Estimating maternal mortality in Djibouti: an application of the sisterhood method

Abstract

In many developing countries even crude estimates of the level of maternal mortality are lacking and the prospects of fulfilling this need using conventional sources of vital registration and health service statistics are not encouraging. The constraint this imposes on the effective planning, management and evaluation of the programmes now being launched to reduce these neglected deaths is self-evident. It is less obvious how the majority of developing countries can be expected to meet the call for reliable estimates of maternal mortality by 1995. The sisterhood method provides a means of obtaining population-based estimates using household surveys for data collection. This paper describes the application of the method in Djibouti in the context of a rapid multi-purpose household survey in difficult field circumstances. In recent years the reduction of the level of maternal mortality in developing countries has become a priority for both national governments and international agencies. Attention has been drawn to the wide range of levels within and between countries and to the huge discrepancies in the lifetime risk of maternal death for women in the developed compared with the developing world. This risk has been estimated to range from 1 in 19 in West Africa to almost 1 in 10,000 in Northern Europe.

PIP: The sisterhood method, developed in 1987, of estimating maternal mortality is applied to Djibouti population data. The method is based on the reports of the proportion of adult sisters dying during pregnancy, childbirth, or the puerperium. The method is used where date collection is limited or the field circumstances are difficult. The advantage is that it can be used with small sample sizes to produce stable estimates. It is useful in gauging the extent to which there has been underreporting of maternal deaths. 4 questions and the 5 year age group of the respondent are required. Precise working is a requirement. The survey was implemented in February, 1989 using a modified version of the EPI/CDD cluster sampling method. Comprising the national sample, 30 clusters were involved in Djibouti City and 30 clusters in 4 rural areas using probability proportional to size (PPS) methods and the 1983 population census sampling frame with a 3% increase. Within 100 ever married women were selected per cluster and 4000 respondents were desired. The assumption was about 500 per 100,000 live births, a total fertility rate of about 6, and an error rate of 6%. The questionnaire was translated from French into Afar, Arabic, and Somali. The method of training interviewers, the group management, and pretesting are described. The 4 questions in English were 1) How many sisters have you ever had who were born to your mother?. 2) How many of these sisters reached age 15, including those now alive now? 3) How many of these sisters reaching age 15 are dead? and 4) How many of these dead sisters died while pregnant, or during childbirth or in the 6 weeks after delivery, an abortion, or a miscarriage? The results of the 7408 females 15-49 years interviewed were that the lifetime risk of dying of maternal causes were found to be 0.049 or 1 in 20. Using a total fertility rate of 6.8, the maternal mortality ratio was calculated as 740 maternal deaths per 100,000 live births 11.6 years prior to the survey. The results of the assessment of the quality of the data showed underreporting of the 2 youngest age groups, which suggests misreporting. Severe age heaping on ages of respondents ending in 0 and 5 was also apparent. In spite of the difficulties, the results are plausible and lend support to the method.