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Water fluoridation is a controversial issue in public health. Despite the uncertainty regarding its efficacy and safety, health officials continue to communicate it as 'unequivocally' safe and effective. Our focus is on how health officials and policy-makers in Israel frame the issue of water fluoridation in terms of certainty while promoting a mandatory fluoridation policy. According to van Asselt and Vos, the uncertainty paradox describes situations in which uncertainty is acknowledged, but the role of science is framed as providing certainty. Our study is an analysis of documents and media articles emphasizing the paradoxical language used by official representatives on the controversial topic of fluoridation. A central contribution of this study is that we coin the term 'uncertainty bias,' in which policy-makers do exactly what they accuse laypeople of doing, framing uncertainty in biased terms. We found that in order to establish mandatory regulation , health ministry officials expressed information in an unbalanced format, promoting the topic of fluoridation by framing it in exclusively positive terms. This study does not focus on the practice of water fluoridation per se, and is not intended to decide for or against it, but rather, to explore how the debate regarding it is communicated. Understanding this particular case can shed light on how other controversial topics are transformed into health policy that is characterized in equivocal terms.
To read the full-text of this research, you can request a copy directly from the authors.
... Since its inception, this pattern of bias has been de rigeur in the handful of the primarily English speaking countries that practice fluoridation. Emphasis on poor quality science is part of this pattern, a pattern that is continuing in the 21st century [1,10,46,. ...
Municipal fluoridation was a mid-twentieth century innovation based on the medical hypothesis that consuming low doses of fluoride when young provided protection against cavities with only a small risk of mild dental fluorosis, a cosmetic effect. In the 21st century, more than half of American teens are afflicted by dental fluorosis with approximately one in five having moderate to severe dental fluorosis in at least two teeth. Scientific literature since the 1990s has found that even low doses of fluoride adversely affect cognitive-behavioral development and that deficits are correlated with the severity of dental fluorosis in afflicted individuals. Evidence of neurotoxic impact from low dose systemic exposure to fluoride prompted an investigation by a branch of the governmental agency that has promoted fluoridation policy since its 1940′s inception. This review identifies ten significant flaws in the design of an animal experiment conducted by the U.S. National Toxicology Program as part of that investigation into the neurotoxic impact of systemic prenatal and postnatal fluoride exposure. The authors hypothesize that organizational bias can and does compromise the integrity of fluoride research.
Within a neoliberal environment that prioritizes the individual over the community, understanding challenges associated with advancing population-level or universal interventions is important if public health is to remain a relevant collective institution. As a case example, we considered a controversial public health intervention – community water fluoridation – and undertook focus groups with dental hygienists in Calgary, Alberta, Canada, to explore ways that fluoridation (a population-level intervention) is understood and discussed in their day-to-day clinical interactions as frontline cavity prevention experts. The overarching theme in our data centered around a key public health conundrum – that is, the difficulties reconciling individual and community- or population-level responsibility for health. Dental hygienists wrestled with the transdisciplinary nature of population-level public health interventions; acknowledged changing roles and relationships between themselves and their patients; and revealed dissonance in their own beliefs about individualism and collectivism in health. Our findings shed light on communication challenges where public health information delivery intersects with clinical encounters, in the context of empowered and knowledgeable health consumers. A challenge for the public health community is to reflect on how to better address a contemporary public’s reasonable information requests and negotiate the clash between individualism and collectivism more effectively.
Iodine deficiency disorders (IDD) and their attendant effects on human development, perinatal mortality and intellectual dysfunction are a major nutrition and public health problem worldwide, with Ethiopia counted among the top iodine-deficient countries. Despite the passing of new legislation in 2011 under the National Nutrition Programme and subsequent increase in the availability of iodized salt, the eradication of IDD in Ethiopia remains a significant challenge. This paper critically reviews the recent published data on iodine-status in Ethiopia as a basis for formulating future research and policy initiatives.
We performed a structural search for IDD studies in Ethiopia for all population groups published after the year 2000.
Twenty four studies reported national and regional data giving a national total goiter rate above 35.8 % in women, with rates close to 60 % in four regional states, and an estimated prevalence of IDD ranging from 0.4 to 66.3 % depending on region. The prevalence of goiter in children was 35 %, but was as high as 71 % in the South Nations Nationalities and Peoples Region. The problem persists despite the widespread availability of iodized salt.
Eradicating IDD in Ethiopia will require concerted efforts including the close evaluation of intervention programs through regular, nation-wide monitoring of IDD and salt-iodization coverage. Salt iodization became mandatory in Ethiopia in 2011 and despite significant progress, the current level of eradicating IDD could be improved. Prospective and controlled intervention studies to evaluate biomarkers of thyroid function and cognitive outcomes will help to monitor and improve eradication efforts. Ascertaining and improving health and development in the most vulnerable populations of women and children is a priority that may be advanced through a greater investment in outreach and education.
Dental caries is a major public health problem in most industrialised countries, affecting 60% to 90% of school children. Community water fluoridation was initiated in the USA in 1945 and is currently practised in about 25 countries around the world; health authorities consider it to be a key strategy for preventing dental caries. Given the continued interest in this topic from health professionals, policy makers and the public, it is important to update and maintain a systematic review that reflects contemporary evidence.
To evaluate the effects of water fluoridation (artificial or natural) on the prevention of dental caries.
To evaluate the effects of water fluoridation (artificial or natural) on dental fluorosis.
