Jennifer Winston

Diarrheal disease risk in rural Bangladesh decreases as tubewell density increases: a zero- inflated and geographically weighted analysis

BackgroundThis study investigates the impact of tubewell user density on cholera and shigellosis events in Matlab, Bangladesh between 2002 and 2004. Household-level demographic, health, and water infrastructure data were incorporated into a local geographic information systems (GIS) database. Geographically-weighted regression (GWR) models were constructed to identify spatial variation of relationships across the study area. Zero-inflated negative binomial regression models were run to simultaneously measure the likelihood of increased magnitude of disease events and the likelihood of zero cholera or shigellosis events. The aim of this study was to examine the effect of tubewell density on both the occurrence of diarrheal disease and the magnitude of diarrheal disease incidence.ResultsIn Matlab, households with greater tubewell density were more likely to report zero cholera or shigellosis events. Results for both cholera and shigellosis GWR models suggest that tubewell density effects are spatially stationary and the use of non-spatial statistical methods is appropriate.ConclusionsIncreasing the amount of drinking water available to households through increased density of tubewells contributed to lower reports of cholera and shigellosis events in rural Bangladesh. Our findings demonstrate the importance of tubewell installation and access to groundwater in reducing diarrheal disease events in the developing world.

Social and spatial processes associated with childhood diarrheal disease in Matlab, Bangladesh

We develop novel methods for conceptualizing geographic space and social networks to evaluate their respective and combined contributions to childhood diarrheal incidence. After defining maternal networks according to direct familial linkages between females, and road networks using satellite imagery of the study area, we use a spatial econometrics model to evaluate the significance of correlation terms relating childhood diarrheal incidence to the incidence observed within respective networks. Disease was significantly clustered within road networks across time, but only inconsistently correlated within maternal networks. These methods could be widely applied to systems in which both social and spatial processes jointly influence health outcomes.

Geographic analysis of individual and environmental risk factors for hypospadias births.

BACKGROUND Hypospadias is a relatively common birth defect affecting the male urinary tract. We explored the etiology of hypospadias by examining its spatial distribution in North Carolina and the spatial clustering of residuals from individual and environmental risk factors. METHODS We used data collected by the North Carolina Birth Defects Monitoring Program from 2003 to 2005 to estimate local Morans I statistics to identify geographic clustering of overall and severe hypospadias, using 995 overall cases and 16,013 controls. We conducted logistic regression and local Morans I statistics on standardized residuals to consider the contribution of individual variables (maternal age, maternal race/ethnicity, maternal education, smoking, parity, and diabetes) and environmental variables (block group land cover) to this clustering. RESULTS Local Morans I statistics indicated significant clustering of overall and severe hypospadias in eastern central North Carolina. Spatial clustering of hypospadias persisted when controlling for individual factors, but diminished somewhat when controlling for environmental factors. In adjusted models, maternal residence in a block group with more than 5% crop cover was associated with overall hypospadias (odds ratio = 1.22; 95% confidence interval = 1.04-1.43); that is living in a block group with greater than 5% crop cover was associated with a 22% increase in the odds of having a baby with hypospadias. Land cover was not associated with severe hypospadias. CONCLUSION This study illustrates the potential contribution of mapping in generating hypotheses about disease etiology. Results suggest that environmental factors including proximity to agriculture may play some role in the spatial distribution of hypospadias. Birth Defects Research (Part A) 100:887-894, 2014.

Protective benefits of deep tube wells against childhood diarrhea in Matlab, Bangladesh.

