a Policy Research Division, The Population Council, One Dag Hammarskjold Plaza, New York, NY 10017, USA. E-mail: gkiros{at}popcouncil.org
b Population Studies and Training Center, Brown University, Box 1916, Providence, RI 02912, USA. E-mail: Dennis_Hogan{at}brown.edu
Abstract
Background Civilian-targeted warfare and famine constitute two of the greatest public health challenges of our time. Both have devastated many countries in Africa. Social services, and in particular, health services, have been destroyed. Dictatorial and military governments have used the withholding of food as a political weapon to exacerbate human suffering. Under such circumstances, war and famine are expected to have catastrophic impacts on child survival. This study examines the role of parental education in reducing excess child mortality in Africa by considering Tigrai-Ethiopia, which was severely affected by famine and civil war during 19731991.
Methods This study uses data from the 1994 Housing and Population Census of Ethiopia and on communities' vulnerability to food crises. Child mortality levels and trends by various subgroups are estimated using indirect methods of mortality estimation techniques. A Poisson regression model is used to examine the relationship between number of children dead and parental education.
Results Although child mortality is excessively high (about 200 deaths per 1000 births), our results show enormous variations in child mortality by parental education. Child mortality is highest among children born to illiterate mothers and illiterate fathers. Our results also show that the role of parental education in reducing child mortality is great during famine periods. In the communities devastated by war, however, its impact was significant only when the father has above primary education.
Conclusions Our findings suggest that both mother's and father's education are significantly and negatively associated with child mortality, although this effect diminishes over time if the crisis is severe and prolonged. The policy implications of our study include, obviously, reducing armed conflict, addressing food security in a timely manner, and expansion of educational opportunities.
KEY MESSAGES
Keywords Child mortality, parental education, war, famine, disasters, Africa, Ethiopia
Accepted 22 June 2000
Armed conflicts in many countries in Africa have increasingly targeted civilian populations, resulting in high casualty rates, widespread human rights abuses, forced migration, and in some countries, the total collapse of governance. Armed conflict has a significant impact on the health of young children through the destruction of health service infrastructure and resource allocation decisions detrimental to children.1 African famines have been associated with excess mortality resulting from starvation and epidemic diseases.2,3 Famines and war have devastated countries in sub-Saharan Africa such as Angola, Chad, Eritrea, Ethiopia, Mozambique, Rwanda, Sierra Leone, Somalia, and the Sudan. Although the causal relationship between wars and famines is complex,4 famines have often been associated with wars. Children under 5 years of age have been the population most affected by famine and war.514
War often adversely influences the ability of famine-prone countries to escape mass starvation.4 It typically destroys food production and distribution, dislocates mass populations, and forces the relocation of refugees. War also undermines social services, in particular health services, as meagre government resources are taken away from social services to finance military build-ups. Deliberate diversion of food supplies by various armed factions as well as the disruption of transport and marketing and economic hardship often cause severe food shortages. The impact of these factors on the nutritional status of the population in sub-Saharan Africa is severe. Reaching the affected population with medical assistance has proven much more difficult for aid agencies. Civilian-targeted warfare and political violence constitute one of the great public health challenges of our time. Parental roles in reducing excess child mortality in Africa will be examined here by considering Tigrai-Ethiopia, which was devastated by civil war and famine from 1973 through 1991.
The Ethiopian Case
Ethiopia is the second largest country in sub-Saharan Africa with 60 million people. In the 1970s and 1980s Ethiopia was ravaged by war and experienced more devastating famines than any other country in the world.13,1519 As in most nations undergoing chaos and crisis, some regions were much more heavily impacted than others. Eritrea (which became an independent state in 1993) and Tigrai, a region in northern Ethiopia, were the most heavily affected regions, and bear the legacy of decades of war, economic devastation, and war-aggravated famine.
The Study Area
Ethiopia is divided into nine autonomous Administrative Regions known as kilil. Tigrai, situated in the northern part of Ethiopia, is an autonomous region with an estimated total area of about 80 000 km2 and a population in 1998 of 3.6 million.20 The region is divided into four administrative zones and 35 weredas (they represent districts with average population size of 100 000). The people of Tigrai are identified by their use of the Tigringa language, which evolved from the ancient language, Geez.