We searched the following electronic databases: The Cochrane Oral Health Group's Trials Register (to 19 February 2015); The Cochrane Central Register of Controlled Trials (CENTRAL; Issue 1, 2015); MEDLINE via OVID (1946 to 19 February 2015); EMBASE via OVID (1980 to 19 February 2015); Proquest (to 19 February 2015); Web of Science Conference Proceedings (1990 to 19 February 2015); ZETOC Conference Proceedings (1993 to 19 February 2015). We searched the US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization's WHO International Clinical Trials Registry Platform for ongoing trials. There were no restrictions on language of publication or publication status in the searches of the electronic databases.
For caries data, we included only prospective studies with a concurrent control that compared at least two populations - one receiving fluoridated water and the other non-fluoridated water - with outcome(s) evaluated at at least two points in time. For the assessment of fluorosis, we included any type of study design, with concurrent control, that compared populations exposed to different water fluoride concentrations. We included populations of all ages that received fluoridated water (naturally or artificially fluoridated) or non-fluoridated water.
Data collection and analysis
We used an adaptation of the Cochrane 'Risk of bias' tool to assess risk of bias in the included studies.
We included the following caries indices in the analyses: decayed, missing and filled teeth (dmft (deciduous dentition) and DMFT (permanent dentition)), and proportion caries free in both dentitions. For dmft and DMFT analyses we calculated the difference in mean change scores between the fluoridated and control groups. For the proportion caries free we calculated the difference in the proportion caries free between the fluoridated and control groups.
For fluorosis data we calculated the log odds and presented them as probabilities for interpretation.
A total of 155 studies met the inclusion criteria; 107 studies provided sufficient data for quantitative synthesis.
The results from the caries severity data indicate that the initiation of water fluoridation results in reductions in dmft of 1.81 (95% CI 1.31 to 2.31; 9 studies at high risk of bias, 44,268 participants) and in DMFT of 1.16 (95% CI 0.72 to 1.61; 10 studies at high risk of bias, 78,764 participants). This translates to a 35% reduction in dmft and a 26% reduction in DMFT compared to the median control group mean values. There were also increases in the percentage of caries free children of 15% (95% CI 11% to 19%; 10 studies, 39,966 participants) in deciduous dentition and 14% (95% CI 5% to 23%; 8 studies, 53,538 participants) in permanent dentition. The majority of studies (71%) were conducted prior to 1975 and the widespread introduction of the use of fluoride toothpaste.
There is insufficient information to determine whether initiation of a water fluoridation programme results in a change in disparities in caries across socioeconomic status (SES) levels.
There is insufficient information to determine the effect of stopping water fluoridation programmes on caries levels.
No studies that aimed to determine the effectiveness of water fluoridation for preventing caries in adults met the review's inclusion criteria.
With regard to dental fluorosis, we estimated that for a fluoride level of 0.7 ppm the percentage of participants with fluorosis of aesthetic concern was approximately 12% (95% CI 8% to 17%; 40 studies, 59,630 participants). This increases to 40% (95% CI 35% to 44%) when considering fluorosis of any level (detected under highly controlled, clinical conditions; 90 studies, 180,530 participants). Over 97% of the studies were at high risk of bias and there was substantial between-study variation.
There is very little contemporary evidence, meeting the review's inclusion criteria, that has evaluated the effectiveness of water fluoridation for the prevention of caries.
The available data come predominantly from studies conducted prior to 1975, and indicate that water fluoridation is effective at reducing caries levels in both deciduous and permanent dentition in children. Our confidence in the size of the effect estimates is limited by the observational nature of the study designs, the high risk of bias within the studies and, importantly, the applicability of the evidence to current lifestyles. The decision to implement a water fluoridation programme relies upon an understanding of the population's oral health behaviour (e.g. use of fluoride toothpaste), the availability and uptake of other caries prevention strategies, their diet and consumption of tap water and the movement/migration of the population. There is insufficient evidence to determine whether water fluoridation results in a change in disparities in caries levels across SES. We did not identify any evidence, meeting the review's inclusion criteria, to determine the effectiveness of water fluoridation for preventing caries in adults.
There is insufficient information to determine the effect on caries levels of stopping water fluoridation programmes.
There is a significant association between dental fluorosis (of aesthetic concern or all levels of dental fluorosis) and fluoride level. The evidence is limited due to high risk of bias within the studies and substantial between-study variation.
This study examines vaccination hesitancy or refusal following the 2013 polio
outbreak in Israel, based on two theoretical models. The first is Sandman’s theoretical
model, which holds that risk perception is comprised of hazard plus outrage.
The second model is the affect heuristic that explains the risk/benefit
confounding. It aims to expose the barriers that inhibited parental compliance
with OPV vaccination for their children. The study employed mixed methods –
a questionnaire survey (n = 197) and content analysis of parents’ discussions in
blogs, Internet sites, and Facebook pages (n = 2499). The findings indicate that
some parents who normally give their children routine vaccinations decided not
to give them OPV due to lack of faith in the health system, concerns about vaccine
safety and reasons specific to the polio outbreak in Israel. Some vaccinated
due to a misunderstanding, namely, they believed that OPV was supposed to
protect their children, when it was actually for overall societal well-being. This
study highlights the difficulty of framing the subject of vaccinations as a preventive
measure, especially when the prevention is for society at large and not to
protect the children themselves. The findings of this study are important because
they provide a glimpse into a situation that can recur in different places in the
world where a disease considered to have been ‘eradicated’ returns, and the public
is required to take measures which protect the public but which might put
individuals at risk. The conclusions from the analysis of the findings of this
study are that the public’s risk perception is based on a context-dependent
analysis, which the communicating body must understand and respect.
