The 1993 Ghana Demographic and Health Survey (GDHS) is a nationally representative survey of 4,562 women age 15-49 and 1,302 men age 15-59. The survey is designed to furnish policymakers, planners and program managers with factual, reliable and up-to-date information on fertility, family planning and the status of maternal and child health care in the country. The survey, which was carried out by the Ghana Statistical Service (GSS), marks Ghana's second participation in the worldwide Demographic and Health Surveys (DHS) program.
The principal objective of the 1993 GDHS is to generate reliable and current information on fertility, mortality, contraception and maternal and child health indicators. Such data are necessary for effective policy formulation as well as program design, monitoring and evaluation. The 1993 GDHS is, in large measure, an update to the 1988 GDHS. Together, the two surveys provide comparable information for two points in time, thus allowing assessment of changes and trends in various demographic and health indicators over time.
Long-term objectives of the survey include (i) strengthening the capacity of the Ghana Statistical Service to plan, conduct, process and analyze data from a complex, large-scale survey such as the Demographic and Health Survey, and (ii) contributing to the ever-expanding international database on demographic and health-related variables.
Kind of data
Sample survey data
Unit of analysis
- Children under five years
- Women age 15-49
- Men age 15-59
Producers and sponsors
Ghana Statistical Service (GSS)
Macro International Inc.
United States Agency for International Development
The 1993 GDHS is a stratified, self-weighting, nationally representative sample of households chosen from 400 Enumeration Areas (EAs). The 1984 Population Census EAs constituted the sampling frame. The frame was first stratified into three ecological zones, namely coastal, forest and savannah, and then into urban and rural EAs. The EAs were selected with probability proportional to the number of households. Households within selected EAs were subsequently listed and a systematic sample of households was selected for the survey. The survey was designed to yield a sample of 5,400 women age 15-49 and a sub-sample of males age 15-59 systematically selected from one-third of the 400 EAs.
Note: See detailed description of sample design in APPENDIX A of the survey report.
A sample of 6,161 households was selected, from which 5,919 households were contacted for interview. Interviews were successfully completed in 5,822 households, indicating a household response rate of 98 percent. About 3 percent of selected households were absent during the interviewing period, and are excluded from the calculations of the response rate.
Even though the sample was designed to yield interviews with nearly 5,400 women age 15-49 only 4,700 women were identified as eligible for the individual interview. Individual interviews were successfully completed for 4,562 eligible women, giving a response rate of 97 percent. Similarly, instead of the expected 1,700 eligible men being identified in the households only 1,354 eligible men were found and 1,302 of these were successfully interviewed, with a response rate of 96 percent.
The principal reason for non-response among eligible women and men was not finding them at home despite repeated visits to the households. However, refusal rates for both eligible women and men were low, 0.3 percent and 0.2 percent, respectively.
Note: See summarized response rates in Table 1.1 of the survey report.
Dates of collection
Mode of data collection
Survey instruments used to elicit information for the 1993 GDHS are
1) Household Schedule
2) Women's Questionnaire and
3) Men's Questionnaire.
The questionnaires were structured based on the Demographic and Health Survey Model B Questionnaire designed for countries with low levels of contraceptive use. The final version of the questionnaires evolved out of a series of meetings with personnel of relevant ministries, institutions and organizations engaged in activities relating to fertility and family planning, health and nutrition and rehabilitation of persons with disabilities.
The questionnaires were first developed in English and later translated and printed in five major local languages, namely: Akan, Dagbani, Ewe, Ga, and Hausa. In the selected households, all usual members and visitors were listed in the household schedule. Background information, such as age, sex, relationship to head of household, marital status and level of education, was collected on each listed person. Questions on economic activity, occupation, industry, employment status, number of days worked in the past week and number of hours worked per day was asked of all persons age seven years and over. Those who did not work during the reference period were asked whether or not they actively looked for work.
Information on the health and disability status of all persons was also collected in the household schedule. Migration history was elicited from all persons age 15 years and over, as well as information on the survival status and residence of natural parents of all children less than 15 years in the household.
Data on source of water supply, type of toilet facility, number of sleeping rooms available to the household, material of floor and ownership of specified durable consumer goods were also elicited.
Finally, the household schedule was the instrument used to identify eligible women and men from whom detailed information was collected during the individual interview.
The women's questionnaire was used to collect information on eligible women identified in the household schedule. Eligible women were defined as those age 15-49 years who are usual members of the household and visitors who spent the night before the interview with the household. Questions asked in the questionnaire were on the following topics:
- Background Characteristics
- Reproductive History
- Contraceptive Knowledge and Use
- Pregnancy and Breastfeeding
- Immunization and Health
- Fertility Preferences
- Maternal Mortality
- Husband's Background and Women's Work
- Knowledge of AIDS and Other Sexually Transmitted Diseases (STDs).
All female respondents with at least one live birth since January 1990 and their children born since 1st January 1990 had their height and weight taken.
The men's questionnaire was administered to men in sample households in a third of selected EAs. An eligible man was 15-59 years old who is either a usual household member or a visitor who spent the night preceding the day of interview with the household.
Topics enquired about in the men's questionnaire included the following:
- Background Characteristics
- Reproductive History
- Contraceptive Knowledge and Use
- Fertility Preferences
- Knowledge of AIDS and Other STDs.
Questionnaires from the field were sent to the secretariat at the Head Office for checking and office editing. The office editing, which was undertaken by two officers, involved correcting inconsistencies in the questionnaire responses and coding open-ended questions. The questionnaires were then forwarded to the data processing unit for data entry. Data capture and verification were undertaken by four data entry operators. Nearly 20 percent of the questionnaires were verified. This phase of the survey covered four and a half months - that is, from mid-October, 1993 to the end of February, 1994.
