Bright Lines, Risk Beliefs, and Risk Avoidance: Evidence from a Randomized Intervention in Bangladesh (original) (raw)
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Journal of Environmental Economics and Management, 2013
We conducted a randomized controlled trial in rural Bangladesh to examine how household drinking-water choices were affected by two different messages about risk from naturally occurring groundwater arsenic. Households in both randomized treatment arms were informed about the arsenic level in their well and whether that level was above or below the Bangladesh standard for arsenic. Households in one group of villages were encouraged to seek water from wells below the national standard. Households in the second group of villages received additional information explaining that lower-arsenic well water is always safer and these households were encouraged to seek water from wells with lower levels of arsenic, irrespective of the national standard. A simple model of household drinking-water choice indicates that the effect of the emphasis message is theoretically ambiguous. Empirically, we find that the richer message had a negative, but insignificant, effect on well-switching rates, but the estimates are sufficiently precise that we can rule out large positive effects. The main policy implication of this finding is that a one-time oral message conveying richer information on arsenic risks, while inexpensive and easily scalable, is unlikely to be successful in reducing exposure relative to the status-quo policy.
Journal of Development Economics, 2007
We study how effectively information induces Bangladeshi households to avoid a health risk. The response to information is large and rapid; knowing that the household's well water has an unsafe concentration of arsenic raises the probability that the household changes to another well within one year by 0.37. Households who change wells increase the time spent obtaining water fifteen-fold. We identify a causal effect of information, since incidence of arsenic is uncorrelated with household characteristics. Our door-to-door campaign provides well-specific arsenic levels without which behavior does not change.
Can information alone change behavior? Arsenic contamination of groundwater in Bangladesh
2005
We study how effectively information alone induces people to incur the cost of avoiding a risk to health. Arsenic contamination of the groundwater in Bangladesh provides an unfortunate natural experiment. We find that the response to specific information about the safety of one's well is large and rapid; having an unsafe well raises the probability that the individual changes to another well within one year by 0.5. The estimate of the impact of information is unbiased, because arsenic levels are uncorrelated with individual characteristics. Evidence suggests that a media campaign communicates general information about arsenic as effectively as does a more expensive door-to-door effort.
Subjective Risk Assessment and Reactions to Health-related Information: Evidence from Bangladesh
2009
Arsenic-contaminated drinking water is a serious public health problem in several countries, including Bangladesh. In this paper we contribute to the literature on the relationship between information provision and health seeking behavior in developing countries by using data pur-posely collected in Araihazar district, Bangladesh. We analyze the relationship between the provision of information about arsenic level of tubewell water, elicited perceptions about health risks and choice of source of drinking water. Our findings indicate widespread awareness about the health risk of arsenic as well as about the cumulative negative effects of a prolonged expo-sure. Respondents ’ perceptions of health risk are strongly increasing in the arsenic level and also help explaining the decision to switch to alternative sources of drinking water when the current source is unsafe. In addition, we describe the results of a randomized controlled trial which allows us to evaluate the impact of differe...
Environment and Development Economics, 2013
A national campaign of well testing through 2003 enabled households in rural Bangladesh to switch, at least for drinking water, from high-arsenic wells to neighboring lower arsenic wells. We study the well-switching dynamics over time by re-interviewing, in 2008, a randomly selected subset of households in the Araihazar region who had been interviewed in 2005. Contrary to concerns that the impact of arsenic information on switching behavior would erode over time, we find that not only was 2003–2005 switching highly persistent but also new switching by 2008 doubled the share of households at unsafe wells who had switched. The passage of time also had a cost: 22 per cent of households did not recall test results by 2008. The loss of arsenic knowledge led to staying at unsafe wells and switching from safe wells. Our results support ongoing well testing for arsenic to reinforce this beneficial information.
Risk Analysis, 2006
The common sense model (CSM) shows how people process information to construct representations, or mental models, that guide responses to health threats. We applied the CSM to understand how people responded to information about arsenic-contaminated well water. Constructs included external information (arsenic level and information use), experience (perceived water quality and arsenic-related health effects), representations, safety judgments, opinions about policies to mitigate environmental arsenic, and protective behavior. Of 649 surveys mailed to private well users with arsenic levels exceeding the maximum contaminant level, 545 (84%) were analyzed. Structural equation modeling quantified CSM relationships. Both external information and experience had substantial effects on behavior. Participants who identified a water problem were more likely to reduce exposure to arsenic. However, about 60% perceived good water quality and 60% safe water. Participants with higher arsenic levels selected higher personal safety thresholds and 20% reported a lower arsenic level than indicated by their well test. These beliefs would support judgments of safe water. A variety of psychological and contextual factors may explain judgments of safe water when information suggested otherwise. Information use had an indirect effect on policy beliefs through understanding environmental causes of arsenic. People need concrete information about environmental risk at both personal and environmental-systems levels to promote a comprehensive understanding and response. The CSM explained responses to arsenic information and may have application to other environmental risks.