Background: Information about iodine intake is crucial for preventing thyroid diseases. Inadequate iodine intake can lead to thyroid diseases, including nontoxic nodular goiter (NNG). Objective: To estimate iodine intake and explore its correlation with thyroid diseases among Israeli adults living near the Mediterranean coast, where iodine-depleted desalinated water has become a major source of drinking water. Methods: Cross-sectional study of patients attending Barzilai Medical Center Ashkelon. Participants, who were classified as either NNG (n = 17), hypothyroidism (n = 14), or control (n = 31), provided serum thyroglobulin (Tg) and completed a semiquantitative iodine food frequency questionnaire. Results: Elevated serum Tg values (Tg > 60 ng/mL) were significantly more prevalent in the NNG group than in the other groups (29% versus 7% and 0% for hypothyroidism and controls, resp., P < 0.05). Mean estimated iodine intake was significantly lower in the NNG group (65 ± 30 µg/d) than in controls (115 ± 60 µg/d) (P < 0.05) with intermediate intake in the hypothyroid group (73 ± 38 µg/d). Conclusions: Elevated serum Tg values and low dietary iodine intake are associated with NNG among adult patients in Ashkelon District, Israel. Larger studies are needed in order to expand on these important initial findings.
Objectives. This study aimed to clarify the relationship between community water fluoridation (CWF) and IQ. Methods. We conducted a prospective study of a general population sample of those born in Dunedin, New Zealand, between April 1, 1972, and March 30, 1973 (95.4% retention of cohort after 38 years of prospective follow-up). Residence in a CWF area, use of fluoride dentifrice and intake of 0.5-milligram fluoride tablets were assessed in early life (prior to age 5 years); we assessed IQ repeatedly between ages 7 to 13 years and at age 38 years. Results. No significant differences in IQ because of fluoride exposure were noted. These findings held after adjusting for potential confounding variables, including sex, socioeconomic status, breastfeeding, and birth weight (as well as educational attainment for adult IQ outcomes). Conclusions. These findings do not support the assertion that fluoride in the context of CWF programs is neurotoxic. Associations between very high fluoride exposure and low IQ reported in previous studies may have been affected by confounding, particularly by urban or rural status. (Am J Public Health. Published online ahead of print May 15, 2014: e1-e5. doi:10.2105/AJPH.2013.301857).
The authors undertook a study to define the messages that exist in 2 communities of risk (e.g., high concentration of chemical facilities) using the principles of fantasy theme analysis and symbolic convergence theory. Through several methodological steps including a document review, interviews, focus groups, and a telephone survey (N = 450), the researchers determined the messages that dominate in the community, and were able to segment them into rhetorical visions based on master analogues. Analysis indicated that persons who adhere to different perspectives or opinions (measured as rhetorical visions) experience different amounts of uncertainty, control, and support or opposition for the industries that create the risks. This analysis adds depth to the risk communication literature and suggests that public relations practitioners can and should attempt to understand risk discourse content as well as the communication processes and risk perceptions held by key publics.
Most of the Republic of Ireland's public water supplies have been fluoridated since the mid-1960s while Northern Ireland has never been fluoridated, apart from some small short-lived schemes in east Ulster.
This study examines dental caries status in 16 year-olds in a part of Ireland straddling fluoridated and non-fluoridated water supply areas and compares two methods of assessing the effectiveness of water fluoridation. The cross-sectional survey tested differences in caries status by two methods: 1, Estimated Fluoridation Status as used previously in national and regional studies in the Republic and in the All-Island study of 2002; 2, Percentage Lifetime Exposure, a modification of a system described by Slade in 1995 and used in Australian caries research.
Adolescents were selected for the study by a two-part random sampling process. Firstly, schools were selected in each area by creating three tiers based on school size, and selecting schools randomly from each tier. Then random sampling of 16-year-olds from these schools, based on a pre-set sampling fraction for each tier of schools.
With both systems of measurement, significantly lower caries levels were found in those children with the greatest exposure to fluoridated water when compared to those with the least exposure.
The survey provides further evidence of the effectiveness in reducing dental caries experience up to 16 years of age. The extra intricacies involved in using the Percentage Lifetime Exposure method did not provide much more information when compared to the simpler Estimated Fluoridation Status method.
Thematic analysis is a poorly demarcated, rarely acknowledged, yet widely used qualitative analytic method within psychology. In this paper, we argue that it offers an accessible and theoretically flexible approach to analysing qualitative data. We outline what thematic analysis is, locating it in relation to other qualitative analytic methods that search for themes or patterns, and in relation to different epistemological and ontological positions. We then provide clear guidelines to those wanting to start thematic analysis, or conduct it in a more deliberate and rigorous way, and consider potential pitfalls in conducting thematic analysis. Finally, we outline the disadvantages and advantages of thematic analysis. We conclude by advocating thematic analysis as a useful and flexible method for qualitative research in and beyond psychology.
The systematic review has become widely recognised as an aid to evidence-based decision making in health care. Recently, there has been much interest around the value of systematic reviews in policy-making contexts. This article describes a relatively rare example of an explicit policy commitment to follow the findings of a systematic review, namely that of the efficacy and safety of the fluoridation of drinking water. We argue that although a policy-relevant systematic review may not be directly influential if its findings contradict prior beliefs and policy intent, it can be of value beyond the immediate policy response.
In this article, it is argued that uncertainty and risk are intermingled and that this has severe consequences for risk regulation. First, uncertainty and risk are considered in the context of the precautionary principle from a theoretical point of view. On the basis of an interdisciplinary reflection, it is concluded that a paradox can be observed. Subsequently it will be investigated how this so‐called uncertainty paradox works out in practice. This will be done by analysis of the Pfizer case, situated at the EU level. In this case, that related to the use of antibiotics as a growth promoter in the production of meat, the precautionary principle was used as policy and legal principle. The analysis will detail the regulatory complexities that result from the contradictions in precautionary thinking. In conclusion suggestions will be advanced for regulatory reform in the broader sense, including the role of experts, and an interdisciplinary research agenda will be proposed.
