Risk Reduction Effect Research Articles

Effects of Risk Representation and Scope on Willingness to Pay for Reduced Risks: Evidence from Tokyo Bay, Japan

When applying the contingent valuation method (CVM) in risk reduction studies, some studies report that willingness to pay (WTP) is insensitive to the magnitude of risk reduction while other studies do not. On the other hand, social-psychological research has shown that the affect heuristic biases judgments on probability, relative frequency, and risk. This article examines both magnitude (or scope) effect and affect heuristic (or representation) effect on WTP for risk reduction measures against tsunamis by introducing two experimental (i.e., absolute and relative) systems with four different representations to evaluate public behaviors in two different scenarios of risk reduction. Two common denominators (100 and 10,000) are introduced into absolute risk reduction representation (i.e., "of every 100 persons, from present 2 deaths to 1") to form different formats (i.e., "of every 10,000 persons from 200 to 100," and "of every 100,000 persons from 2,000 deaths to 1,000"). There is little evidence that WTP estimates are sufficiently sensitive to the magnitude of risk reduction, but relative risk reduction representations may be better than the absolute one given in CVM mail surveys when the risk is small. There is a statistically insignificant effect of risk reduction representations on respondent frequency, but mixed effects on the monetary values of WTP at the level of 0.05. The representation effect of absolute risk reduction on the WTP value varies with the common denominator. The larger the common denominator, the less the WTP to reduce the risk of tsunamis, and the significance probability is improved to less than the level of 0.05 when the common denominator becomes large enough. The findings suggest that improved methods are required for estimating the rates of tradeoff between fatality risk and other goods among consumers.

Toward Healthy Aging: The Preservation of Health

Chronic disease has emerged in recent decades as the major cluster of health concerns of the American population. Increasing evidence indicates that, in most instances, these diseases have been present for long periods of time before becoming clinically manifest. In some instances, it is clear that they may begin in childhood and reach clinical expression only decades later. Furthermore, relevant risk factors for a number of these diseases have been identified and the beneficial effects of risk reduction defined. These disease characteristics translate into lengthy opportunities to identify, mitigate, or prevent serious chronic disorders. A useful framework invokes the health quantum, the "dose" of good health with which the individual is born and that is subjected to erosive forces at each stage of life from conception to old age. A coherent orientation toward the preservation of health across the lifespan is proposed, involving coordinated efforts by the individual, the clinical and public health communities, and the policy enterprise.

Association study of variants in two ion-channel genes (TSC and CLCNKB) and hypertension in two ethnic groups in Northwest China

Background Abnormalities in renal sodium and water retention and membrane ion transport play important roles in development of hypertension. Recently, Arg904Gln variant of thiazide-sensitive NaCl-cotransporter gene (TSC) and Thr418Ser variant of renal epithelial Cl-channel ClC-Kb gene (CLCNKB) were found implicated in the prevalence of essential hypertension (EH). The objective of this study was to examine the role of these two variants on EH in two Chinese minorities—Kazaks and Uyghurs. Methods A case–control study was conducted in Kazak herdsmen and Uyghur farmers live in Xinjiang Uyghur Autonomous Region of Northwest China. Results For the Arg904Gln polymorphism in the TSC gene, we observed a stronger trend of 904Gln allele in controls than hypertensives in Uyghurs ( p = 0.058), but the greater prevalence of genotype of 904Gln carrier reached significance ( p = 0.015). No association or trend with hypertension was observed at Arg904Gln in Kazaks. For the Thr418Ser variant of the CLCNKB gene in Kazaks, we observed a significantly higher prevalence of 418Ser allele frequencies in hypertensives than controls ( p = 0.037), but the higher prevalence of genotype of 418Ser carrier did not reach significance ( p = 0.08).No association with hypertension was observed at Thr418Ser in Uyghurs. Conclusion The risk reduction effect of 904Gln to hypertension in Uyghurs and the association of 418Ser to hypertension in Kazaks are weak. Given that we have explored two polymorphisms in each of two populations, for a total of four independent tests, a Bonferroni correction for multiple tests (0.05/4) renders non-significant of our results in our two Chinese populations ( α = 0.0125). The roles of Thr418Ser polymorphism of the CLCNKB gene and Arg904Gln polymorphism in the TSC gene on essential hypertension need to be explored in other ethnic groups.