After the data entry, three professional staff members performed the secondary editing of questionnaires that were flagged either because entries were inconsistent or values of specific variables were out of range or missing. The secondary editing was completed on 17th March, 1994 and the tables for the preliminary report were generated on 18th March, 1994. The software package used for the data processing was the Integrated System for Survey Analysis (ISSA).
The results from sample surveys are affected by two types of errors, non-sampling error and sampling error. Non-sampling error is due to mistakes made in carrying out field activities, such as failure to locate and interview the correct household, errors in the way the questions are asked, misunderstanding on the part of either the interviewer or the respondent, data entry errors, etc. Although efforts were made during the design and implementation of the 1993 GDHS to minimize this type of error, non-sampling errors are impossible to avoid and difficult to evaluate statistically.
Sampling errors, on the other hand, can be measured statistically. The sample of eligible women selected in the 1993 GDHS is only one of many samples that could have been selected from the same population, using the same design and expected size. Each one would have yielded results that differed somewhat from the actual sample selected. The sampling error is a measure of the variability between all possible samples; although it is not known exactly, it can be estimated from the survey results.
Sampling error is usually measured in terms of standard error of a particular statistic (mean, percentage, etc.), which is the square root of the variance of the statistic. The standard error can be used to calculate confidence intervals within which, apart from non-sampling errors, the true value for the population can reasonably be assumed to fall. For example, for any given statistic calculated from a sample survey, the value of that same statistic as measured in 95 percent of all possible samples with the same design (and expected size) will fall within a range of plus or minus two times the standard error of that statistic.
If the sample of women had been selected as a simple random sample, it would have been possible to use straightforward formulas for calculating sampling errors. However, the 1993 GDHS sample design depended on stratification, stages and clusters. Consequently, it was necessary to utilize more complex formulas. The computer package CLUSTERS, developed for the World Fertility Survey program by the International Statistical Institute, was used to assist in computing the sampling errors with the proper statistical methodology.
Note: See detailed estimate of sampling error calculation in APPENDIX C of the survey report.
Other forms of data appraisal
QUALITY OF THE DATA: NONSAMPLING ERRORS
Non-sampling errors arise in surveys from a variety of causes, such as the failure to locate and interview the selected household, mistakes in the way questions are asked, misunderstanding on the part of either the interviewer or respondent, coding errors, data entry errors, etc. Although it is impossible to avoid non-sampling errors entirely, great efforts were expended in the GDHS to keep them under control. These efforts included very careful questionnaire design; a pretest of survey instruments to guarantee their functionality; a four-week interviewers' training course; careful fieldwork supervision, including field visits by headquarters' personnel; a swift editing process prior to data entry; and, finally, the use of interactive data entry software to keep keying errors to a minimum. Nevertheless, there is still a need to investigate content errors such as misreporting of ages, ignorance of dates of birth or marriage, and other recall problems.
Table B. 1 of the survey Report shows the distribution of the household population by single years of age. There is rather substantial heaping on ages ending in 0 and 5 throughout the distribution, and it is somewhat more pronounced for females than for males. Errors are particularly notable in the age reporting of females around the borders of eligibility for the individual questionnaire, i.e., ages 15 and 49. Both this table and Table B.2 show an evident deficit of women at ages 15-17 years and a corresponding surplus at ages 12-14. At the other extreme, many women of ages 45-49 have been classified as being 50-54 years old.
Little difference can be seen between the age distribution of women recorded in the household schedule and those interviewed with the individual questionnaire, indicating that response rates vary little across the age of respondents (Table B.2).
Information on the completeness of reporting in connection with a set of important variables is provided in Table B.3. The month of birth was missing for nearly 18 percent of births reported in the birth history for the most recent 15-year period; however, both month and year were missing for less than I percent of these births. For the remaining variables, the percentage of cases with missing information is low.
According to Table B.4, information on month and year of birth is available for 78 percent of all children included in the birth history; the figure for living children is 81 percent, and for dead children is only 62 percent. However, reporting is much better for recent births. For children born since 1990, complete dates are given for over 93 percent; the figure reaches 95 percent for living children, but falls to 75 percent for dead children. Table B.4 also shows that the overall sex ratio at birth is 106; from year to year there are random fluctuations around this value without any indication of bias. The sex ratio for dead children (119) is much higher than for surviving children (104), indicating higher mortality among male children.
Another aspect of Table B.4 is the heavy concentration of births in 1989 (965) relative to 1990 (605). This may represent displacement by some interviewers so as to avoid having to ask the long sequence of questions in Section 4 of the interview. The calendar-year ratio at 1990 is 72, versus 150 at 1989. The effect is to produce a spike in the distribution of births at the fourth year prior to the survey (see Figure B.I). Though the displacement is serious, there is no indication of omission of births from the birth history. For this reason, a 5-year reference period for the measurement of current fertility was adopted in Chapter 3. A 3-year rate would have been artificially low.
Note: See detailed tables (Table B.1, Table B.2, Table B.3 and Table B.4) in APPENDIX B of the survey report.
Use of the dataset must be acknowledged using a citation which would include:
- the Identification of the Primary Investigator
- the title of the survey (including acronym and year of implementation)
- the survey reference number
- the source and date of download of the data files (for datasets obtained on-line)
Disclaimer and copyrights
The user of the data acknowledges that the original collector of the data, the authorized distributor of the data, and the relevant funding agency bear no responsibility for use of the data or for interpretations or inferences based upon such uses.