Background: Although fluoride may cause neurotoxicity in animal models and acute fluoride poisoning causes neurotoxicity in adults, very little is known of its effects on children’s neurodevelopment.
Objective: We performed a systematic review and meta-analysis of published studies to investigate the effects of increased fluoride exposure and delayed neurobehavioral development.
Methods: We searched the MEDLINE, EMBASE, Water Resources Abstracts, and TOXNET databases through 2011 for eligible studies. We also searched the China National Knowledge Infrastructure (CNKI) database, because many studies on fluoride neurotoxicity have been published in Chinese journals only. In total, we identified 27 eligible epidemiological studies with high and reference exposures, end points of IQ scores, or related cognitive function measures with means and variances for the two exposure groups. Using random-effects models, we estimated the standardized mean difference between exposed and reference groups across all studies. We conducted sensitivity analyses restricted to studies using the same outcome assessment and having drinking-water fluoride as the only exposure. We performed the Cochran test for heterogeneity between studies, Begg’s funnel plot, and Egger test to assess publication bias, and conducted meta-regressions to explore sources of variation in mean differences among the studies.
Results: The standardized weighted mean difference in IQ score between exposed and reference populations was –0.45 (95% confidence interval: –0.56, –0.35) using a random-effects model. Thus, children in high-fluoride areas had significantly lower IQ scores than those who lived in low-fluoride areas. Subgroup and sensitivity analyses also indicated inverse associations, although the substantial heterogeneity did not appear to decrease.
Conclusions: The results support the possibility of an adverse effect of high fluoride exposure on children’s neurodevelopment. Future research should include detailed individual-level information on prenatal exposure, neurobehavioral performance, and covariates for adjustment.
This paper introduces a theoretical framework that describes the importance of public's information sufficiency, risk perception, and self-efficacy as predictors of intended risk information seeking behaviour. Based on theoretical assumptions, measurement instruments for relevant concepts were developed and validated using data from a mail questionnaire. Relationships among selected determinants of risk information seeking behaviour were analysed. Results indicate that information needs, risk perception, and current knowledge are direct predictors of intentions to seek information. Trust, engagement, social influence, and self-efficacy affect risk perception and the need for information is influenced by engagement and social influence.
Water fluoridation is one of the most effective public health programs of the past century. However, efforts to extend water fluoridation into currently non-fluoridated areas are often thwarted. Despite considerable evidence regarding the effectiveness of water fluoridation at an individual level, published national community-based studies are rare. This study compared children's decay experience and prevalence between areas with and without water fluoridation in Australia.
Oral health data were obtained from clinical examinations of 128, 990 5- to 15-year-old children attending for a regular visit with their respective Australian state or territory School Dental Service in 2002. Water fluoridation status, residence remoteness, and socioeconomic status (SES) were obtained for each child's recorded residential postcode area.
Children from every age group had greater caries prevalence and more caries experience in areas with negligible fluoride concentrations in the water (<0.3 parts per million [ppm]) than in optimally fluoridated areas (> or = 0.7 ppm). Controlling for child age, residential location, and SES, deciduous and permanent caries experience was 28.7% and 31.6% higher, respectively, in low-fluoride areas compared with optimally fluoridated areas. The odds ratios for higher caries prevalence in areas with negligible fluoride compared with optimal fluoride were 1.34 (95% confidence interval [CI] 1.29, 1.39) and 1.24 (95% CI 1.21, 1.28) in the deciduous and permanent dentitions, respectively.
This study demonstrates the continued community effectiveness of water fluoridation and provides support for the extension of this important oral health intervention to populations currently without access to fluoridated water.
Recent attention on health-related information seeking has focused primarily on information seeking within specific health and health risk contexts. This study attempts to shift some of that focus to individual-level variables that may impact health risk information seeking across contexts. To locate these variables, the researcher posits an integrated model, the Planned Risk Information Seeking Model (PRISM). The model, which treats risk information seeking as a deliberate (planned) behavior, maps variables found in the Theory of Planned Behavior (TPB; Ajzen, 1991) and the Risk Information Seeking and Processing Model (RISP; Griffin, Dunwoody, & Neuwirth, 1999), and posits linkages among those variables. This effort is further informed by Kahlor's (2007) Augmented RISP, the Theory of Motivated Information Management (Afifi & Weiner, 2004), the Comprehensive Model of Information Seeking (Johnson & Meischke, 1993), the Health Information Acquisition Model (Freimuth, Stein, & Kean, 1989), and the Extended Parallel Processing Model (Witte, 1998). The resulting integrated model accounted for 59% of the variance in health risk information-seeking intent and performed better than the TPB or the RISP alone.
To review the safety and efficacy of fluoridation of drinking water.
Search of 25 electronic databases and world wide web. Relevant journals hand searched; further information requested from authors. Inclusion criteria were a predefined hierarchy of evidence and objectives. Study validity was assessed with checklists. Two reviewers independently screened sources, extracted data, and assessed validity.
Decayed, missing, and filled primary/permanent teeth. Proportion of children without caries. Measure of effect was the difference in change in prevalence of caries from baseline to final examination in fluoridated compared with control areas. For potential adverse effects, all outcomes reported were used.
214 studies were included. The quality of studies was low to moderate. Water fluoridation was associated with an increased proportion of children without caries and a reduction in the number of teeth affected by caries. The range (median) of mean differences in the proportion of children without caries was -5.0% to 64% (14.6%). The range (median) of mean change in decayed, missing, and filled primary/permanent teeth was 0.5 to 4.4 (2.25) teeth. A dose-dependent increase in dental fluorosis was found. At a fluoride level of 1 ppm an estimated 12.5% (95% confidence interval 7.0% to 21.5%) of exposed people would have fluorosis that they would find aesthetically concerning.
