Health Effects of Sanitation Facilities: A Bayesian Semiparametric Analysis of Compositional Data

Abstract

Summary Diarrhoeal disease is one of the leading causes of illness and death in young children: a problem exacerbated by a lack of access to safe sanitation facilities. But the effects of different types of sanitation facilities, and the relationship between their levels of coverage in an area and disease risk, remain uncertain. We specify a hierarchical model that enables us to estimate the disease risk response surface across the multi‐dimensional space of the composition of sanitation facilities in an area. This permits a non‐linear relationship between coverage of improved sanitation, differential effects by sanitation type and unobserved differences between countries. The model is used to estimate the change in risk associated with different types of sanitation facility, from which it is estimated that only increases in the coverage of sewerage and private improved sanitation facilities will achieve clinically meaningful reductions in the risk of adverse outcomes.

A comparison of traditional diarrhoea measurement methods with microbiological and biochemical indicators: A cross-sectional observational study in the Cox's Bazar displaced persons camp

“…Using the ci means command in Stata, we summarised the survey data by calculating the means and 95% confidence intervals of key demographic variables, selected risk factors for diarrhoea, and measurements of diarrhoea: broken down by season, data collection arm, and stool collection status. We defined 'having diarrhoea' for each measure of diarrhoea as: (1) answering yes to the standard survey; (2) stating diarrhoea types A or B on the pictorial survey; (3) having faecal calprotectin level over 50 mg/g and/or a faecal lactoferrin level over 7.25 mg/g for protein measurements [18,19]; or (4) stool visually being loose or watery for visual confirmation. We also summarized results of the stool tests for enteric pathogens, broken down by survey type, season, and diarrhoea status (through each measure) À with 95% confidence intervals calculated.…”

“…Considerable efforts have been made to tackle these problems by reducing the exposure of under-fives to enteric pathogens in faeces through large-scale water, sanitation, and hygiene (WASH) interventions. WASH interventions have been evaluated in observational studies and randomised trials, including three recent large-scale trials [3] , [4] , [5] , [6] , [7] , [8] , [9] . These recent trials mostly found limited evidence for the effectiveness of WASH interventions in reducing under-five diarrhoea and stunted linear growth [ 3 , 4 , 8 ].…”

“…WASH interventions have been evaluated in observational studies and randomised trials, including three recent large-scale trials [3] , [4] , [5] , [6] , [7] , [8] , [9] . These recent trials mostly found limited evidence for the effectiveness of WASH interventions in reducing under-five diarrhoea and stunted linear growth [ 3 , 4 , 8 ]. Since there is overwhelming evidence of water and environmental contamination as the primary sources of enteric pathogens which are in faeces, it is widely argued that the WASH interventions in these studies were insufficient; either in reducing exposure to enteric pathogens in faeces or in providing services to enough of the population enough of the time [10] .…”

The impact of diarrhoea measurement methods for under 5s in low‐ and middle‐income countries on estimated diarrhoea rates at the population level: A systematic review and meta‐analysis of methodological and primary empirical studies

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Effective surveillance of diarrhoea in children under 5 at the population level is required to track outbreaks, allocate public health resources and evaluate water, sanitation and hygiene (WASH) interventions [1]. However, the choice of method used to ascertain whether an episode of diarrhoea has occurred has been hypothesised to impact estimated diarrhoea rates [2,3]. If true, the results of observational and intervention studies may differ by method of measurement,

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“…The aims of the systematic review and meta-analysis were to determine: (1) the frequency of the use of the different diarrhoea measurement methods; (2) the association between passive and active surveillance methods and estimated diarrhoea rates; (3) the association between recall periods, questioning frequencies and prospective (diary) versus retrospective recall on estimated diarrhoea rates among active surveillance studies; and (4) the extent of reactivity in diarrhoea measurement.…”