INFANT AND CHILD MORTALITY IN THE THIRD WORLD MORTALITÉ INFANTILE ET JUVÉNILE DANS LE TIERS MONDE

Transcripción

1 INTER-CENTRE COOPERATIVE RESEARCH PROGRAMME Project n J: Final Report PROGRAMME DE RECHERCHE COOPERATIVE INTER-CENTRES Projet n I: Rapport final INFANT AND CHILD MORTALITY IN THE THIRD WORLD MORTALITÉ INFANTILE ET JUVÉNILE DANS LE TIERS MONDE CICRED PARIS 1983 WHO/OMS

2 INFANT AND CHILDHOOD MORTALITY IN THE THIRD WORLD Page FOREWORD by Harald HANSLUWKA, of the World Health Organization. 3 INTRODUCTION by Jean BOURGEOIS-PICHAT, Chairman of the Committee for International Cooperation in National Research in Demography 5 LIST OF THE PAPERS contributed to the project 7 FINAL REPORT by Hugo BEHM, General Coordinator 9 SELECTED CONTRIBUTIONS La mortalité infantile et de la petite enfance dans les pays africains lusophones : niveaux et tendances, by Carlos A. da Costa CARVALHO, Centro de Estudos Demográficos, Lisbon (Portugal) et Nations Unies (Rwanda) 37 Influencia del sector salud en los niveles de la mortalidad infantil cnilena, by Berta CASTILLO M., Fresia SOLIS F., Graciela MARDONES A., Escuela de Salud Publica, Facultad de Medicina, Universidad de Chile 49 Community Variations in infant and Child Mortality in Peru: A Social Epidemiológica! Study, by Barry EDMONSTON and Nancy ANDES, International Population Program, Cornell University, Ithaca, N.Y. (U.S.A) 71 Some Factors Associated with Infant Mortality in Mexico, by Irma Olaya GARCIA Y. GARMA, El Colegio de Mexico (Mexico) 91 Mortalidad infantil en Cuba ; su comportamiento en el decenio 1970-Ï979, by Raul RiVERON-CoRTEGUERA, José A. GUTIÉRREZ-MUÑE, Francisco VALDES-LAZO, Instituto de Desarrollo de la Salud, La Habana (Cuba) 129 Child Mortality in Different Contexts in Brazil: Variation in the Effects of Socio-economic Variables, by Diana Oya SAWYER and Elidimar Sergio SOARES, CEDEPLAR, Federal University of Minas Gérais (Brazil) 145 La mortalité aux jeunes âges : un essai d'approche explicative inter-disciplinaire, by Département de démographie et Unité d'épidémiologie (Université Catholique de Louvain) and Unité de nutrition et Unité de santé publique (Institut de médecine tropicale d'anvers) (Belgique) 161 SUMMARIES Differential Infant and Child Mortality in Costa Rica, (Michael R. HAINES and Roger C. AVERY) 177 Differentials in Infant and Child Mortality and Their Change over Time : Guatemala, (Michael R. HAINES, Roger C. AVERY and Michael A. STRONG) 178 Health Problems in Perinatal Period and Infancy in a Rural District of Thailand (Pensri KHANJANASTHITI and Vilai BENCHAKARN) 180 Effects offertility on Fetal, Infant and Child Mortality in Bangladesh (Ingrid SWENSON)