The evidence of a beneficial reduction in caries should be considered together with the increased prevalence of dental fluorosis. There was no clear evidence of other potential adverse effects.
Adding fluoride to water supplies to prevent dental caries is controversial. K K Cheng, Iain Chalmers, and Trevor A Sheldon identify the issues it raises in the hope of furthering constructive public consultation and debate
Water fluoridation is one of the most effective public health programs of the past century. However, efforts to extend water fluoridation into currently non-fluoridated areas are often thwarted. Despite considerable evidence regarding the effectiveness of water fluoridation at an individual level, published national community-based studies are rare. This study compared children's decay experience and prevalence between areas with and without water fluoridation in Australia.
After collecting qualitative data from in-depth interviews, focus groups, or field observations, students and researchers often struggle to make sense of it. This step-by-step guide draws on the authors' many years of experience carrying out qualitative research and conducting trainings on the subject. Their book describes how to analyze qualitative data in a systematic and rigorous way. The authors introduce and outline applied thematic analysis, an inductive approach that draws on established and innovative theme-based techniques suited to the applied research context. Chapters follow the sequence of activities in the analysis process and also include discussions of mixed methods, choosing the most appropriate software, and how to write up and present the results.
"This book presents what all of the books I've tried to use in the past have failed to present—how to analyze qualitative data."—Catherine C. Schifter, Temple University
"This book does a wonderful job of explaining how important thematic analysis is for producing good research, and it uses rich and detailed examples to do it."—Matthew Hartley, University of Pennsylvania
Authorities often refrain from communicating risks out of fear to arouse negative feelings amongst the public and to create negative reactions in terms of the public’s behavior. This study examines the impact of communicating risks on the public’s feelings and behavioral intentions regarding an uncontrollable risk related to fresh produce. In addition, the impact of risk communication is compared between a situation in which the risk either does or does not develop into a crisis, by means of a 2 (risk communication vs. no risk communication) × 2 (crisis communication vs. no crisis communication) between-subjects factorial design. The results show that communicating risks has a positive impact on the behavioral intention to keep on eating fresh produce compared to when no risk communication was provided, as it reduces negative feelings amongst the public. In addition, the findings illustrate that when a risk develops into an actual crisis, prior risk communication can result in greater trust in the government and reduce perceived government responsibility for the crisis when the crisis hits. Based on these findings, it can be suggested that risk communication is an effective tool for authorities in preparing the public for potential crises. The findings indicate that communicating risks does not raise negative reactions amongst the public, on the contrary, and that it results in more positive perceptions of the authorities.
Objective: To review the safety and efficacy of fluoridation of drinking water.
Design: Search of 25 electronic databases and world wide web. Relevant journals hand searched; further information requested from authors. Inclusion criteria were a predefined hierarchy of evidence and objectives. Study validity was assessed with checklists. Two reviewers independently screened sources, extracted data, and assessed validity.
Main outcome measures: Decayed, missing, and filled primary/permanent teeth. Proportion of children without caries. Measure of effect was the difference in change in prevalence of caries from baseline to final examination in fluoridated compared with control areas. For potential adverse effects, all outcomes reported were used.
Results: 214 studies were included. The quality of studies was low to moderate. Water fluoridation was associated with an increased proportion of children without caries and a reduction in the number of teeth affected by caries. The range (median) of mean differences in the proportion of children without caries was −5.0% to 64% (14.6%). The range (median) of mean change in decayed, missing, and filled primary/permanent teeth was 0.5 to 4.4 (2.25) teeth. A dose-dependent increase in dental fluorosis was found. At a fluoride level of 1 ppm an estimated 12.5% (95% confidence interval 7.0% to 21.5%) of exposed people would have fluorosis that they would find aesthetically concerning.
Conclusions: The evidence of a beneficial reduction in caries should be considered together with the increased prevalence of dental fluorosis. There was no clear evidence of other potential adverse effects.
While previous research has suggested that there is an association between fluoride ingestion and the incidence of hypothyroidism, few population level studies have been undertaken. In England, approximately 10% of the population live in areas with community fluoridation schemes and hypothyroidism prevalence can be assessed from general practice data. This observational study examines the association between levels of fluoride in water supplies with practice level hypothyroidism prevalence.
We used a cross-sectional study design using secondary data to develop binary logistic regression models of predictive factors for hypothyroidism prevalence at practice level using 2012 data on fluoride levels in drinking water, 2012/2013 Quality and Outcomes Framework (QOF) diagnosed hypothyroidism prevalence data, 2013 General Practitioner registered patient numbers and 2012 practice level Index of Multiple Deprivation scores.
We found that higher levels of fluoride in drinking water provide a useful contribution for predicting prevalence of hypothyroidism. We found that practices located in the West Midlands (a wholly fluoridated area) are nearly twice as likely to report high hypothyroidism prevalence in comparison to Greater Manchester (non-fluoridated area).
In many areas of the world, hypothyroidism is a major health concern and in addition to other factors-such as iodine deficiency-fluoride exposure should be considered as a contributing factor. The findings of the study raise particular concerns about the validity of community fluoridation as a safe public health measure.