OBJECTIVES We investigated whether deep tube wells installed to provide arsenic-free groundwater in rural Bangladesh have the added benefit of reducing childhood diarrheal disease incidence. METHODS We recorded cases of diarrhea in children younger than 5 years in 142 villages of Matlab, Bangladesh, during monthly community health surveys in 2005 and 2006. We surveyed the location and depth of 12,018 tube wells and integrated these data with diarrhea data and other data in a geographic information system. We fit a longitudinal logistic regression model to measure the relationship between childhood diarrhea and deep tube well use. We controlled for maternal education, family wealth, year, and distance to a deep tube well. RESULTS Household clusters assumed to be using deep tube wells were 48.7% (95% confidence interval = 27.8%, 63.5%) less likely to have a case of childhood diarrhea than were other household clusters. CONCLUSIONS Increased access to deep tube wells may provide dual benefits to vulnerable populations in Matlab, Bangladesh, by reducing the risk of childhood diarrheal disease and decreasing exposure to naturally occurring arsenic in groundwater.

Impact evaluation of the Urban Health Initiative in urban Uttar Pradesh, India

Objectives The Urban Health Initiative (UHI) was initiated in 2009 with the goal of increasing family planning (FP) use among the poor in urban areas of Uttar Pradesh, India. The Measurement, Learning & Evaluation project (MLE) was tasked with rigorous impact evaluation of the UHI. This paper presents the impact evaluation findings of the UHI program. Study design The MLE design includes a longitudinal sample of women and health facilities with baseline (2010) and endline (2014) data collection in six cities in Uttar Pradesh, India. At baseline, samples representative of women in each city were selected with oversampling of the poor. Eighty-four percent of women interviewed at baseline were reinterviewed 4 years later at endline. The longitudinal data support a within/fixed-effects approach to identification of program impact on changes in modern FP use. Results Impact evaluation results show significant effects of exposure to both demand and supply side program activities. In particular, women exposed to brochures (marginal effect: 6.96, p < .001), billboards/posters/wall hangings (marginal effect: 2.09, p < .05), and FP on the television (marginal effect: 2.46, p < .001) were significantly more likely to be using a modern method at endline. In addition, we found borderline significance for being exposed to a community health worker (marginal effect: 1.66, p < .10) and living close to an improved public and private supply environment where UHI undertook activities (marginal effects and p values: 2.48, p < .05 and 1.56, p < .10, respectively). Conclusions UHI program activities were designed to complement the Government of Indias strategies aimed at ensuring access to and provision of FP to urban poor populations. The effective demand- and supply-side strategies of the UHI program are therefore likely to be sustainable and scalable to other urban areas in India. Implications statement Findings from this study are important for designing sustainable and scalable FP strategies for urban India where increases in FP use will be relevant for meeting international FP targets.

Evaluation of the Nigerian Urban Reproductive Health Initiative (NURHI) Program

Abstract Gaps remain in understanding whether family planning (FP) programs can change urban womens FP behaviors. Even less is known about what works among poor urban women. This article presents results of the impact evaluation of the Nigerian Urban Reproductive Health Initiative (NURHI). Findings are based on recently collected longitudinal data from women and facilities in six cities in Nigeria. Over the four‐year follow‐up period, there was an increase of about ten percentage points in modern method use. Impact evaluation analyses using fixed‐effects regression methods indicate that both demand‐ and supply‐side program activities increased modern method use. Radio, television, community events, and living near program‐enrolled health facilities all significantly increased modern method use or were related to a desire for no more children among all women and among poor women. Results are discussed with an eye toward the design and scale‐up of future family planning programs in urban Nigeria and elsewhere in sub‐Saharan Africa.

The Senegal urban reproductive health initiative: a longitudinal program impact evaluation