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4 FOREWORD Infant mortality has traditionally been viewed as an indicator of the social and economic well-being of a society. It reflects not only the magnitude of those health problems which are directly responsible for the death of infants, such as diarrhoeal and respiratory infections and malnutrition, but the net effect of a multitude of other factors, including prenatal and postnatal care of mother and infant, and the environmental conditions to which the infant is exposed. Recently, the Member States of WHO have pledged to work together "to attain the goal of a level of health for all the people of the world by the year 2000 that will permit them to lead a socially and economically productive life". A strategic consensus has been reached on how to implement this policy. In order to measure and monitor progress towards this goal, a set of 12 global indicators has been agreed upon; the inclusion of infant mortality in this list underlines the importance attached to reducing the gap in infant loss between the developed and the developing countries. It is in the developing countries where, even nowadays, one out of ten newborn will die before the first birthday. Indeed, in 52 countries infant mortality even exceeds this figure and there are still some 20 countries where every fifth or sixth newborn dies in the first year of life. Based on the current state of medical knowledge and technology, the number of "preventable" infant deaths in developing countries can be conservatively estimated to be of the order of 5 million annually. These figures speak for themselves! The new social health-oriented strategy of WHO, with its emphasis on "Primary Health Care" and the "Risk Approach", i.e. the identification of population groups with comparatively high risks of maternal and child loss, attaches great importance to statistical support for the proper planning, implementation and evaluation of maternal and child health programmes. It is for this reason that WHO welcomed the initiative of CICRED to sponsor a research project on "Infant and Child Mortality in the Third World" and was glad to co-sponsor it. The results of these studies convincingly demonstrate that despite the serious constraints resulting from inadequate and/or defective data sources, valuable insights concerning the magnitude and determinants of infant and child loss can be obtained by proper statistical data evaluation and interpretation. At the same time, it is essential to stress the fact that the results have important

5 implications for the formulation of appropriate social policies. However, the studies also show that evidence concerning the effects on mortality of modern technologies for the prevention and treatment of diseases under adverse socio-economic conditions (which prevail in many developing countries) is still, in many respects, woefully inconclusive. It is here that we are faced with a challenge for follow-up activities in order to obtain more appropriate and sensitive information and thus overcome this obstacle to efficient and effective health intervention. The CICRED research project is an important milestone and pointer in the right direction. H. HANSLUWKA Chief Statistician Global Epidemiological Surveillance and Health Situation Assessment World Health Organization

6 INTRODUCTION The CICRED Programme of Inter-Centre Cooperative Research was launched by the CICRED Fifth General Assembly, held in Mexico City in August The Programme is aimed at strengthening collaboration among population research institutions having similar scientific interests. It is based on the principles of mutual assistance and self-help. The participating institutions in each of the Programme's projects join on a voluntary basis and take charge of their share of the work and costs. The price of coordination at the inter-institutional level is kept at a minimum. The project on Infant and Childhood Mortality in the Third World was begun in the Year of the Child - when an initiating meeting was convened at the Carolina Population Center at Chapel Hill, North Carolina (U.S.A.). The concluding meeting of the project took place in Manila (Philippines) in December Given the specific interest of the project, the World Health Organization has kindly agreed to co-sponsor it with CICRED. The Project's Coordinator is Dr. Hugo Behm and, at the concluding meeting, Dr. Lado Ruzicka acted as rapporteur. The present volume provides the project's report, prepared by Dr. Behm, seven reports from national research institutions and abstracts of reports from four other institutions. The number of papers contributed to the project is actually 27, but they are at various stages of completion. Those papers which are at a very early stage, or those already published elsewhere have not been taken into account. As a matter of fact, the products yielded by the project are abundant, but highly diversified. This is not surprising, since the Third World countries themselves are deeply diversified, both from the point of view of mortality and from that of data available. Furthermore, as may be expected, the effort that the participating centres have devoted to the project is not. and in fact cannot be, evenly distributed: the human and financial resources vary according to each national institution, both in size and content: the discipline, scientific interest, specialization of the research workers assigned to the project are multi-faceted: etc. Differences in national situations and in research resources contribute to differentiating the state of achievement. Nevertheless, the results of the undertaking allow us to consider the project globally as a success. Such an achievement comes wholly from the willingness of population research institutions to cooperate with each other.

7 It is the privilege of the CICRED Chairman to express the gratitude of all the population community to the participating centres, and especially the Carolina Population Center, the host of the project's initiating meeting. The moral and financial assistance of the United Nations Fund for Population Activities and the World Health Organization has enabled CICRED to fulfil the coordination activities of the project and to publish the present volume. Jean BOURGEOIS-PICHAT March 1983