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Scientific controversies are associated with significant uncertainty. Despite this uncertainty, available knowledge must be communicated to the public, who are potentially at risk. There are contradictions in the existing literature about the value of communicating uncertainty associated with science. Some scientists and decision-makers believe that communicating uncertainty to the public will produce panic and confusion, and will discredit science. Others believe that uncertainty must be communicated to increase trust in science. We tested reactions to communication about uncertainty related to the controversial link between exposure to endocrine disrupters and a decline in human male fertility. Our empirical setup used focus groups and qualitative analysis of participants’ perceived uncertainty and their emotions. The results show that laypeople raise more and different uncertainties than those communicated by researchers. Moreover, laypeople did not react to uncertainty ‘globally;’ they had different reactions to the different sources of uncertainty. Uncertainty did not elicit panic in this case study. Rather, uncertainty was reassuring, except when it was associated with an inability to precisely identify and, therefore, control the cause of male reproductive disorders. We discuss the emotions expressed and their relationships with communication about scientific uncertainty (powerlessness, guilt, outrage, etc.). We also note that feelings of confusion increase after uncertainty has been communicated.
Neurodevelopmental disabilities, including autism, attention-deficit hyperactivity disorder, dyslexia, and other cognitive impairments, affect millions of children worldwide, and some diagnoses seem to be increasing in frequency. Industrial chemicals that injure the developing brain are among the known causes for this rise in prevalence. In 2006, we did a systematic review and identified five industrial chemicals as developmental neurotoxicants: lead, methylmercury, polychlorinated biphenyls, arsenic, and toluene. Since 2006, epidemiological studies have documented six additional developmental neurotoxicants-manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene, and the polybrominated diphenyl ethers. We postulate that even more neurotoxicants remain undiscovered. To control the pandemic of developmental neurotoxicity, we propose a global prevention strategy. Untested chemicals should not be presumed to be safe to brain development, and chemicals in existing use and all new chemicals must therefore be tested for developmental neurotoxicity. To coordinate these efforts and to accelerate translation of science into prevention, we propose the urgent formation of a new international clearinghouse.
Controversy persists concerning the impact of community water fluoridation on bone health in adults, and few studies have assessed relationships with bone at younger ages. Ecological studies of fluoride's effects showed some increase in bone mineral density of adolescents and young adults in areas with fluoridated water compared with non-fluoridated areas. However, none had individual fluoride exposure measures. To avoid ecological fallacy and reduce bias, we assessed associations of average daily fluoride intake from birth to age 15 yr for Iowa Bone Development Study cohort members with age 15 yr dual-energy x-ray absorptiometry (DXA) bone outcomes (whole body, lumbar spine, and hip), controlling for known determinants (including daily calcium intake, average daily time spent in moderate-to-vigorous intensity physical activity, and physical maturity). Mean (SD) daily fluoride intake was 0.66 mg (0.24) for females and 0.78 mg (0.30) for males. We found no significant relationships between daily fluoride intake and adolescents' bone measures in adjusted models (for 183 females, all p values ≥ .10 and all partial R(2) ≤ 0.02; for 175 males, all p values ≥ .34 and all partial R(2) ≤ 0.01). The findings suggest that fluoride exposures at the typical levels for most US adolescents in fluoridated areas do not have significant effects on bone mineral measures.
The aim of this study was to evaluate the systemic effect of water fluoridation on dental caries prevalence and experience in Cheongju, South Korea, where water fluoridation ceased 7 years previously.
A cross-sectional survey was employed at two schools where water fluoridation had ceased (WF-ceased area) and at two schools where the water had never been fluoridated (non-WF area). The schools in the non-WF area were of a similar population size to the schools in the WF-ceased area. Children of three age groups were examined in both areas: aged 6 (n = 505), 8 (n = 513), and 11 years (n = 467). The differences in the mean number of decayed or filled primary teeth (dft) and the mean number of decayed, missing, or filled permanent teeth (DMFT) scores between areas after adjusting for oral health behaviors and socio-demographic factors were analyzed by a Poisson regression model.
The regression model showed that the DMFT ratio for children aged 11 years in the WF-ceased area was 0.581 (95% CI 0.450-0.751). In contrast, the dft ratio for age 6 in the WF-ceased area was 1.158 (95% CI 1.004-1.335). Only the DMFT ratio for age 8 (0.924, 95% CI 0.625-1.368) was not significant.
While 6-year-old children who had not ingested fluoridated water showed higher dft in the WF-ceased area than in the non-WF area, 11-year-old children in the WF-ceased area who had ingested fluoridated water for approximately 4 years after birth showed significantly lower DMFT than those in the non-WF area. This suggests that the systemic effect of fluoride intake through water fluoridation could be important for the prevention of dental caries.
Images of group panic and collective chaos are ubiquitous in Hollywood movies, mainstream media and the rhetoric of politicians. But, contrary to these popular portrayals, group panic is relatively rare. In disasters people are often models of civility and cooperation.
Over the past number of years the reporting of food scares, particularly in European context, have grown in prevalence. These scares are more often than not amplified by the media leading to greater pressure on regulators, industry and other stakeholders to communicate the actual risks associated with the food issue in question accurately. The aims of this paper is three fold: firstly, provide a brief background on the history of risk communication itself. Secondly, to summarise some of the main theoretical avenues that are presently favoured by the wider academic (risk) community. The final section of the paper provides research ideas regarding what academics working in the food risk communication area may wish to look at now. Among the issues highlighted include addressing the issue of media amplification, rebuilding public trust, and better communicating uncertainty.
The author considers the implications for current assumptions about scientific knowledge and environmental policy raised by the preventive approach and the associated Precautionary Principle. He offers a critical examination of approaches to characterizing different kinds of uncertainty in policy knowledge, especially in relation to decision making upstream from environmental effects. Via the key dimension of unrecognized indeterminacy in scientific knowledge, the author argues that shifting the normative principles applied to policy use of science is not merely an external shift in relation to the same body of 'natural' knowledge, but also involves the possible reshaping of the 'natural' knowledge itself.
