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SAMPLING AND HOUSEHOLD LISTING MANuaL Demographic and Health Surveys Methodology This document is part of the Demographic and Health Survey’s DHS Toolkit of methodology for the MEASURE DHS Phase III project, implemented from 2008-2013. This publication was produced for review by the United States Agency for International Development (USAID). It was prepared by MEASURE DHS/ICF International. [THIS PAGE IS INTENTIONALLY BLANK] Demographic and Health Survey Sampling and Household Listing Manual ICF International Calverton, Maryland USA September 2012 MEASURE DHS is a five-year project to assist institutions in collecting and analyzing data needed to plan, monitor, and evaluate population, health, and nutrition programs. MEASURE DHS is funded by the U.S. Agency for International Development (USAID). The project is implemented by ICF International in Calverton, Maryland, in partnership with the Johns Hopkins Bloomberg School of Public Health/Center for Communication Programs, the Program for Appropriate Technology in Health (PATH), Futures Institute, Camris International, and Blue Raster. The main objectives of the MEASURE DHS program are to: 1) provide improved information through appropriate data collection, analysis, and evaluation; 2) improve coordination and partnerships in data collection at the international and country levels; 3) increase host-country institutionalization of data collection capacity; 4) improve data collection and analysis tools and methodologies; and 5) improve the dissemination and utilization of data. For information about the Demographic and Health Surveys (DHS) program, write to DHS, ICF International, 11785 Beltsville Drive, Suite 300, Calverton, MD 20705, U.S.A. (Telephone: 301-572- 0200; fax: 301-572-0999; e-mail: [email protected]; Internet: http://www.measuredhs.com). Recommended citation: ICF International. 2012. Demographic and Health Survey Sampling and Household Listing Manual. MEASURE DHS, Calverton, Maryland, U.S.A.: ICF International TABLE OF CONTENTS TABLES AND FIGURES ......................................................................................................... vii 1 DEMOGRAPHIC AND HEALTH SURVEYS SAMPLING POLICY ........................................ 1 1.1 General principles ............................................................................................ 1 1.1.1 Existing sampling frame ......................................................................... 1 1.1.2 Full coverage ........................................................................................ 1 1.1.3 Probability sampling .............................................................................. 2 1.1.4 Suitable sample size .............................................................................. 2 1.1.5 Simple design ....................................................................................... 2 1.1.6 Household listing and pre-selection of households ...................................... 2 1.1.7 Good sample documentation ................................................................... 2 1.1.8 Confidentiality ...................................................................................... 3 1.1.9 Exactness of survey implementation ........................................................ 3 1.2 Survey objectives and target population .............................................................. 3 1.3 Survey domain ................................................................................................ 4 1.4 Sampling frame ............................................................................................... 4 1.4.1 Conventional sampling frame .................................................................. 5 1.4.2 Alternative sampling frames ................................................................... 5 1.4.3 Evaluation of the sampling frame ............................................................ 6 1.5 Stratification ................................................................................................... 6 1.6 Sample size .................................................................................................... 7 1.6.1 Sample size and sampling errors ............................................................. 7 1.6.2 Sample size determination ....................................................................10 1.7 Sample allocation ............................................................................................12 1.8 Two-stage cluster sampling procedure ...............................................................15 1.9 Sample “take” per cluster .................................................................................16 1.9.1 Optimum sample take ...........................................................................16 1.9.2 Variable sample take for self-weighting ...................................................17 1.10 Household listing ............................................................................................19 1.11 Household selection in the central office .............................................................20 1.12 Household interviews .......................................................................................21 1.13 Sampling weight calculation ..............................................................................22 1.13.1 Why we need to weight the survey data ..................................................22 1.13.2 Design weights and sampling weights .....................................................22 1.13.3 How to calculate the design weights ........................................................23 iii 1.13.4 Correction of unit non-response and calculation of sampling weights............ 24 1.13.5 Normalization of sampling weights ..........................................................26 1.13.6 Standard weights for HIV testing ............................................................27 1.13.7 De-normalization of standard weights for pooled data................................ 28 1.14 Calibration of sampling weights in case of bias ....................................................29 1.15 Data quality and sampling error reporting ...........................................................30 1.16 Sample documentation ....................................................................................31 1.17 Confidentiality ................................................................................................31 2 HOUSEHOLD LISTING OPERATION ........................................................................... 32 2.1 Introduction ...................................................................................................32 2.2 Definition of terms ..........................................................................................32 2.3 Responsibilities of the listing staff ......................................................................33 2.4 Locating the cluster .........................................................................................34 2.5 Preparing location and sketch maps ...................................................................35 2.6 Collecting a GPS waypoint for each cluster ..........................................................36 2.7 Listing of households .......................................................................................37 2.8 Segmentation of large clusters ..........................................................................38 2.9 Quality control ................................................................................................39 2.10 Prepare the household listing forms for household selection ..................................39 Appendix 2.1 Example listing forms .............................................................................41 Appendix 2.2 Symbols for mapping and listing ..............................................................46 Appendix 2.3 Examples of completed mapping and listing forms ......................................48 3 SELECTED SAMPLING TECHNIQUES ......................................................................... 52 3.1 Simple random sampling ..................................................................................52 3.2 Equal probability systematic sampling ................................................................53 3.2.1 Sampling theory ..................................................................................53 3.2.2 Excel templates for systematic sampling ..................................................55 3.3 Probability proportional to size sampling .............................................................64 3.3.1 Sampling theory ..................................................................................64 3.3.2 Operational description and examples .....................................................65 3.4 Complex sampling procedures ...........................................................................70 4 SURVEY ERRORS ...................................................................................................... 73 4.1 Errors of coverage and non-response .................................................................73 4.1.1 Coverage errors ...................................................................................73 4.1.2 Deliberate restrictions of coverage ..........................................................74 4.1.3 Non-response ......................................................................................74
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