Experts are making a major effort to find technical solutions to the serious public health problems posed by arsenic in drinking water in Bangladesh, but public education strategies receive less systematic attention. This article presents findings of a study evaluating the impact of a 1999 campaign by the 18 DistrictTowns Project to educate the public about the arsenic problem in six Bangladesh towns, where half of the population was estimated to be using arsenic-contaminated domestic water: (1) Water users were advised not to consume arsenic-affected tube-well water; (2) A simple, temporary water treatment method was recommended for those using such water, if they had no safe alternative source; (3) Caretakers of tube-wells having arsenic-free water were advised to share their water sources with others. This evaluation study, utilizing a combination of quantitative and qualitative social research methods, found those influenced by the programme to have higher awareness levels and significantly lower levels of risk behaviour than others. Yet more than half of the at-risk, programme-influenced survey respondents were found still to be drinking (57%) or cooking with (54%) arsenic-affected water. Despite the fact that the campaign did not have a satisfactory public health impact, the experience can inform future efforts to educate the Bangladeshi public about arsenic. One finding is widespread confusion about trusted tube-well water being newly labelled as 'unsafe'. Some thinkthe problem is in the hand pumps themselves. Awareness of life threatening danger from arsenic contamination was found to be low. Learning points from this experience are: the value of explaining together with water testing; giving people opportunities to ask questions; repeating messages; continuing to educate children about the serious risks of consuming surface water; conducting community-wide education programmes for people of all ages; and evaluating the impact of specific public education strategies. Respecting such principles in public information campaigns will greatly help the public to benefit from future technical developments.
Increasing Gains from Risk Information: Evidence from Arsenic in Bangladesh
2011
Few evaluations have tracked the long-run impact of public health information, especially in developing countries. We provide evidence from Bangladesh, where over one third of the population is exposed through drinking to unsafe levels of arsenic in the groundwater. About five million shallow tubewells were tested for arsenic by 2003 and several studies document significant switching away from arsenic-unsafe wells shortly after those tests. However there is little evidence to gauge whether such switching is persistent or instead many households returned to unsafe wells that are closer and that they themselves own. Here we provide novel estimates of the longer-run impacts of testing for this health crisis. In 2008, we recorded the well-switching decisions during 2005-08 of 1557 households in Araihazar Upazila who had received well-arsenic tests by 2003 and whose well switching in 2003-05 had been recorded. We find that 2003-05 switching is remarkably persistent, with few households switching again and none returning to the unsafe wells used before. We also find that switching in the longer run was almost twice as high as in the short run: over five years, 42% of households whose wells had been tested unsafe switched sources, compared with 24% who switched within two years. Thus, we find short-run evaluations of health-risk information programs can substantially underestimate their overall impact.
American Journal of Tropical Medicine and Hygiene, 2013
Arsenic (As) testing could help 22 million people, using drinking water sources that exceed the Bangladesh As standard, to identify safe sources. A cluster randomized controlled trial was conducted to evaluate the effectiveness of household education and local media in the increasing demand for fee-based As testing. Randomly selected households (N = 452) were divided into three interventions implemented by community workers: 1) fee-based As testing with household education (HE); 2) fee-based As testing with household education and a local media campaign (HELM); and 3) fee-based As testing alone (Control). The fee for the As test was US$ 0.28, higher than the cost of the test (US$ 0.16). Of households with untested wells, 93% in both intervention groups HE and HELM purchased an As test, whereas only 53% in the control group. In conclusion, fee-based As testing with household education is effective in the increasing demand for As testing in rural Bangladesh.
Water
The acceptance of newly implemented, safe drinking water options is not guaranteed. In the Khulna and Satkhira districts, Bangladesh, pond water is pathogen-contaminated, while groundwater from shallow tubewells may be arsenic- or saline-contaminated. This study aims to determine why, as well as the extent to which, people are expected to remain attached to using these unsafe water options, compared to the following four safer drinking water options: deep tubewells, pond sand filters, vendor water, and rainwater harvesting. Through 262 surveys, this study explores whether five explanatory factors (risk, attitude, norms, reliability, and habit) pose barriers to switching from unsafe to safe drinking water options or whether they could act as facilitators of such a switch. Users’ attachment to using pond water is generally low (facilitators: risk and attitude. Barrier: norms). Users are more attached to shallow tubewells (no facilitators. Barriers: reliability and habit). The safe alt...