8 LIST OF THE PAPERS CONTRIBUTED TO THE PROJECT BEGHIN Y.. BARTIAUX F., BORLEEI.. BOULANGER P.M.. MASUY-STROOBANTG., NZITAD., SALA-DIAKANDA M.. TABUTIN D.. VANDERVEKEN M., LERBERGHE W., VUYLSTEKE J. : La mortalité aux jeunes âges : un essai d'approche explicative interdisciplinaire. Département de démographie. Université Catholique de Louvain + Institut de médecine tropicale. Antwerp. Belgium. BEGUM S. : Bangladesh: Levels and Differentials. Centre for Population Studies, London School of Hygiene and Tropical Medicine, UK. BLACKER J. : Experiences in the Use of Special Mortality Questions in Multi-Purpose Surveys: The Single-Round Approach. Centre for Population Studies. London School of Hygiene and Tropical Medicine, UK. BLACKER J.. BRASS W. : infant and Child Mortality in Kenya. Centre for Population Studies. London School of Hygiene and Tropical Medicine. UK. BUTANA E. : Child Mortality in British Solomon islands. Centre for Population Studies. London School of Hygiene and Tropical Medicine. UK. CAMPBELL E. Mortality in Liberia: Method, Levels and Policy Implications. Demographic Unit. University of Liberia. CASTILLO B., SOLIS F.. MARDONES A. : Chile : factores de salud asociados à la mortalidad infantil por causas evitables. Escuela de Salud Publica, Universidad de Chile. CASTILLO B.. SOLIS F., MARDONES G. : Chile.atención médica y mortalidad infantil en los 27 Servicios de Salud del pais : ano Escuela de Salud Publica. Universidad de Chile. CHAO D. : The Effects of Socioeconomic Development and Fertility Change on Infant Mortality: An Econometric Study of Taiwan, Research Triangle Institute. North Carolina. USA. da COSTA CARVALHO C.A. : La mortalité infantile et de la petite enfance dans les pays africains lusophones : niveaux et tendances. Centro de Estudos Demográficos, Lisbon, Portugal. EDMONSTON B., ANDES N. : Community Variations on Infant and Child Mortality in Peru: A Social Epidemiológica! Study. International Population Program. Cornell University, USA. GANDOTRA M.M., DAS N. : Infant Mortality and Its Causes in Gujarat State. Population Research Centre, Faculty of Science, Baroda, India. GARCIA I : Determinants of infant and Childhood Mortality in Mexico. Centro de Estudios Demográficos y de Desarrollo Urbano, El Colegio de Mexico, Mexico. HAINES M., AVERY R., STRONG M. : Differentials in Infant and Child Mortality and Their Change Over Time: Guatemala International Population Program. Cornell University, USA. HAINES M., AVERY R. : Differential infant and Child Mortality in Costa Rica: Wayne University and International Population Program, Cornell University. USA.

9 8 HILL A. : Indirect Estimates of Infant and Childhood Mortality in Kuwait. London School of Hygiene and Tropical Medicine, UK. HILL A., CALLUM C. : Childhood Mortality in Syria. Centre for Population Studies, London School of Hygiene and Tropical Medicine, UK. HILL A., MOSER K. : Childhood Mortality in Jordan. Centre for Population Studies, London School of Hygiene and Tropical Medicine, UK. KHANJANASTMTI P., BENCHAKARN V. : Health Problems in Perinatal Period and Infancy at Bang Pa In. Faculty of Medicine, Ramathibodi Hospital, Bangkok, Thailand. KIM O.K. : Childhood Mortality in Korea. Centre for Population Studies, London School of Hygiene and Tropical Medicine, UK. MARDONES G., CASTILLO B.. SOLIS F. : Chile. integridad del registro de nacidos vivos correspondientes à los 27 Servicios de Salud del pais, anos Escuela de Salud Publica, Universidad de Chile. RAHMAN Sh. : Seo-natal Mortality Patterns in Rural Bangladesh. National Institute of Population Research and Training, Bangladesh. RIVERON R., GUTIERREZ J.. VALUES F. : Mortalidad infantil en Cuba : su comportamiento en el decenio La Habana. Cuba. SAMAD S. : Infant and Child Mortality in Pakistan. Centre for Population Studies, London School of Hygiene and Tropical Medicine. UK. SOLIS F.. CASTILLO B.. MARDONES G. : Chile. mortalidad infantil por grupos de causas evitables en los 27 Servicios de Salud del pais, ano Escuela de Salud Publica. Universidad de Chile. SWENSON I : Effects of Fertility on Fetal, Infant and Child Mortality in Bangladesh. University of North Carolina, Chapel Hill, USA. SAWYER D.. SUAREZ E.S. : Child Mortality in Different Context in Brazil: Variations in the Effects of the Socio-economic Variables. Centro de Desenvolvimento e Planejamento Regional. Minas Gérais. Brazil.

