This paper examines the changing patterns of knowledge, attitude and use of traditional methods of contraception, compared to modern methods, over the last five contraceptive prevalence surveys in Bangladesh (1981–91). The results show that knowledge of at least one method of family planning is universal in Bangladesh and usage is higher at all ages for women who are using modern methods than for those who are using traditional methods. Educated women and those in employment are more likely to use modern contraceptive methods.

In a case-control study among the urban poor of Dhaka, Bangladesh, the association of maternal education and family income with severity of disease due to diarrhoea in children was examined. After adjusting for family income, 7 or more years of school education was associated with 54% reduced risk of severe disease as indicated by the presence of dehydration. Income in the uppermost quartile of this population, independently of maternal education, was associated with 41% reduced risk of severe disease compared to the lowest quartile. In the logistic regression model the effect of maternal education remained high after adjustment for several confounders. Based on the concept that socioeconomic variables operate through a set of proximate variables it is contended that maternal education, independently of economic power, through its impact on disease from acute diarrhoea, favourably influences child survival.

There are many different questions about intelligence that easily become confused. They concern its measurement, its psychological basis (if any), its heritability and its relevance to human group differences. Even a discussion of the importance of intelligence could range widely. (1) The evolution of intelligence might consider what selection pressures generate and maintain the higher levels of intelligence that humans are generally thought to possess. (2) The persistence of individual differences in human intelligence could consider whether such differences serve some ‘group’ function in establishing clear bases for social hierarchy: individuals might differ just because intelligence is irrelevant to fertility under conditions of social hierarchy. Or the differences might be temporary, because Western social hierarchies depend on intelligence differences that they will soon undermine. (3) Is intelligence an explanatory concept in psychology? Or must attribution of scholastic or other successes to ‘intelligence’ always yield to further analyses that somehow break down intelligence into hypothetical ‘components’? (4) Educational relevance might be the issue: is it important to take intelligence differences into account when deciding on how to educate children? (5) Or the concern might be with democratic sentiment and the importance people attach to intelligence for themselves and in their spouses and children.

The determinants of modern contraceptive use in traditional populations are analysed in married women aged 30–44 living in the province of Marrakech (Morocco). Women who have never used contraception have smaller family sizes than those who do: the number of live children (or live births) is the variable with maximum predictive power on contraceptive use, while child mortality is the main inhibiting factor. The probability of contraceptive use increases with female age at marriage and decreases with the woman's age, indicating a generational change in reproductive behaviour. The socioeconomic variables education, employment and residence, have no significant independent predictive character on contraceptive use, although the interaction between education and residence does. The paper evaluates the hypothesis that traditional populations in the initial phase of their demographic transition resort to modern contraception in order to stop childbearing, when they have reached a desired number of children, rather than to space births or reduce their fertility.

The effects of selected socioeconomic factors on basic competencies of children in Bangladesh were studied using primary data on 2520 children from all over the country. The residence of the child, years of schooling, parental education and economic status of the household were found to be important determinants of basic competencies of children.

This paper investigates variations in the strength and structure of familial association in neonatal mortality risks in four populations; Bolivia, Kenya, Peru, and Tanzania. Exploratory analyses of the structure of the familial association are presented for each population. Random effects logistic models are then used to estimate the strength of familial association in neonatal mortality risks using a standard set of control variables. The results suggest that the strength of familial association in neonatal mortality risks is quite similar in these four populations which would be consistent with a biological explanation for the association. However, some differences were found, particularly in the form of the association in Peru, which may suggest at least a small role of other factors.

Successes in science tend to be successful attempts at reduction and causal interaction. The reduction of the interaction of bodies to the laws of motion and the reduction of chemical phenomena to elements and their interactions are good examples. In these cases reductionism leads to observed phenomena being explained by a relatively small number of basic concepts and the laws which govern the interaction of the concepts. The spectrum of inquiry that stretches from common sense to scientific psychology is infused with a tendency toward reductionism. Hippocrates and Galen originated and developed, respectively, the notion that temperamental differences might be reducible to the amounts of four bodily fluids, or humours (black bile, yellow bile, blood and phlegm), that a person produced. Astrologers reduced stable personality differences to the positions of the stars and planets at the time of birth. And differential psychologists have reduced the personality trait adjectives contained in the lexicon to about five major dimensions.