Primary Prevention of Cardiovascular Disease in Nursing Practice: Focus on Children and Youth

Cardiovascular disease (CVD) is a leading cause of morbidity and premature mortality in women and men in the United States, most of the industrialized world, and many developing countries.1 Data accumulated over the past 3 decades indicate that atherosclerotic-CVD processes begin early in childhood and are influenced over the life course by genetic and potentially modifiable risk factors and environmental exposures. Taken together, these data provide compelling evidence for primary prevention of CVD beginning early in childhood. Within the pediatric healthcare community, this evidence has prompted and informed the development of science-based guidelines with recommendations for individual/high-risk and population-based approaches to primary prevention of CVD in children and youth. The purpose of this statement is to provide an overview of the evidence and current science-based recommendations and to emphasize the role of advanced practice nurses in the implementation of strategies consistent with population-based and individual/high-risk approaches to CVD prevention in children and youth. Evidence-based guidelines for primary and secondary prevention of CVD in adults are informed by the results of randomized controlled trials. The existing evidence (discussed below) argues convincingly for prevention of CVD beginning early in childhood. It is noteworthy that data from randomized controlled trials documenting the effect of risk reduction in childhood on the development of CVD in adulthood are nonexistent. Similarly, no long-term longitudinal studies have been conducted to determine the absolute levels of risk factors measured in childhood that predict CVD in adult life. However, evidence from laboratory, clinical, and epidemiological studies supports the need for primary prevention of CVD beginning early in life and has prompted and informed existing guidelines for children and adolescents. ### Laboratory/Pathology and In Vivo/Clinical Studies Autopsy studies conducted as part of the Bogalusa Heart Study2,3 and the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Study4,5 demonstrate significant positive associations between potentially modifiable …

Cardiovascular Risk Reduction in High-Risk Pediatric Patients*

Although for most children the process of atherosclerosis is subclinical, dramatically accelerated atherosclerosis occurs in some pediatric disease states, with clinical coronary events occurring in childhood and very early adult life. As with most scientific statements about children and the future risk for cardiovascular disease, there are no randomized trials documenting the effects of risk reduction on hard clinical outcomes. A growing body of literature, however, identifies the importance of premature cardiovascular disease in the course of certain pediatric diagnoses and addresses the response to risk factor reduction. For this scientific statement, a panel of experts reviewed what is known about very premature cardiovascular disease in 8 high-risk pediatric diagnoses and, from the science base, developed practical recommendations for management of cardiovascular risk.

Supply Response under Risk: Implications for Counter-Cyclical Payments' Production Impact

This study investigates the role of risk in farmers' acreage decisions for major field crops in the North Central region by revisiting an earlier study by Chavas and Holt. The empirical model is forward-looking and reflects better variable measurement. We test the effects of wealth and revenue risk on supply response. Estimated results are also used to examine the production impact of counter-cyclical payments (CCPs). We find that the effects of risk on supply response are not strong. An increase in initial wealth would lead to greater crop acreage, consistent with decreasing absolute risk aversion. The effect of CCPs on production appears to be negligible. T he 2002 Farm Act offers producers income support and revenue risk reduction through counter-cyclical payments (CCPs). These payments are made available to producers of covered commodities whenever the effective price--the sum of the direct payment rate and the national average farm price or loan rate (whichever is higher)-is less than the target price.' CCPs received by producers do not depend on current commodity production, but on historical base acreage and payment yields. CCPs protect producers from down-side price risk and so might have an impact on their production decisions. The potential for CCPs to cause production and trade distortions due to wealth and risk reduction effects has been noted in the ongoing agricultural trade policy debate. A seminal study by Chavas and Holt has been cited as the primary evidence of potential production and trade distortions caused by decoupled payments (such as direct payments) and partially decoupled payments (such as CCPs). The Chavas and Holt study shows that wealth and price risk have statistically significant effects on U.S. corn and soybean acreage decisions, but the impacts are small. However, the study is outdated because data used in the empirical model extend only through the mid 1980s. Since then, the policy environment has evolved away from supply controls and toward greater planting flexibility.

