSPro was used for data entry and initial quality reporting while STATA was utilized to perform complex aggregated checks. Building off of the work conducted for the NPS 2010/2011 and NPS 2012/2013, the NPS 2014/2015 data entry application further develops the quantity and complexity of data quality checking routines while simplifying reporting. Furthermore, due to the panel nature of the survey, where applicable and appropriate, data was checked against data from previous rounds.
As data entry took place while in the interview area, when data issues were identified and reported the field teams would return to households and clarify and correct inconsistent information prior to the transmission of the data to headquarters. Data files from completed clusters were transmitted to NBS headquarters via syncing to a server using 3G USB modems. Received data files were concatenated at the headquarters, and regular checks were performed to ensure the fieldwork was proceeding according to the schedule and that quality standards were met. During the course of field work, data was routinely checked at the aggregate level to identify any potential issues and, where identified, additional checks where integrated into the CAFE system.
Throughout the course of field work, the field teams regularly sent the paper questionnaires back to the NBS headquarters for further processing. Once the paper questionnaires and data files for completed EAs were received at NBS headquarters, a double-entry procedure was implemented. Six data entry operators were hired by NBS to perform the second data entry for the paper questionnaires into the CSPro-based data entry system for all questionnaires administered. A comparison between the entered values in the field based data entry and headquarters based data entry was conducted and any discrepancies in values between the two were flagged for manual inspection of the physical questionnaire and corrected. The application of the third level of data consistency validation further allowed for the assessment of the quality of the entry work performed by both the field entry staff and the headquarters based entry staff. Regular feedback was supplied to data entry staff resulting in improved quality where needed and overall efficiency.