10 COMMITTEE FOR INTERNATIONAL COOPERATION IN NATIONAL RESEARCH IN DEMOGRAPHY INTER-CENTRE COOPERATIVE RESEARCH PROGRAMME Final Report on the Research Project on Infant and Childhood Mortality in the Third World Hugo BEHM General Coordinator INTRODUCTION The Committee for International Cooperation in National Research in Demography (CICRED) is currently engaged in strengthening the cooperative efforts among population centers having similar research interests. In response to an earlier communication from CICRED, a number of demographic centers agreed to participate in a cooperative research on "Infant and Child Mortality in the Third World". A meeting of the representatives of 14 centers was held from September 3rd to 6th 1979 at the Carolina Population Center of the University of North Carolina, Chapel Hill, U.S.A. The objectives of the research programme were defined as follows: a) identify problems and suggest improvements in data collection, methods of estimation, analysis and international comparison of research findings in the field of infant and child mortality in the Third World;

11 10 b) study and compare on an international basis the levels, trends and main differentials on infant and child mortality in the developing countries; c) investigate the mutual relationship between fertility behaviour and child mortality; d) attempt to explain the determinants of the infant and child mortality transition in developing countries and derive the policy implications. At the meeting, it was agreed to form five working groups of the participant centres for the different subjects. A work program was defined and centres which would act as coordinators on each subject were also designated. The Concluding Meeting of the project was held at Manila, Philippines, on December 17th., The participant centres contributed with eighteen papers and W. Brass provided selected information on nine additional researches carried out at the Centre for Population Studies, London School of Hygiene and Tropical Medicine. This report summarizes and comments the most significant aspects of the contributions received as well as the discussion of the Concluding Meeting, separated in each of the initial objectives' 1 '. It also includes a brief evaluation of the project. DATA SOURCES ON MORTALITY The sources of data used by the authors show that, in developing countries, mortality registration statistics can rarely be used for mortality studies. Only in Chile, Cuba, Taiwan and the small African territories of Cape Verde and Sao Tome and Principe, registration has been considered reasonably reliable to be used; in Kuwait it is mentioned that since the late 60's, this source appears to give trustworthy results. The alternative source of data most frequently used is the population census, applying indirect methods for the estimation of mortality. This preference is explained by the growing availability of population census, improvement of new methods of estimation, and the recent inclusion of the necessary questions. This source has been used in 12 studies, particularly in population censuses carried out during the 60's and 70's. Usually estimation have been derived on the levels and trends of mortality, and on various important differentials. In the studies of Guatemala, Costa Rica and Brazil, the information provided by the population census and other sources has been used to investigate, with (1 ) The list of papers contributed is detailed on p The papers are quoted in the text under the author's name or (he country.