The effect of a community-based coronary risk reduction: The Rockford CHIP

Objective. The aim of this study was to assess the clinical effects of a community-based lifestyle intervention program in reducing coronary risk, especially in a high risk group. Method. The 40-hour educational curriculum of the Coronary Health Improvement Project (CHIP) delivered over a 30-day period with clinical and nutritional assessments before and after was offered in the spring and fall of 2000 to 2002 through the Center for Complementary Medicine of the SwedishAmerican Health System in Rockford, Illinois to its employees and the general public. The participants were instructed to optimize their diet, quit smoking and exercise daily (walking 30 min/day). Results. The data of the 5 CHIP programs were pooled and analyzed. 544 men and 973 women (almost all Caucasian; mean age 55 years) were eligible for analysis. At the end of the 30-day intervention period, stratified analyses of total cholesterol, LDL, triglycerides, blood glucose, blood pressure and weight showed highly significant reductions with the greatest improvements among those at highest risk. Conclusion. Well-designed community-based intervention programs can improve lifestyle choices and health habits. They can also markedly and rather quickly reduce the level of coronary risk factors in a non-randomized population.

Primary prevention of cardiovascular disease: Cost-effectiveness comparison

The aim of this study was to evaluate the cost-effectiveness of four risk-lowering interventions (smoking cessation, antihypertensives, aspirin, and statins) in primary prevention of cardiovascular disease. Using data from the Framingham Heart Study and the Framingham Offspring study, we built life tables to model the benefits of the selected interventions. Participants were classified by age and level of risk of coronary heart disease. The effects of risk reduction are obtained as numbers of death averted and life-years saved within a 10-year period. Estimates of risk reduction by the interventions were obtained from meta-analyses and costs from Dutch sources. The most cost-effective is smoking cessation therapy, representing savings in all situations. Aspirin is the second most cost-effective (euro 2,263 to euro 16,949 per year of life saved) followed by antihypertensives. Statins are the least cost-effective (euro 73,971 to euro 190,276 per year of life saved). A cost-effective strategy should offer smoking cessation for smokers and aspirin for moderate and high levels of risk among men 45 years of age and older. Statin therapy is the most expensive option in primary prevention at levels of 10-year coronary heart disease risk below 30 percent and should not constitute the first choice of treatment in these populations.

Cardiovascular Risk Reduction in High-Risk Pediatric Patients

Although for most children the process of atherosclerosis is subclinical, dramatically accelerated atherosclerosis occurs in some pediatric disease states, with clinical coronary events occurring in childhood and very early adult life. As with most scientific statements about children and the future risk for cardiovascular disease, there are no randomized trials documenting the effects of risk reduction on hard clinical outcomes. A growing body of literature, however, identifies the importance of premature cardiovascular disease in the course of certain pediatric diagnoses and addresses the response to risk factor reduction. For this scientific statement, a panel of experts reviewed what is known about very premature cardiovascular disease in 8 high-risk pediatric diagnoses and, from the science base, developed practical recommendations for management of cardiovascular risk.