This study examines the relationship between family planning, perceived availability of contraceptives, and sociodemographic factors in rural Bangladesh. Data are from the 1990 KAP survey in the Matlab treatment and comparison areas, using a sample of about 8500 married women of reproductive age. The contraceptive prevalence rate was 57% in the treatment area but substantially lower in the comparison area where mainly traditional methods of family planning were used by women who did not know of a source of supply of contraceptives. Education has no effect on contraceptive use in the treatment area but in the comparison area, modest but consistent differentials in use by level of education were found. Number of living children is the best predictor for contraceptive use, followed by number of living sons, and the attitude of respondents and their husbands towards family planning.

With an unequalled contraceptive prevalence rate in sub-Saharan Africa, of 43% among currently married women in Zimbabwe, the Central Statistical Office (1989) observed that fertility has declined sharply in recent years. Using data from several surveys on Zimbabwe, especially the birth histories of the Zimbabwe Demographic and Health Survey, this study examines fertility trends in Zimbabwe. The results show that the fertility decline in Zimbabwe is modest and that the decline is concentrated among high order births. Multivariate analysis did not show a statistically significant effect of contraception on fertility, partly because a high proportion of Zimbabwean women in the reproductive age group never use contraception due to prevailing pronatalist attitudes in the country.

It has long been known that people who have high scores on intelligence tests are also relatively fast at simple laboratory tests of ‘mental speed’ (Woodrow, cited in Woodworth, 1946). When first observed these correlations attracted little interest because, though ubiquitous, they are very modest, accounting for only 3–9% of variance between individuals (Sternberg, R. J., 1977). Correlations between intelligence test scores (TSs) and speed of performance on simple tasks were seen as less interesting than equally strong associations between TSs and performance on simple tests of memory and learning (Woodrow, 1938). The idea that intelligence can be defined as the capacity to learn new skills seemed a more fruitful guide to the development of individual differences in competence (Woodrow, 1946). Further, since scores on most intelligence tests represent the number of problems correctly solved within a time limit, it did not seem remarkable that people who can solve complex problems quickly should also be able to make simple decisions fast. Finally, evidence accumulated that, speed and accuracy of problem solving can be independent; for example, the times that individuals take to solve complex spatial problems do not predict their error-rates (Egan, 1978). Consequently mental speed was seen as only one of many different demands that solving intelligence test problems make on the cognitive system. Many distinguished investigators believe that better insights can be gained into the nature of individual differences in intellectual ability by studying correlations between TSs and performance on complex tasks that demand the encoding, organisation and transformation of information in working memory or successive stages in syllogism solution (e.g. Carpenter & Just, 1989; Daneman & Carpenter, 1980; Kyllonen & Crystal, 1990; Necka, 1992; Sternberg, R. J., 1977).

This study examines the role of marriage form in infant mortality and tests the relative effects and mechanisms through which polygyny affects infant survival. A sample of infants born in the 5 years preceding the 1988 Ghana Demographic and Health Survey was used. A causal model was constructed and polygyny was found to be an important mediating factor in understanding infant survival. The findings highlight the relevance of family structure (polygyny) as an intervening factor, but also reveal the complex role of ethnicity, dietary supplement and birth interval in accounting for infant survival.

Simple measures of the biological fitness of adult men aged 25–65 years, inhabitants of the city of Wroclaw, Poland, were studied in two well-defined social groups: professionals and skilled workers. It was found that the manual workers, compared to professionals, have higher systolic and diastolic blood pressure, lower relative vital capacity, inferior flexibility of spine, poorer eye-hand co-ordination, and poorer hearing acuity. These social differences appear consistently at each age level between 25 and 65 years and tend to increase with age to the disadvantage of skilled workers.

Males have often been neglected in both family planning programmes and in surveys used to design and evaluate such programmes. A 1988 study on fertility, family planning and AIDS in Kinshasa, Zaire, provides comparable data on 3140 men and 3485 women of reproductive age which served as the basis for analysing male/female differences. The study indicated a fair degree of similarity in the attitudes, beliefs, knowledge levels and practices of men and women regarding fertility and family planning. Where they differed (e.g. on expected or ideal number of children, the desire for more children at parity 7 or above), men tended to be more pronatalist than women. The implications of the findings for future family planning programmes are discussed. Programmes should target males because of their role as decision makers within Zairian society.