12 some type of multivariate analysis, the relative weight of different variables in determining the level of mortality. In recent decades, the extensive use of fertility surveys, especially in the frame of the World Fertility Survey, has opened significant possibilities of analysis on mortality in several countries, in spite of the fact that this was not its main objective (2). The group in charge of the comparative analysis of WFS could not accomplish it for various reasons. Nevertheless, the project could gather information - at times quite brief - of seven studies of this nature (Mexico, Peru, Jordan, Syria, Kenya, Pakistan and Bangladesh). Besides obtaining indirect estimations, fertility surveys permit to obtain direct measures on mortality based on pregnancy histories. It is also possible to carry out analysis at the microlevel of the family, the woman or the child. This possibility has been used, for example, in Garcia's paper with data of the National Survey on Fertility of Mexico. Finally, fertility surveys enable a more direct study of the relationship between fertility and child mortality. In spite of all its advantages, the use of fertility surveys for mortality studies is limited, among other reasons, because of the fact that mortality analysis is not its principal objective. The best alternative are surveys which have this specific purpose, where more relevant information for mortality analysis is collected. The best results are obtained by prospective studies, considering the frequency of errors of retrospective surveys. The population followed-up can not be small, because death, after all, is not a very frequent event. All this makes mortality surveys more complex and costly and consequently, of a more restrained feasibility (3). The World Health Organization has conducted child mortality surveys in recent years in Afghanistan, Algeria, Sierra Leone, Trinidad-Tobago, Mauritius and Sudan' 4 '. Information on breast-feeding, weaning, morbidity and utilization of health care services is collected in addition to socio-economic data. As reported by Hansluwka in the concluding meeting, the 11 (2) Among other papers that show the possibilities of comparative analysis on child mortality with WFS surveys, see: Arriaga E. (1980). Direct Estimates of Infant Mortality Differentials from Birth Histories. World Fertility Survey Conference. London. Caldwell J. and McDonald P. (1981). Influence of Maternal Education on Infant and Child Mortality: Levels and Causes. IUSSP General Conference. Manila. Philippines. Chackiel J. (1981). Niveles y tendencias de la mortalidad infantil en base a la Encuesta Mundial de Fecundidad. Notas de Población (CELADE). No. 27. and Chackiel J. (1982). Factores que afectan a la mortalidad en la niñez. Notas de Población. No. 28. Taucher E. (1982). Effects of Declining Fertility on Infant Mortality Levels: a Study Based on Data from Five Latin American Countries. Report to the Ford Foundation and the Rockefeller Foundation. CELADE. (3) The methods of data collection for mortality studies, with special reference to developing countries, were discussed in one session of IUSSP Seminar on Methodology of Data Collection and Analysis in Mortality Studies. Dakar. Senegal (4) Reports are being published by WHO and the respective governments. Summary articles on findings from Afghanistan and Algeria were published in World Health Statistics Quarterly. Vol. 34. No. I

13 12 experience with the country-studies is intended to be evaluated by the end of 1982, before launching new such surveys in the future. For various reasons it was not possible to have the results of the various surveys on mortality carried on in some French-speaking African countries. Among the studies of this type, there was available the paper of Khanjanasthiti and Banchakarn, which consists in a follow-up of 1119 new-born in a district close to the capital of Thailand. Swenson analyzes fetal and infant death in a group of pregnancies in 132 villages of a district near the capital of Bangladesh, to determine mainly what effect has pregnancy spacing on this mortality. In an investigation of more limited reach, Rehman studies neonatal mortality in a district of Bangladesh, controlling within 28 days a total of 838 born alive children whose birth had not technical attendance. These experiences show the advantage of the more complete information thus obtained, but likewise show the problem of the representativeness of local samples and the different bias to which they are exposed. The analyzed experience shows that at present and in a near future, mortality studies in developing countries, especially in several countries of Africa and Asia, should use information sources other than death registers, due to their deficiency. If they are acceptably reliable, their analytical possibilities should be fully exploited; this does not always occur. In some countries, these registers are deficient at a national level but acceptable in some regions, frequently in the most important urban areas. Even with these restrictions, mortality studies of these populations can be very useful (5). Without dismissing the possibility of encouraging the development of special mortality studies, the collected experience also indicates that sources of data of more immediate use in many developing countries, mainly in Africa and Asia, are fertility or demographic surveys and population census. As to the former, the possibility of including a mortality section should be promoted. Regarding population census it has generalized the inclusion of questions permitting indirect estimations of child mortality. It is a matter of taking full advantage of these analytical possibilities. The papers of Avery and Sawyer illustrate these perspectives not only referred to estimations of levels, trends and differentials, but also to the analysis of different determinants of mortality. We will refer further on to the importance of elaborating a theoretical framework for analysis. It is convenient to mention other sources of information for the study of mortality. Where health services exist, meaningful information is collected with better data on the causes of death. The extension of primary (5) In Brazil, for instance, vital statistics are in general only referred to the State capitals. Nevertheless, the Special Group of Demographic Analysis of the SEADE Foundation, has carried out studies of high interest using the death registers of the State of Sao Paulo. See: Segundo Encontró Nacional. Associaçao Brasileira de Estudos Poblacionais. Aguas de San Pedro de Octubro de 1980.