The topography of Tigrai is characterized by its plateaus with mountains in the centre varying in altitude from 2000 to 3000 m above sea level. About 85% of the total population of the region are engaged in the agricultural sector and lives in rural areas. All economic activities in Tigrai are at subsistence level and hence are easily disrupted by seasonal variations and shortage of rainfall. Droughts, famines and destructive wars have characterized the history of Tigrai,15 with at least 18 recorded instances of famine in the region since 1800.21
The educational level in Tigrai is very low. Only 20% of the people aged 10 years and older can read and write. The overall level of literacy varies by sex: the proportion of literate males, 28%, is double that of literate females, at 14%. The literacy rate is 57% in urban areas which contrasts sharply with the rural literacy rate of 14%. Addressing health issues is problematic. Health institutions in Tigrai are scarce and inadequately equipped. The water situation is characterized by extreme scarcity, poor sanitation, and inaccessibility (along with a very rugged terrain). Only 23% of the population receive clean water while the remaining segment is forced to use unprotected and contaminated water; in most places animals and humans use the same water source. Availability of sanitary facilities is almost negligible.
During the civil war, the dictatorial government's counter-insurgency strategy targeted the civilian population and was the central cause of the chronic humanitarian crisis of the 1980s.13,1618 The dictatorial regime used food aid and famine as political weapons for the subjugation of many communities, in particular the Tigraians. Because of military selectivity, this destructive campaign targeted and impacted some Tigraian communities more than others. For example, the Mengistu government used the restriction of food delivery during the 19841985 famine to further marginalize the Tigraian peasantry; its strategy was one of starving the opposition into submission.22 Starvation, the dislocation of a large section of the population to harsh areas, and reduced agricultural productivity have aggravated famine conditions and facilitated the sufferings of the population. These activities were consonant with the war strategy of draining the sea to catch the fish.18
The Role of Parental Education in Reducing Excess Child Mortality
The main purpose of this study is to examine the role of mother's and father's education in reducing excess child mortality in a region in Africa troubled by war, famine, and recurring droughts. Parental education, through its impact on household income, has both direct and indirect effects on child survival. The effect is more pronounced in environments dominated by uncertainties that are created by both men and nature. For example, household income can have a dramatic effect in reducing malnutrition, especially during periods of crisis where food prices usually rise dramatically. Education also plays a direct role in shaping parental behaviour towards their children.23 The inverse relationship between mother's education and infant and child mortality is supported by many studies in widely different populations.2327 Caldwell24 suggested that educated mothers are more likely to shift from a fatalistic acceptance of health outcomes towards the implementation of simple health-promoting practices. This often includes an increased capacity to manipulate modern medical systems.
Hobcraft27 provides a detailed review of recent evidence on the effects of maternal education on child mortality. One possible pathway by which maternal education enhances child survival is higher standards of cleanliness among educated mothers. Another pathway, which receives considerable attention, is the role of education in ensuring that mothers utilize health services for their children. Maternal education may also be regarded as an indicator of the mother's skill level and the degree to which she can effectively employ the resources at her disposal to increase her children's survival chances.28 In addition, maternal education may be associated with greater emphasis on child quality and the empowerment of women. In a subsistence economy, however, maternal education can be a disadvantage because it is usually associated with shorter duration of breastfeeding.29
Empirical evidence shows that infant and child mortality in sub-Saharan Africa decreases with greater paternal education.23,30 Caldwell30 suggests that father's education increases the survival chances of children through the greater knowledge and affluence it brings to the household. In this study, we hypothesize that the impact of parental education on child mortality will be more profound during times of crises because educated parents are more likely to be able to protect their children from military conflict, famine, and disruptions of the social and physical environment. Educated parents are more likely to have food reserves for their children during famine periods and fathers with higher education are expected to have better coping strategies and better economic resources. Consequently, they are more able to send their children to safe places during war. Because of these independent avenues of influence of mother's and father's education we hypothesize that mother and father's education will have a joint impact on child survival during time of crisis.
Data and Methods
The principal source of data for this study comes from the 1994 Housing and Population Census. The 1994 Housing and Population Census of Ethiopia is the second of its kind in Ethiopia and the first one to cover the entire Tigrai region. The data used for this study are based on a 20% sample of all households in Tigrai yielding a total of 144 090 households, 142 614 women in the age group 1549, 414 445 children, and 87 025 child deaths.
Data quality
In an earlier study we used various measures of data quality to prove that the data gathered in the Tigrai region is good.31 In fact, using a method known as own-children, we successfully matched 94% of all children under 5 years to their mothers. Most of the unmatched children were either children that belonged only to the head of the household (who is male and has another wife) or orphans. Also, other researchers who evaluated the quality of the entire 1994 Ethiopian Census found that the data for Tigrai had fewer errors than any other region, with the exception of the capital city, Addis Ababa.31 In addition, the Post-Enumeration Survey confirmed the quality of the census data. The better-than-expected data quality can be partly attributed to the co-operation and commitment of officials in the Tigrai region. Regional officials were enthusiastic about obtaining, for the first time, information on Tigrai's popu-lation and housing for the use of its policy makers and administrators.
