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Fertility determinants in the oil region of Mexico.

This study analyzes fertility determinants in the oil region of Mexico, consisting of the states of Veracruz, Tabasco, and Campeche. Data are from the 1980 Mexican census and the unit of analysis is the municipio. The regression models, in which the dependent variables of children ever born and child-woman ratio are examined, reveal religious variables to be most significant, with greater fertility for non-Catholics and persons with no religion than for Catholics. Also of great importance are economic variables. Literacy and urbanization, both "classical" Mexican fertility variables, reduce fertility. There are major differences among three urban/rural and three indigenous language subsamples. Results are discussed vis-a-vis demographic theories and prior research.

Adolescent↗

Levels and correlates of maternal nutritional status in urban Bangladesh.

OBJECTIVE: To determine the levels and correlates of maternal nutritional status. DESIGN: Cross-sectional maternal weight, height, and mid-upper arm circumference (MUAC) data were correlated with sociodemographic data. SETTING: Slums of Dhaka, Bangladesh. SUBJECTS: Weight, height and MUAC were collected from a representative sample of 2417 nonpregnant mothers. Socioeconomic data such as age, education, religion and household economic status was collected from 2048 mothers; data on reproductive experiences such as number of pregnancies and number of children born alive now dead was available from 1314 mothers; and both sets of data from 1185 mothers. METHODS: Using weight, height, MUAC and body mass index (BMI) data, the levels of maternal nutritional status were estimated. Bivariate and multivariate relationships of maternal nutritional status with socioeconomic and reproductive experiences variables were examined. RESULTS: Mothers' mean weight, height, MUAC and BMI were 41.8 kg, 148.8 cm, 232.5 mm, and 18.8 respectively. In multivariate regression analyses, mothers' weight, BMI and MUAC were significantly positively correlated with mothers' years of schooling (P < 0.05) and household economic status (P < 0.01). Mothers' height was significantly positively correlated with years of schooling (P < 0.05), but not with household economic status. Maternal height and weight were significantly negatively correlated with number of child deaths (P < 0.05). CONCLUSIONS: The findings suggest a possible inter-generational effect; thus, improvement of the nutritional status of girls of this generation would improve child survival in the next generation. This, however, will require complex and long-term planning. As an interim measure, shorter mothers should be targeted for appropriate antenatal and obstetric services.

Adult↗

Health practices and indices of a poor urban population in Indonesia. Part II: Immunization, nutrition, and incidence of diarrhea.

This second section in a two-part study of health indices and practices among a poor urban population in Indonesia focuses on problems related to immunization, nutrition, and incidence of diarrhea. Through a survey of 690 mothers and 593 children in two slum communities in Jakarta, we found that 1) 65% of the children were mildly to severely malnourished according to Gomez criteria, with malnutrition most prevalent among the poorest; 2) 75% of the mothers reported exclusive breastfeeding of their infants during the first four months after birth, but breastfeeding decreased sharply with increasing socioeconomic status; 3) of the 19% of one- to three-year-old children who were incompletely immunized, most were likely to be missing their measles and DPT3 immunizations; and 4) 28% of the mothers reported that at least one of their under-three-year-old children had diarrhea in the last month, with frequency of reporting highest among poor mothers and those using water from vendors. We concluded that selective interventions should be accompanied by development of a comprehensive health infrastructure that permits uninterrupted service delivery and follow up of those identified as high risk. Such a comprehensive primary health care system should be part of a multisectoral development strategy.

Breast Feeding↗

Who consults and where? Sociocultural differentiation in access to health care in urban Africa.

Sociocultural differentiation in health behaviour was studied among 500 mothers randomly chosen in the suburban area of Dakar, Senegal. Variables were age, marital status, educational level, socioeconomic conditions, urban experience, town integration, village attachment, social insurance, ethnic group and disease categories. Access to health care was considered for the last illness of the mother and her youngest child under five. Town integration and disease category (and social insurance for children) were the only variables correlated with the number of consultations. Socioeconomic level and social insurance (and educational level for mothers) were associated with preference for private rather than public health systems.

Adult↗

Civil war and the spread of AIDS in Central Africa.