14 health care in many developing countries, mainly in its rural areas, - if the program is well accomplished - is generating data on population and the occurrence of pregnancies, births and deaths. These sources of information are not often used in mortality studies. Such use has the advantage of linking health professionals who are direct operators of interventions aiming to reduce mortality, to demographers and other professional groups interested in the same subject. The papers presented to the project also show that the problem of sources of data for mortality studies, less than a controversy on advantages and disadvantages of different options, should consist in the intelligent use of all the available sources of data on the population under study. The advantages of an interdisciplinary collaboration is obvious. 13 THE METHODS OF MORTALITY ESTIMATION Mortality index can be directly calculated when civil registrar data is available, in surveys with pregnancy history and in follow-up studies of a given population. The need to derive mortality estimation from population surveys or census has promoted the development of a great number of indirect methods. Blacker has made a brief revision of these methods. In regard to mortality during the first years of life, the most usual methods are based on the proportion of dead children out of total children ever born of women classified by age. Sullivan and Trussell have modified the original method elaborated by Brass in Further refinements have also been developed by Preston and Palloni, using the age distribution of surviving children, which has the advantage of eliminating assumptions on fertility patterns. Indirect estimations are exposed to various sources of error, one of them being the nonfulfilment of the assumptions implied in the method. Nevertheless, they seem in general to be quite robust on this respect. On the other hand, methods have been developed so as to correct some of them (6). It is not important either what is the variant of method used, because they usually lead to similar estimations. The main problem consists in errors in the declaration of children ever born and of dead children. When estimations have been evaluated by comparison with reliable sources, sometimes important differences have been found; for example, in geographic contrasts of mortality (7). But in general, experience shows that estimations of infant and child mortality are (6) A description of the several indirect methods of child estimation mortality in: Hill K.H.. Zlotnick H. and Trussell J.J. (1981). Demographic Estimation: a Manual of Indirect Techniques. National Academy of Sciences. USA (forthcoming). (7) Tabutin D. (1979). Mortalité des enfants dans les pays en développement: observations et analyses. Chaire Quetelet Louvain-la-Neuve.

15 14 internally and externally consistent (8). The use of indirect methods in the study of this mortality has shown that they can contribute with important findings on early mortality levels and differentials in countries where no better information is available (9 >. Naturally, estimations should always be judged with precaution. The papers contributed by the centres do not have the purpose of a systematic evaluation of the estimating methods, obviously because several of them were made in regions where these methods were applied because of lack of better information. When indirect estimates have been compared with a reliable figure, there has been an acceptable agreement. There are two aspects that should be pointed out. The method originally developed by Feeney and elaborated afterwards by Trussell (10) permits to derive estimations of mortality which refer to dates prior to the survey or census, that is, the estimation of mortality trends. This is a significant progress because, in this way, it is possible to analyze the transition of infant and child mortality in these countries at a national level as well as in significant groups of population. Several papers study the consistency of national estimations thus obtained by comparing estimates derived from two surveys or ceasuses. Results obtained in studies of Jordan, Kuwait, Syria and Kenya are in general quite satisfactory. It is also evident, in this experience, as noted by Blacker, that estimations derived from data of women and years old lead to an overestimation of mortality which alters real trends and should be rejected. The reason is probably that children born by mothers of those ages consist largely of first order births which are generally subject to a higher mortality than those of higher order. In the first age group, the greater death risk of early pregnancies is added. It has also been observed that the use of the North model life tables leads to underestimations of mortality. An interesting application is made by Begum in Bangladesh where past trends of infant mortality are estimated for subgroups defined by the place of residence, education, the religious group and other significant characteristics. It is not possible to judge on the reliability of the contrasts observed in levels and trends, except to say that they are coherent with what was expected to be obtained. If this type of trend estimations proves to be reliable in further experiences, indirect methods would be providing (8) Hill K. (1981). An Evaluation of Indirect Methods for Estimating Mortality. IUSSP Seminar on Methodology of Data Collection and Analysis for Mortality Studies. Dakar. Senegal. (9) Behm H. (1978). Mortalidad en los primeros años de la vida en la América Latina. Notas de Población (CELADE). No. 16. (10) Feeney G. (1980). Estimating Infant Mortality Trends from Child Survivorship Data. Population Studies. Vol. 34. No. 1. and Hill K. et. al. Demographic Estimation... op. cit.