"This book provides step-by-step instructions on how to analyze text generated from in-depth interviews and focus groups - i.e., transcripts. The book is primarily designed for research studies with an applied focus, but is also useful for theoretically oriented qualitative research. The book covers all aspects of the qualitative data analysis process including planning, data preparation, identification of themes, codebook development and code application, reliability and inter-coder agreement, data reduction techniques, comparative techniques, integration with quantitative data, and software considerations. The book describes what the authors call "applied thematic analysis", because it is the approach predominantly used in applied qualitative studies (and increasingly in academic contexts). The method employs a phenomenological approach to data analysis which has a primary aim of describing the experiences and perceptions of research participants. The approach presented is similar to Grounded Theory - in that it is inductive, content-driven, and searches for themes within textual data - and is complementary to Grounded Theory on many levels. However, within an applied context a phenomenological approach is primarily concerned with characterizing and summarizing perceptions and lived experiences and applying the results to a particular research problem, rather than building and assessing theoretical models"--
Dealing with uncertain risks is an important challenge. Uncertain risks need to be sharply distinguished from traditional, simple risks which can be calculated by means of statistics. Arguably current governance of uncertain risks tends to erode into organized irresponsibility, i.e., society's ill‐preparedness and inability to deal with surprises, negative consequences and/or long‐term impacts which are associated with uncertain risks, notwithstanding all institutions and procedures in place. In such cases, a particular pattern in risk regulation can be identified, the uncertainty paradox, which is an umbrella term for situations in which uncertainty is acknowledged, but the role of science is framed as one of providing certainty. This article highlights the need to further understand the uncertainty paradox by investigating actual decision‐making processes. Through case‐study research on EU GMO regulation this article examines how various actors actually deal with science, knowledge and uncertainty. Four mechanisms sustaining the uncertainty paradox are inferred: 1) uncertainty intolerance; 2) boundary work; 3) the inclination to equate uncertainty with risk; and 4) technocratic provisions. In conclusion, some suggestions are advanced as to how to break through the uncertainty paradox.
Proposes a descriptive model of how people make judgments under ambiguity that assumes an anchoring-and-adjustment process in which an initial estimate provides the anchor, and adjustments are made for what might be. The latter is modeled as the result of a mental simulation process that reflects not only the amount of ambiguity, which affects the size of the simulation but also one's attitude toward ambiguity, which affects the differential weighting of imagined probabilities. A 2-parameter model of this process is shown to be consistent with D. Ellsberg's (1961) original paradox, the nonadditivity of complementary probabilities, current psychological theories of risk, and J. M. Keynes's (1921) idea of the "weight of evidence." Four experiments were conducted to test the model. In Exps I and II, each with 32 volunteers, the model accurately predicted inferential judgments; in Exp III, with 20 Ss, the model predicted choices between gambles; and in Exp IV, with 112 masters of business students, it showed how buying and selling prices for insurance are influenced by one's attitude toward ambiguity. Results are discussed with respect to the importance of ambiguity in assessing uncertainty, the use of cognitive strategies in judgments under ambiguity, the role of ambiguity in risky choice, and extensions of the model. Further explanations of specific facets of the model are appended. (62 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
One of the main themes that has emerged from behavioral decision research during the past 2 decades is the view that people's preferences are often constructed in the process of elicitation. This concept is derived in part from studies demonstrating that normatively equivalent methods of elicitation often give rise to systematically different responses. These "preference reversals" violate the principle of procedure invariance that is fundamental to theories of rational choice and raise difficult questions about the nature of human values. If different elicitation procedures produce different orderings of options, how can preferences be defined and in what sense do they exist? Describing and explaining such failures of invariance will require choice models of far greater complexity than the traditional models. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Salt iodization has been introduced in many countries to control iodine deficiency. The two most commonly used approaches to assessing iodine nutrition on the population level are estimation of the household penetration of adequately iodized salt (HHIS) and measurement of urinary iodine concentrations (UICs). The aim of this review is to assess global and regional iodine status in 2012 by using each of these indicators.
The most recent national data on HHIS were obtained from UNICEF. The most recent data on UICs, primarily national data in school-age children, were obtained from a systematic literature search, the International Council for the Control of Iodine Deficiency Disorders and the WHO Micronutrients Database. The median UIC was used to classify national iodine status and the UIC distribution to estimate the number of individuals with low iodine intakes. Thirty-two countries are iodine deficient based on the national median UIC. Globally, 29.8% of school-age children (246 million) are estimated to have insufficient iodine intake. Out of 128 countries with HHIS data, 37 countries have salt iodization coverage that meets the international goal of at least 90% of households consuming adequately iodized salt and 39 countries have coverage rates of less than 50%. Overall, ≈70% of households worldwide have access to iodized salt.
Iodized salt programs need to be strengthened and extended to reach nearly one-third of the global population that still has inadequate iodine intakes.
Risk perception is sometimes measured by means of judgments about worry, sometimes as perceived risk more directly. However, perceived level of risk calls for a more intellectual judgment and worry tends to refer to emotional reactions. These two are therefore not the same and need not be strongly correlated. Results reported here show that perceived risk and worry are indeed weakly correlated, both for generalized worry and for more specific measures of worry matched with the same hazard as risk ratings. A distinction is suggested between cognitive, abstract hazards and concrete, sensory hazards, with implications for the worry-perceived risk relationship. It was furthermore found by means of cluster analysis that there were groups of subject displaying different dynamics of risk and worry.