Reducing HIV Transmission Risk by Increasing Serostatus Disclosure: A Mathematical Modeling Analysis

Persons living with HIV infection are encouraged to disclose their HIV-positive serostatus to prospective sex partners to decrease the likelihood of unsafe sex and HIV transmission. However, the effectiveness of serostatus disclosure as a preventive measure is not known. We developed a mathematical framework for assessing the HIV transmission risk reduction effectiveness of serostatus disclosure, examined how increasing the disclosure rate affects the transmission risk reduction effectiveness of disclosure, and explored the interaction between condom use and disclosure effectiveness. Under base-case assumptions, serostatus disclosure reduced the risk of HIV transmission by between 17.9% and 40.6% relative to no disclosure. Increasing the disclosure rate from the base-case value of 51.9-75.7% produced a 26.2-59.2% reduction in risk. The findings of this modeling study strongly support intervention efforts to increase both serostatus disclosure and condom use by persons living with HIV.

Credit spread volatility, bond ratings and the risk reduction effect of watchlistings

AbstractThis article examines the relationship between the volatility of the credit risk premium of a plain vanilla bond and its credit rating. We calculate volatilities over different time windows and test for differences in the mean volatility depending on the bond rating. We check for the influence of further factors that are theoretically relevant for the explanation of the credit spread volatility. Moreover, we check the dynamic effect of rating changes on bond spread volatility. Finally, we test whether credit watchlistings influence credit spread volatility. We confirm prior studies in that, generally, credit ratings rank the risk of bonds according to credit spread volatility. We further find that rating changes have a dynamic influence on spread volatilities. Additionally it is shown that credit watchlistings significantly reduce the volatility. Thus, watchlistings are perceived to offer valuable information. Copyright © 2006 John Wiley & Sons, Ltd.

Sib-size, birth order and risk of overweight in junior high school students in Japan: Results of the Toyama Birth Cohort Study

Objective. To investigate whether there is a relationship between sib-size, birth order and the risk of overweight in junior high school students. Method. Sib-size, birth order, height and weight of subjects and their parents, and other lifestyle factors were obtained through a questionnaire survey conducted between June and July 2002 from 7,959 junior high students in Toyama prefecture, Japan. Logistic regression analysis was performed to examine the associations. Boys and girls were analyzed separately. Results. Boys from three-child families showed a significantly lower risk of overweight than only boys (odds ratio (OR) = 0.66, p = 0.010), and girls from larger families have a significantly lower risk than only girls ( p for trend = 0.001). Compared to middle-born girls, only girls have a significantly higher risk of overweight (OR = 2.22, p < 0.001). The risk of overweight in boys was significantly lower with increasing number of elder sibling or sister. However, increasing of any one sibling almost had the same risk reduction effect on the risk of overweight in girls (OR ranged from 0.74 to 0.76, p <= 0.001). Conclusion. Children without siblings are the ones most at risk for overweight, especially in girls. Birth order and sib-size are possible risk factors for the development of overweight and obesity.

Does global diversification destroy firm value?

Previous empirical studies have found that global diversification results in 18% shareholder loss. In this paper, we examine the sources behind the global diversification shareholder value loss in a contingent claims framework. This postulates that the risk-reduction effects of global diversification should decrease the value of shareholder equity (call option), whereas they should increase bondholder value. Consequently, near-all equity globally diversified firms should not experience a shareholder value loss. Consistent with the riskreduction effects of global diversification, using cross-border acquisitions data we find three major results. First, shareholder value loss to global diversification is directly related to firms’ leverage. Second, near-all equity firms do not trade at a discount. Third, the use of book value debt in estimating excess value produces a downward bias in globally diversified firms. Our findings confirm that increased foreign involvement increases bondholder value while it decreases shareholder value. This is consistent with the contingent claims view predicting that global diversification has a positive impact on bondholders’ wealth while it has a negative influence on shareholder value (i.e., global diversification discount). Overall, our results reveal that global diversification does not destroy firm value. Journal of International Business Studies (2006), 37, 352–371.

The efficacy of experimental interventions designed to reduce drinking among designated drivers.