16 a very rich information for the analysis of the factors that affect the course of mortality in these countries. The study of Haines et. al. in Guatemala is a good example of the exploitation of census data in order to estimate differentials and their trends, as well as to provide information for a multivariate analysis. They used the surviving children method, using the age distribution of the surviving children of the women, obtained by an "own children" style allocation of children to a mother within the household. The census data was evaluated and it was possible to correct some errors in the declaration of children ever had. It was also necessary to estimate the number of surviving children, information that did not exist in one of the two used population censuses. It was found that the estimates using the surviving children method were higher than those using the Sullivan age model. A clear explanation of these differences could not be found but it is important that "the mortality differentials were usually in the same direction, although the magnitude changed." 15 MORTALITY LEVELS AND TRENDS Table 1 summarizes estimations of national levels of infant mortality and its trends according to the papers presented by the Centers. Certainly, they do not exactly represent the prevailing situation in all developing countries; besides, estimations have a variable degree of reliability. In spite of this, they do emphasize some interesting characteristics. It is evident that infant mortality is extremely variable in the Third World, much more than in developed countries, a situation determined by the many different social, economic and cultural conditions which prevail in those countries. In the 70's, the rate of mortality is relatively low in the three countries of Latin America: Cuba, Costa Rica and Chile 0". It is estimated that Kuwait, Syria, Korea, Mexico, Sao Tome and Principe have reached an average level of mortality (40-70 per 1000). The rates approximate 100 per thousand in Kenya, Peru and Brazil, while in Mozambique, Liberia, Bangladesh and Pakistan there is a considerable delay in the reduction of infant mortality, reaching rates higher than 120 per thousand. With all the restrictions derived from the used methods of estimation, this table also presents the trends of mortality in the first year of life in recent decades. They reveal an important fact: in spite of the very dissimilar historic conditions presented in these countries and expressed in very different levels of mortality, there is a general tendency to a decline (11) Infant mortality rates per 1000 in 1980 are: 19.6 in Cuba en Costa Rica and 33.0 in Chile.

17 16 TABLE 1. - Estimates of infant mortality rates, selected developing countries, Countries Infant mortality rates (per 1000) AFRICA Cap Vert Kenya (b) Liberia Mozambique Sao Tome and Principe ASIA Bangladesh Korea (a) Kuwait (d) Pakistan Syria LATIN AMERICA Brazil (a) Chile Costa Rica Cuba Guatemala (a) Mexico Peru OCEANIA British Salomon Islands (e) (e) (c) (a) Mortality index is 2% per (b) Average of Feeney's estimates. (c) For females, (d) Mean of kuwaities and non-kuwaitis. (e) Official rates, considered under-estimations. in rates. Nevertheless, the intensity and chronology of this decline are quite variable. With the exception of Cuba, Costa Rica and Chile, existing rates in the 50's were very high and many of them exceeded up to 140 per thousand. The decline was early and steady with a reduction that can reach up to half of the initial rate, in Kenya and the small territories of Cape Verde and the British Solomon Islands. Of greater significance is what we observe in Pakistan, Mozambique and Brazil, which are countries with a much larger population. The decline of mortality in these countries is more belated and of less intensity, in such a way that rates for the 70's still exceed per thousand. In Bangladesh, there is not even a clear trend towards a decline and it could even have a recession towards On the contrary, in Latin America, Costa Rica, Cuba and

18 Chüe - this latter in a smaller measure - were, in the 5O's, in a more advanced phase of mortality transition with a level similar to the one reached in recent years by the already mentioned African and Asiatic countries. These countries in which mortality transition occurs earlier, are also characterized by a continuing marked decline, which maintains itself until the most recent date. The analysis of the historic transition of mortality occuring in the past, in today's advanced countries, shows that infant mortality was the last to join the process of decline. In several countries of Europe, prevailing rates at the end of the XIX century bordered 200 per thousand and sometimes a clear decline did not take place until the early XX century. Nevertheless, there are two fundamental differences between this historical experience and what is happening today in developing countries. The first is favorable to the latter ones and refers to the current existence of impressive technological advances in the prevention of disease and death. Of course, these means did not exist at the time when the developed countries initiated the decline of early mortality. On the contrary, they then benefited for being centres of colonial empires whose dominions contributed to their own progress. On the opposite, today's Third World is characterized by its dependency on central economies. Some of the studies of mortality determinants, presented by the Centres, help us to examine how this contradiction is being solved. As mentioned in the initial document prepared by the Coordinator of the project (12), the diversity of current situations in regard to mortality, as shown by the mentioned estimates, express the very different historic conditions of the studied populations. Thus, its comparative study should be an important source for its better interpretation. This project achieved this purpose only in a limited way but in any case, it has been the source of important suggestions for further investigation, as will be seen further on. 17 MORTALITY DIFFERENTIALS The papers presented explore differentials of infant and child mortality in terms of available variables in censuses and surveys. The finding of these differentials does not explain "per se" the mechanisms determining mortality. Nevertheless, these differentials describe significant contrasts of mortality and are the basis to elaborate hypothesis on its genesis. We will consider the most significant differentials, mainly associated to geographic variables and to maternal education. Its (12) Behm H. (1979). Infant and Child Mortality in the Third World: Background Information and Proposals for Cooperative Studies Among Demographic Centers. CICRED.