Objectives This paper presents the impact of key components of the Senegal Urban Reproductive Health Initiative, including radio, television, community-based activities, Muslim religious-leader engagement and service quality improvement on modern contraceptive use by all women and the sub-sample of poor women. Study design This study uses baseline (2011) and endline (2015) longitudinal data from a representative sample of urban women first surveyed in 2011 to examine the impact of the Initiatives demand- and supply-side activities on modern contraceptive use. Results By endline, there was increased exposure to radio and television programming, religious leaders speaking favorably about contraception, and community-based initiatives. In the same period, modern contraceptive use increased from 16.9% to 22.1% with a slightly larger increase among the poor (16.6% to 24.1%). Multivariate analyses demonstrate that women exposed to community-based activities were more likely to use modern contraception by endline (marginal effect (ME): 5.12; 95% confidence interval (CI): 2.50–7.74) than those not exposed. Further, women living within 1 km of a facility with family planning guidelines were more likely to use (ME: 3.54; 95% CI: 1.88–5.20) than women without a nearby facility with guidelines. Among poor women, community-based activities, radio exposure (ME: 4.21; 95% CI: 0.49–7.93), and living close to program facilities (ME: 4.32; 95% CI: 0.04–8.59) impacted use. Conclusions Community-based activities are important for reaching urban women, including poor women, to achieve increased contraceptive use. Radio programming is also an important tool for increasing demand, particularly among poor women. Impacts of other program activities on contraceptive use were modest. Implications This study demonstrates that community-based activities led to increased modern contraceptive use among all women and poor women in urban Senegal. These findings can inform future programs in urban Senegal and elsewhere in francophone Africa.

Women's decision-making and uptake of services to prevent mother-to-child HIV transmission in Zambia

ABSTRACT Womens empowerment is associated with engagement in some areas of healthcare, but its role in prevention of mother-to-child HIV transmission (PMTCT) services has not been previously considered. In this secondary analysis, we investigated the association of womens decision-making and uptake of health services for PMTCT. Using data from population-based household surveys, we included women who reported delivery in the 2-year period prior to the survey and were HIV-infected. We measured a womans self-reported role in decision-making in her own healthcare, making of large purchases, schooling of children, and healthcare for children. For each domain, respondents were categorized as having an “active” or “no active” role. We investigated associations between decision-making and specific steps along the PMTCT cascade: uptake of maternal antiretroviral drugs, uptake of infant HIV prophylaxis, and infant HIV testing. We calculated unadjusted and adjusted odds ratios via logistic regression. From March to December 2011, 344 HIV-infected mothers were surveyed and 276 completed the relevant survey questions. Of these, 190 (69%) took antiretroviral drugs during pregnancy; 175 (64%) of their HIV-exposed infants received antiretroviral prophylaxis; and 160 (58%) had their infant tested for HIV. There was no association between decision-making and maternal or infant antiretroviral drug use. We observed a significant association between decision-making and infant HIV testing in univariate analyses (OR 1.56–1.85; p < 0.05); however, odds ratios for the decision-making indicators were no longer statistically significant predictors of infant HIV testing in multivariate analyses. In conclusion, women who reported an active role in decision-making trended toward a higher likelihood of uptake of infant testing in the PMTCT cascade. Larger studies are needed to evaluate the impact of empowerment initiatives on the PMTCT service utilization overall and infant testing in particular.

Estimated Maternal Pesticide Exposure from Drinking Water and Heart Defects in Offspring

Our objective was to examine the relationship between estimated maternal exposure to pesticides in public drinking water and the risk of congenital heart defects (CHD). We used mixed-effects logistic regression to analyze data from 18,291 nonsyndromic cases with heart defects from the Texas Birth Defects Registry and 4414 randomly-selected controls delivered in Texas from 1999 through 2005. Water district-level pesticide exposure was estimated by linking each maternal residential address to the corresponding public water supply district’s measured atrazine levels. We repeated analyses among independent subjects from the National Birth Defects Prevention Study (NBDPS) (1620 nonsyndromic cases with heart defects and 1335 controls delivered from 1999 through 2005). No positive associations were observed between high versus low atrazine level and eight CHD subtypes or all included heart defects combined. These findings should be interpreted with caution, in light of potential misclassification and relatively large proportions of subjects with missing atrazine data. Thus, more consistent and complete monitoring and reporting of drinking water contaminants will aid in better understanding the relationships between pesticide water contaminants and birth defects.

Quantifying bias between reported last menstrual period and ultrasonography estimates of gestational age in Lusaka, Zambia

To quantify differences in assessing preterm delivery when calculating gestational age from last menstrual period (LMP) versus ultrasonography biometry.