Using ordinary least squares regression techniques this paper demonstrates, for the first time, that the classic association of war and disease substantially accounts for the presently observed geographical distribution of reported clinical AIDS cases in Uganda. Both the spread of HIV 1 infection in the 1980s, and the subsequent development of AIDS to its 1990 spatial pattern, are shown to be significantly and positively correlated with ethnic patterns of recruitment into the Ugandan National Liberation Army (UNLA) after the overthrow of Idi Amin some 10 years earlier in 1979. This correlation reflects the estimated mean incubation period of 8-10 years for HIV 1 and underlines the need for cognizance of historical factors which may have influenced current patterns of AIDS seen in Central Africa. The findings may have important implications for AIDS forecasting and control in African countries which have recently experienced war. The results are compared with parallel analyses of other HIV hypotheses advanced to account for the reported geographical distribution of AIDS in Uganda.

Acquired Immunodeficiency Syndrome↗

Determinants of infant and early childhood mortality in Cameroon: the role of socioeconomic factors, housing characteristics, and immunization status.

This study examines factors impinging on the survival of children in Cameroon using longitudinal data collected by the United Nations Demographic Training and Research Institute of Yaoundé, Cameroon. It deals especially with the role of socioeconomic factors (mother's education, employment, marital status, ethnicity, and household income), housing characteristics (construction materials, power source, source of water supply, extent of crowding), and immunization status on infant and child mortality. Two-state parametric and nonparametric hazards models for the risk of death at any time within the course of the study are used, with and without accounting for unmeasured heterogeneity. Overall, overcrowding has robust deleterious effects on infant and child survival. As regards the effects of socioeconomic variables, the robustness of the effects of household income and ethnic differentials are unchanged, even after controlling for unmeasured heterogeneity; the deleterious effects of marital status are also apparent, but these effects are largely explained by unmeasured covariates. The data also suggest that the protective effects of full immunization status are robust and not contaminated by confounding factors, at least in the first 16 months of life. These findings provide solid ground to support immunization programs and efforts as a means to reduce significantly infant and child mortality.

Cameroon↗

Seasonality in tropical AIDS: a geographical analysis.

This paper presents evidence that the growth rate of the AIDS epidemic at the district level in Uganda, Central Africa, displays a seasonally recurring geographical pattern, with epidemic acceleration in some areas of the country in the first 8 months of each year. The spatial and temporal variations in acceleration appear to be correlated with the predominant agricultural systems in different parts of Uganda. Based upon the frequently hypothesized relationship between malnourishment and the progression to clinical AIDS in HIV-infected people, it is suggested that the variations in epidemic speed reflect the seasonal patterns of nutritional deficiency which occur under some tropical agricultural systems. These preliminary findings require further verification since they have important implications for directing nutrition-related remedial responses to the AIDS epidemic in tropical countries where malnutrition and endemic HIV infection coincide.

Acquired Immunodeficiency Syndrome↗

Associations between social and environmental factors and perinatal mortality in Jamaica.

Social and environmental factors in Jamaica were compared between 9919 mothers delivering in a 2-month period a singleton who survived the early neonatal period and 1847 mothers who were delivered of a singleton perinatal death in a contiguous 12-month period. Logistic regression showed independent positive statistically significant increased odds of having a perinatal death among mothers who lived in rural parishes, older mothers (aged 30 +), single parents, no other children in the household, large number of adults in the household, mother unemployed, the major wage earner of the household not being in a managerial, professional or skilled non-manual occupation, the household not having sole use of toilet facilities, smaller mothers and those classified as obese or undernourished. Variations were found for different categories of death. Intrapartum asphyxia deaths were not related to union (marital) status, occupation of major wage earner, number of adults nor to the use of the toilet. Antepartum fetal deaths did not vary significantly with occupation of major wage earner or maternal height, but did show a relationship with maternal education, mothers with lowest levels having reduced risk. Deaths from immaturity were significantly related only to occupation of major wage earner, number of children in the household, number of social amenities available (negative relationships) and maternal age (< 17 at highest risk). In conclusion there was little to indicate that social deprivation per se was related to perinatal death, although specific features of the environment showed strong relationships.

Adolescent↗

Infant mortality and crisis in Mexico.

Data derived from the Encuesta Nacional de Fecundidad y Salud (ENFES) confirm that overall levels of infant mortality in Mexico have been steadily declining. However, a more specific analysis furnishes evidence that this decline has occurred at varying rates within different social groups, reflecting an increase in social inequalities. The analytical strategy used in this article leads to three basic conclusions: (1) the impact of the economic crisis on infant mortality is reflected not in a reversal of the declining trend but an increase in social inequalities; (2) certain variables universally accepted as determinants of infant mortality, such as mother's education, seem nonsignificant for some social sectors; and (3) certain biodemographic characteristics assumed to have a uniform mortality-related behavior vary among sectors, suggesting that even these constants are determined by social factors.