19 18 significance will be discussed further in relationship to multivariate analysis. Geographic contrasts within countries should be interpreted with caution because basic data has a variable reliability in the different regions. Furthermore, indirect estimations are subjected to bias linked to internal migration. Table 2 summarizes geographic differentials. Certainly these differentials are properly socio-geographic ones, because - with the exception of special cases, as death by malaria-they mainly express differences in social and economic mortality determinants of each region. The table seems to show that when mortality is extremely high, geographic differentials are of less importance and that high mortality is as much a characteristic of urban as well as rural region. This is the situation of Bangladesh in 1960, Pakistan in , Guatemala in 1959 and Mexico when birth cohorts are included since the year Generally, the excess of mortality in rural populations is not higher than 10%. When mortality declines, the geographic differential increases because the decline is higher in urban zones. In this way, rural rates can duplicate urban mortality. It is also noticeable that regions which include larger cities, especially the national capital, have relatively low mortality. This evolution is quite clear, for example, in Guatemala where estimations of ^ are compared for 1959 and The excess of rural mortality over the urban one has increased from 6 % to 48 %, due to the fact that during this period, rural mortality has not a significant decline while in the urban sector it reaches 32%. In the population of the capital city of Guatemala, the decline reaches 48 %. In two countries of relatively low mortality, Chile and Cuba, geographic contrasts are considerably more intense in the first mentioned country. In Brazil, the greatest difference is not found in the urban/rural contrasts; on the other hand, the backward Northeast duplicates the mortality of the Southern Region, which has the greatest industrial centre of Latin America. The pattern of change of urban/rural mortality observed in these countries is not the same as the one registered in the past in to-day advanced countries. Towards the end of the XIX century, for example, the rate of urban infant mortality exceeded the rural one in approximately 50 % in Norway and Sweden; a more intense decline in the cities made this differential disappear in the first third of the XX century. Nevertheless, in Bulgary we can find the pattern of the earlier and most sustained urban decline since the 1930's (l 3). The factors that likely determine geographic differentials are discussed further on. It is convenient to emphasize that rural mortality is higher and that it makes less progress in countries of the Third World. In (13) United Nations (1978). Determinants and Consequences of Mortality Trends. ST/SOA/SER.A/50.

20 19 TABLE 2. - Geographical differentials of infant and child mortality, selected developing countries, Country Year Mortality index (a) Higher mortality populations Lower mortality populations Ratio higher/ lower AFRICA Angola Mozambique ASIA Bangladesh Jordan Pakistan LATIN AMERICA Brazil (b) Chile Cuba Guatemala Peru Mexico Cohort Cohort lio 2«Jo IMR IMR lio Death per 1000CEB fem IMR IMR 2<Jo Inf + child Mortality ratio to nation, mort. iio Luanda (capital) Centre Rural Rural Town and large villages Medium small villages 95 Rural 145 Northeast Urban Northeast rural Southern provinces Eastern provinces Rural Rural Andean region Rural + Rural Rural IOCK t*7 /\J 31% Malanga Bié Benguela South North Urban Urban Aman (capital) Zarka-Irbia Urban South urban South rural 229) ) 126) 137) 134) 116) Provinces with largest cities 21 Central provinces Urban Urban Lima (cap.)- Urban Urban Urban % 9% NE/S = (a) Per 1000 births. (b) Effects of other intervenient variables controlled. IMR: Infant mortality rate. CEB: Children ever born.