Since our focus in this study is on levels and differentials in child mortality by parental education, the quality of information on the number of children who were born, survived, or died is of particular concern. One way of evaluating the quality of data for reported number of children ever born and number of children dead is by computing average parity and average number of children dead by age group of women. Unless there is dramatic change in the fertility and mortality schedules, it is expected that parity and child deaths will increase with the age of women. Table 1 presents the number of women and the number, mean, and standard deviation of children ever born and those who died by age group of women. As expected both average parity and average number of child deaths increases with age of women, suggesting data of acceptable quality.
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In addition to the census information, we obtained time series data from 1978 to 1988 on food security in each wereda from the World Food Program (available at URL: http://www.wfp.it/vam/ethiopia) with linkage to the corresponding wereda. The data are collected by the Disaster Prevention and Preparedness Commission (DPPC) of Ethiopia in collaboration with the UN Emergency Unit for Ethiopia, and the UN World Food Program. Data for the period 19891991 are not available because the whole region was under the control of the TPLF (Tigrai People's Liberation Front), an opposition force waging war against the dictatorial military regime for 17 years. However, government and UN agency reports about the experience of the weredas respective food shortages gives sufficient information to identify the vulnerability of the weredas to food crisis. Further, the weredas are divided as low or high war intensity areas based on our experience in the region and local government publications. It should be noted, however, that the weredas were grouped in terms of their food crisis and war intensity independent of the knowledge of infant mortality data. This is because no estimates of infant and child mortality were available for the entire region and the 1994 Census was the only one to cover the region.
Child mortality estimates were obtained using the Trussell variant of the Brass child survival method32 to estimate child mortality from information on child survival collected in censuses and surveys,33 based on the Coale-Demeny west model of the life table.34 This child mortality measure is the most robustly estimated index that can be constructed from the census data3537 and has been widely used in the investigation of child mortality in developing countries.26,35,39,40
Statistical tests for comparing the estimates of probability of dying by age 5 by parental education across various strata were performed using the Z-test for comparing two proportions.41 The Z-statistic to test the difference between two proportions is given by
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The programpretesti, an ado-file in STATA 6.0 was used for this purpose.
Multivariate models were fitted using Poisson regression to examine the associations between child mortality and parental education. The mulitivariate analysis was built using number of children dead as a dependent variable, which is discrete and assumes limited values. The Poisson regression model,4244 using number of children ever born, reflecting the degree to which deaths could occur, is useful and more appropriate when the outcome is a count, as in our case. It models the number of children dead (Di = 0,1,2, ..., n) per woman as a function of parental education, age of woman, urban-rural residence, and wereda's vulnerability to food crisis and war intensity.
Let Di = the number of children who have died per woman i, which follows a Poisson distribution, and di = the expected number of deaths per woman i. The Poisson regression model can be stated as:
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where Ci is the number of children ever born to woman i used as exposure variable, ß0 is the intercept, the ßis are regression coefficients, and the xis are the explanatory variables including a combination of mother's and father's education. Age of woman, type of residence (urban/rural), and district's vulnerability to food crisis and intensity of war are used as control variables.
Results
Figure 1 presents the probability of dying by age 5 per 1000 births for the period 19791994 by both mother's and father's education. It clearly reveals enormous variation in child mortality rates by parental education. Child mortality is highest among children born to illiterate parents and decreases with both mother's and father's education. It is interesting to note that the gap in child mortality by parental education becomes wider during periods of great disruption (such as the immense military offensives in the beginning of the 1980s and the Great Ethiopian Famine of 19841985) and diminishes after the end of the civil war in 1991. Statistical tests of child mortality differentials at consecutive periods suggest that the effect of mother's education was statistically significant (P < 0.05) until the end of the war, but became non-significant then after. Regarding the effect of father's education, the differences in mortality of children born to fathers with primary education and illiterate fathers were statistically insignificant except in the early 1980s, where child mortality was significantly lower among children born to fathers with primary education than among those born to illiterate fathers. On the other hand, throughout the period, children born to fathers with above primary education had significantly less mortality than those born either to illiterate fathers or fathers with primary education (P < 0.05).
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The average child mortality rates by mother's and father's education throughout the period 19791994 is summarized in Table 2. Again, the great survival advantage of being the offspring of parents with schooling is confirmed. Child mortality is estimated at 200 and 156 deaths per 1000 births for illiterate and literate mothers (a difference of 22%), respectively. This difference is statistically significant (P < 0.05). Again, estimates of child mortality by father's education are significant, and children born to illiterate fathers having the highest mortality rate (201 per 1000). However, the estimates decline to 178 and 114 when the father has primary, and above primary, education respectively. While overall father's education is found to be significant in lowering child mortality, the difference between being illiterate and having primary education is not statistically significant.