Health of school age children and the Partnership for Child Development

Until recently, health programmes in developing countries have focused on infant survival and on the health of adolescents and, consequently, the health concerns of children of school age, falling between the ages of infancy and adolescence, have been neglected. The World Bank Development Report of 1993, stated a need to move beyond the focus on survival and to capture the concept that community health depends on the quality of life and opportunities for development. In response, the Partnership for Child Development was set up in 1992 to address the problem of ill-health among school-age children in the developing world.

Using lists of names of male personal telephone subscribers, isonymy was calculated within and between 29 contiguous areas in a north-to-south line extending 210 km south of Grindsted, Denmark. Each area shared some surname(s) with every other area. Isonymy was high across both the present and past borders of Denmark with Germany and was consistently lower in areas beyond 160 km south of Grindsted. Relative isonymy between areas was also smaller on average south of the present border than north of it, and smaller still for pairs of areas spanning the border. This is partly accounted for by decreases in isonymy with distance, but the slope of the logistic regression on distance is greater for the northern moiety than the southern one. Most of these findings can be traced to the influence of common surnames ending in ‘sen’, the distribution of which tends to correlate highly with isonymy. Such surnames tend to be of recent origin and to be very frequent and hence highly polygenic. Thus much of the heterogeneity is explained by surname history rather than genetic heterogeneity.

A study in Bangladesh showed that the probability of use of modern contraception by eligible family members of a household increases significantly if the household head himself is a user. Multinomial logistic regression showed that contraceptive use was also significantly related with maternal age, parity, education, socioeconomic status and experience of child mortality. Inclusion of ever use of modern contraceptives by the family head or his wife, showed family head's religiosity to be a significant predictor of use, apart from his age and parity, and after controlling for socioeconomic correlates.

Unlike other organs the energy requirement of the brain is met almost exclusively by aerobic glucose degradation (Siesjo, 1978). The energy requirement of the brain is 20–30% of the whole organism at rest, although its weight is only 2%. The energy stores in the brain are extremely small when compared with the high rate of glucose utilisation: thus the brain is reliant on a continuous glucose supply. Only about 30% of glucose is required for direct energy production; much of the remainder is used for the synthesis of amino acids, peptides, lipids and nucleic acids (Siebert, Gessner & Klasser, 1986). Thus a source of glucose is essential for the synthesis of physiologically active amines such as serotonin, noradrenaline and acetylcholine. Although it is well accepted that hypoglycaemia can result in the disruption of cognitive functioning, this is a rare phenomenon and it has usually been assumed that levels of blood glucose, within the normal range, do not influence intellectual functioning. This assumption is discussed in this paper.

Consanguineous marriages in two population samples, one rural and one urban, from Swat (Pakistan) were studied. The frequency of consanguineous marriages was found to be 37·13% and 31·11%, and mean inbreeding coefficients were calculated as 0·0168 and 0·0162, for the rural and urban populations respectively. The most frequent type of marriage was between first cousins, in both samples. Among first cousin marriages, those with father's brother's daughter were predominant. Mean inbreeding coefficient was higher for higher socioeconomic groups in both samples. Differences by ethnic and educational groups were also found. Contrary to previous studies, a significant increase in the incidence of consanguineous marriages over the years has been observed. The incidence of premature mortality was significantly higher only in the offspring of first cousin marriages. Significantly higher incidence of morbidity in the offspring of consanguineous marriages was also observed.

This paper examines the association between infant mortality of the first born and subsequent children using data from rural Bangladesh collected during the period 1971–82. It shows that birth spacing and age of mother at the time of the second birth are important predictors of the survival status of the first child. The findings are discussed in terms of policy implications.

This paper investigates the normative and behavioural dimensions of son preference in Morocco and Tunisia, using data from the Demographic and Health Surveys of the two countries. It considers three measures of son preference: (1) mothers' ideal number of children, and any preference for having more sons than daughters; (2) the desire for additional children, given their existing family; (3) reported use of contraception in relation to the existing number of children of each sex. The analyses indicate a moderate preference for sons in both countries, and suggest that this preference is somewhat stronger in Tunisia. These findings are interpreted within the cultural context of the two countries, and in particular societal notions of women's status.