Educational Status↗

Birthweights in Goroka and Kainantu Hospitals.

Birthweight data for 4474 live, healthy, singleton, full-term births of 2000g or over were analysed. The mean birthweights were 3136 +/- 445g at Goroka, and 3106 +/- 473g at Kainantu. Birthweights varied with sex, region of maternal origin, season and birth order, but not with year. Significant influences on Goroka birthweight values were, in order of importance, birth order, sex and season.

Birth Order↗

Analysis of phosphorescence in heterogeneous systems using distributions of quencher concentration.

A continuous distribution approach, instead of the traditional mono- and multiexponential analysis, for determining quencher concentration in a heterogeneous system has been developed. A mathematical model of phosphorescence decay inside a volume with homogeneous concentration of phosphor and heterogeneous concentration of quencher was formulated to obtain pulse-response fitting functions for four different distributions of quencher concentration: rectangular, normal (Gaussian), gamma, and multimodal. The analysis was applied to parameter estimates of a heterogeneous distribution of oxygen tension (PO2) within a volume. Simulated phosphorescence decay data were randomly generated for different distributions and heterogeneity of PO2 inside the excitation/emission volume, consisting of 200 domains, and then fit with equations developed for the four models. Analysis using a monoexponential fit yielded a systematic error (underestimate) in mean PO2 that increased with the degree of heterogeneity. The fitting procedures based on the continuous distribution approach returned more accurate values for parameters of the generated PO2 distribution than did the monoexponential fit. The parameters of the fit (M = mean; sigma = standard deviation) were investigated as a function of signal-to-noise ratio (SNR = maximum signal amplitude/peak-to-peak noise). The best-fit parameter values were stable when SNR > or = 20. All four fitting models returned accurate values of M and sigma for different PO2 distributions. The ability of our procedures to resolve two different heterogeneous compartments was also demonstrated using a bimodal fitting model. An approximate scheme was formulated to allow calculation of the first moments of a spatial distribution of quencher without specifying the distribution. In addition, a procedure for the recovery of a histogram, representing the quencher concentration distribution, was developed and successfully tested.

Light↗

Age-prevalence and household clustering of Strongyloides stercoralis infection in Jamaica.

The epidemiology of Strongyloides stercoralis was studied in families of clinical (reference) cases and their neighbours at endemic foci in Jamaica. Thirteen foci were studied based on the place of residence of a reference case. For each household of a reference case, the 4 most proximal neighbourhood households (spatial controls) were included in the study. Out of 312 persons contacted 244 were followed up using questionnaires, stool examination and serology. Prevalence of infection based on stool examination was 3.5% and on ELISA 24.2%. Prevalence increased with age but was not related to gender. Reference cases were significantly older than the general study population. The prevalence of infection based on both serology and stool examination was significantly higher in reference than in neighbouring households (the reference cases, themselves, were not included in the analysis). Furthermore, prevalence of infection was highest among persons who shared a bedroom with a reference case and decreased significantly with increasing spatial separation. This is indicative of close contact transmission which has not been previously shown for a geohelminth, but which is common among microparasites.

Adolescent↗

Assessment of the spatial occurrence of childhood leukaemia mortality using standardized rate ratios with a simple linear Poisson model.

Reports of a suspected cluster of childhood leukaemia cases in West Central Phoenix have led to a number of epidemiological studies in the geographical area. We report here on a death certificate-based mortality study, which indicated an elevated rate ratio of 1.95 during 1966-1986, using the remainder of the Phoenix standard metropolitan statistical area (SMSA) as a comparison region. In the process of analysing the data from this study, a methodology for dealing with denominator variability in a standardized mortality ratio was developed using a simple linear Poisson model. This new approach is seen as being of general use in the analysis of standardized rate ratios (SRR), as well as being particularly appropriate for cluster investigations.

Adolescent↗

[Cartography of epidemiologic data. The principal methods of making continuous data discrete and their importance in cartographic representation].

The cartographic representation of continuous quantitative data is often required in studies of the spatial distribution of health indicators. It imposes a succession of choices which directly affect the result obtained. The conversion of continuous data to discrete data is one of the most important steps in the development of epidemiological maps. This article presents the methods currently used to make data discrete, discusses the advantages and disadvantages of each method and assesses their appropriateness for various situations. As an example, and for comparison purposes, we mapped the same series of statistics (relative rates of avoidable male deaths, "associated with the health care system", for "employment zones" in France from 1988 to 1992), using each of the methods discussed.

Algorithms↗