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Child mortality estimates by parental education and community food security status is presented in Table 4. As one would expect, child mortality is found to be higher in the drought prone areas (Table 4
). Further, child mortality estimates by parental education are consistently lower in areas less affected by food crisis compared to areas more affected by food crisis. Substantial variation in child mortality is found by parental education in both the less vulnerable and more vulnerable weredas. The impact of mother's education in reducing child mortality is significant in both types of areas. Overall, the role of father's education is significant in both less and more vulnerable communities. In addition, statistical tests of differences in parental literacy and child mortality in areas vulnerable to food crisis reveal that the difference is only significant when the father has acquired above primary education. That is, the effect of mother's education in reducing child mortality is about the same regardless of the area's food crisis.
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All three regression models suggested a significant reduction in number of children dead by all combinations of parental education compared to when both parents are illiterate. Again, taking into account age of mother (Model 2), all the regression coefficients still remain strong suggesting a significant reduction in number of child deaths by parental education. The coefficients also confirm, obviously, that the number of deaths increases by age of mother, and this association is significant. In addition to Model 2, Model 3 takes into account urban-rural, food crisis, and war intensity. Even after controlling for the additional covariates, the effect of parental education in reducing number of child deaths remained consistent and strongly significant.
As explained earlier, the urban areas of Tigrai were severely hit by both land battles and air strikes. The observed positive and significant coefficient of urban residents compared to rural areas reveals that children of urban residents suffered excess deaths compared to children in rural areas. This can be explained because of the devastating crisis in urban areas. Health services were almost non-existent, shortage of clean water was severe, and electricity was not available. Model 3 also shows that the number of child deaths per woman in areas more prone to food crisis is significantly higher than those in less prone areas. Likewise, number of deaths is significantly higher in communities with high war concentration.
In Table 5, the statistical significance of the coefficients of each combination of mother's and father's education was compared with the reference category (both parents illiterate), and all coefficients were found to be significant. We also examined the statistical difference of each parental education coefficient. Table 6
summarizes the significant differences between the various categories of parental education using the results of the final model (Model 3) shown in Table 5
. Chi-square values for testing the quality of two coefficients (estimates) are presented in Table 6
. All differences are statistically different from zero, but with two exceptions. First, the difference is insignificant when the mother is literate and father is illiterate (1) and mother is illiterate and father has primary education (2). The difference is also insignificant when the mother is illiterate and the father has above a primary education (3) and when the mother is literate and the father has a primary education (4).
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Severe famines and prolonged war in Africa have generated violence, hunger, the uprooting and mass migration of families and communities, the destruction of the already meagre health services and the collapse of governance. These have affected the lives of millions of civilians in many countries of Africa. The number of refugees and internally displaced populations resulting from famine, war, civil strife, and persecution in Africa is increasing. Severe public health consequences have been documented following such emergencies related to famine and armed conflict in Africa8 and most deaths in these populations have occurred among children under 5 years of age. Since the 1970s, Tigrai has been wracked by wars, famines, and recurring droughtsmore so than any other region in Ethiopia. The combination of these natural and man-made catastrophes has had far reaching consequences for the lives of the people. Hundreds of thousands of people were uprooted from their villages and became refugees in the neighbouring Sudan while others were internally displaced. In addition, social services, including health services, were devastated. Consequently, child mortality in Tigrai is excessively high. The focus of the study has been on the role of parental education in diminishing this mortality rate.
The study provides evidence on important points. Notwithstanding the limited educational opportunity in the region, the role of education in depressing child mortality is evident. A marked difference in child mortality rates was found by parental education. Both mother's and father's education are found to have independent significant impacts in reducing child mortality. Regardless of parental education, as one would expect, children born in communities that are prone to food shortages and most affected by the civil war had higher mortality. In the communities less affected by war, the effect of mother's and father's education is strong and significant. On the other hand, no significant impact of parental education is observed in areas devastated by war except when the father has above primary education. This suggests that fathers with above primary education have more resources and know better survival strategies during wartime than those with less education.
Mortality varied substantially in both drought prone and less drought prone areas by both mother's education and father's education. Another important finding of the study is that child mortality was significantly higher in urban areas compared to rural areas. In this study, both mother's and father's education are strongly associated with child survival, although this effect diminishes over time if the crisis is severe and prolonged. The policy implications of our study include, obviously, reducing armed conflict, addressing food security in a timely manner, and expanding educational opportunities.
Acknowledgments
Support for this analysis was provided by the Compton Foundation, which has awarded Brown University a grant for policy-relevant research training on Ethiopia, Belfer Family Graduate Fellowship in Public Policy, and the Robert E Turner Distinguished Professorship in Population Studies held by Dennis Hogan. The authors would like to acknowledge the helpful comments from Professor Davey Smith.
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