Scientific experts (drawn from scientific institutions, universities, industry, and government) were interviewed about how they thought the general public might handle information about uncertainty associated with risk analysis. It was found that, for many people within the scientific community, there was a widespread belief that the general public were unable to conceptualize uncertainties associated with risk management processes. Many scientists thought that providing the public with information about uncertainty would increase distrust in science and scientific institutions, as well as cause panic and confusion regarding the extent and impact of a particular hazard. It was concluded that scientists still appear to be subscribing to the deficit model of science communication, and it is vital that effective mechanisms for communicating about risk uncertainty with the public must be developed as a matter of urgency, particularly as increased transparency in risk management processes means that scientific uncertainties associated with risk analysis become more likely to be the subject of public scrutiny and debate.
The "optimal" intake of fluoride has been widely accepted for decades as between 0.05 and 0.07 mg fluoride per kilogram of body weight (mg F/kg bw) but is based on limited scientific evidence. The purpose of this paper is to present longitudinal fluoride intake data for children free of dental fluorosis in the early-erupting permanent dentition and free of dental caries in both the primary and early-erupting permanent teeth as an estimate of optimal fluoride intake.
Data on fluoride ingestion were obtained from parents of 602 Iowa Fluoride Study children through periodic questionnaires at the ages of 6 weeks; 3, 6, 9, 12, 16, 20, 24, 28, 32, and 36 months; and then at 6-month intervals thereafter. Estimates of total fluoride intake at each time point were made by summing amounts from water, dentifrice, and supplements, as well as other foods and beverages made with, or containing, water. Caries data were obtained from examinations of children at ages 5 and 9 years, whereas fluorosis data were obtained from examinations of children only at age 9 years.
The estimated mean daily fluoride intake for those children with no caries history and no fluorosis at age 9 years was at, or below, 0.05 mg F/kg bw for nearly all time points through the first 48 months of life, and this level declined thereafter. Children with caries had generally slightly less intakes, whereas those with fluorosis generally had slightly higher intakes.
Given the overlap among caries/fluorosis groups in mean fluoride intake and extreme variability in individual fluoride intakes, firmly recommending an "optimal" fluoride intake is problematic.
We articulate a model that focuses on characteristics of individuals that might predispose them to seek and process information about health in different ways. Specifically, the model proposes that seven factors-(1) individual characteristics, (2) perceived hazard characteristics, (3) affective response to the risk, (4) felt social pressures to possess relevant information, (5) information sufficiency, (6) one's personal capacity to learn, (7) beliefs about the usefulness of information in various channels-will influence the extent to which a person will seek out this risk information in both routine and nonroutine channels and the extent to which he or she will spend time and effort analyzing the risk information critically. By adapting and synthesizing aspects of Eagly and Chaiken's Heuristic-Systematic Model and Ajzen's Theory of Planned Behavior, we also expect that people who engage in more effortful information seeking and processing are more likely to develop risk-related cognitions, attitudes, and behaviors that are more stable (i.e., less changeable or volatile) over time. Since most forms of health information campaigns attempt to get people to adopt habitual or lifestyle changes, factors leading to the stability or volatility of those behavioral changes are essential concerns.
Water fluoridation in Israel was initially introduced on a municipal level in 1981. Legislation in favor of national water fluoridation was approved in 1998. Over the last year an increasing campaign against the fluoridation project has become more and more evident. The material published by the opponents to fluoridation, distributed in pamphlets, daily journals and mass media resources, illustrate as in the USA, an endless and unrestrained "duel" between opponents and supporters of fluoridation. In Israel, in contrast to the USA, referenda are unprecedented, therefore, the political "battle field" is transferred to the municipal authorities and the Knesset. The pivotal component of the Israeli opponents to fluoridation regards the public's health and safety. Unscientific publications appear regularly in the daily journals and electronic mass media with no reference of supporting studies ever mentioned. The inevitable question addressed in this article is what are the best ways of action to be taken by the supporters of fluoridation is Israel. The main and most important mode of action against this campaign is, undoubtedly, continuous persuasion. Nevertheless, the continuous daily struggle of the supporters must be in a world-wide frame and be adjusted to the different target groups of the public. An effective confrontation should include nation-wide available publications (internet, daily papers and multimedia) with special emphasis on the important subjects (e.g. evidence based care, significance of toxic doses and the value of social justice), in a format comprehensible to the public and its leaders. The American experience helps us to understand that the opposition to water fluoridation will not diminished but, on the contrary, is expected to strengthen. We must look forward with no illusions and establish ways of action and cooperation by learning from past experience and from that of our collaborators. This will serve as the basis for the ongoing frank and persuasive efforts, derived from a deep and honest belief in the justice of our way.
This article explores the use of the precautionary principle in situations of intermingled uncertainty and risk. It analyses how the so-called uncertainty paradox works out by examining the Pfizer case. It reveals regulatory complexities that result from contradictions in precautionary thinking. In conclusion, a plea is made for embedment of uncertainty information, while stressing the need to rethink regulatory reform in the broader sense.
December TIM Poll: Goggle Continue to Lead
Avraham, D. 2013. "December TIM Poll: Goggle Continue to Lead." Walla, January 14 [July
24, 2015]. http://b.walla.co.il/item/2606671
Petition against Health Minister's Decision to Stop Water Fluoridation in Israel Submitted to the Supreme Court
DoctorsOnly Desk. 2014. "Petition against Health Minister's Decision to Stop Water Fluoridation in Israel Submitted to the Supreme Court." DoctorsOnly, October 7 July 24, 2015.
Litzmann Reverses German's Decision and Restores Fluoride to Drinking Water
Efrati, I., and Z. Rinat. 2015. "Litzmann Reverses German's Decision and Restores Fluoride
to Drinking Water." Haaertz, May 31 [July 24, 2015].
The Role of Uncertainty Intolerance in European Risk Governance
Fox, T. 2009. "The Role of Uncertainty Intolerance in European Risk Governance." Paper
read at Risk Research Symposium, King's College London, London.