Designated drivers are a popular strategy for avoiding drunk driving. However, studies have demonstrated that the strategy is often implemented poorly, resulting in diminished risk-reduction effectiveness. The purpose of this study was to test the efficacy of six interventions designed to reduce alcohol consumption among designated drivers. A total of 376 groups consisting of 1,412 pedestrians (57.8% men) were recruited as they crossed into Tijuana, Mexico, from San Diego, CA. Before crossing into Mexico, each group was assigned at random to one of six experimental conditions or to one control condition. The six interventions were designed to (1) cue the use of designated drivers, (2) change attitudes about designated drivers, (3) provide monetary rewards for driver sobriety, and (4) increase group supportive norms for proper designated driver use. Participant breath alcohol concentrations (BrACs) were collected before entering Mexico and on return to the United States. Using group members to deliver pro-designated driver messages significantly decreased driver and passenger BrACs relative to controls. Male drivers were more likely to return from Mexico with BrACs of zero if they were rewarded. Among female drivers, wearing a bracelet with the printed words "designated driver" in addition to cuing resulted in 9 of 10 drivers returning with BrACs equal to zero. These results demonstrate that designated driver sobriety can be enhanced through brief interventions, and proper use of the designated driver concept did not increase the risk of excessive alcohol consumption for passengers.

Reducing risk exposures to zero and not having multiple partners: findings that inform evidence-based practices designed to prevent STD acquisition

Our objective was to assess prospectively the relative contribution of reducing penile-vaginal risk exposure to zero and limiting the number of sex partners to one, on the acquisition of biologically confirmed sexually transmitted disease (STD) among African American women adolescents. Data from a prospective cohort of 522 African American women adolescents enrolled in an HIV prevention trial were used. Baseline STD testing and single-dose directly observable treatment provided an infection-free cohort, who were followed and assessed at six-month intervals. Self-administered vaginal swab specimens were tested for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis at baseline, six, 12, and 18 months. Frequency of having multiple sex partners and unprotected vaginal sex over each six-month assessment interval was measured. Adolescents who reported multiple sex partners, relative to only one partner, were more likely to test positive for an STD (adjusted odds ratio (AOR) = 2.9; P = 0.0001). Adolescents who reported unprotected vaginal sex relative to those reporting protected vaginal sex also had greater odds of testing positive for an STD (AOR = 1.5; P = 0.0001). Prospective findings suggest that having multiple sex partners and engaging in unprotected vaginal sex both remain significant risk factors for STD acquisition among African American adolescent women. STD prevention programmmes need to target both risk factors to achieve optimal risk-reduction effectiveness.

Multiple predator effects in an intertidal food web

1. We examined the effects of multiple predators from an intertidal boulder food web to test whether and how three different predator species affected the survival of a small amphipod species. 2. Predators were chosen because they differ in their foraging mode, two feeding at the bottom and in benthic refuges (nemertean and shrimp) and one in the water-column (juveniles of a fish). 3. Mortality of amphipods was not affected by nemerteans, but was high in the presence of shrimp or fish. Highest mortalities were observed in predator-combinations that contained both shrimp and fish. Amphipods responded to shrimp by escaping into the water column, while they avoided fish by remaining in the refuge. We conclude that predator-specific defence causes conflicts for prey when both shrimp and fish are present. 4. Comparing observed effects of multiple predators with expected effects revealed risk enhancement for the shrimp + fish combination. A comparison of different predictive models revealed that the multiplicative model was most appropriate, although additive models may work well under certain conditions. 5. Based on known consumption-ranges of the predators used, we conclude that nemerteans were saturated with prey while fish were far from their saturation point. A predator's functional response curve (prey consumption in relation to prey abundance) determines its impact on prey populations. This knowledge appears essential in order to predict whether prey organisms face risk enhancement, risk reduction or additive effects of multiple predators.

Interventions to reduce the sexual risk behaviour of injecting drug users

Reducing the risk of sexual HIV transmission by injecting drug users (IDUs) is important for controlling the HIV epidemic among all drug users and for controlling the larger epidemic. Over the past few years, several qualitative and meta-analyses reviews have been published. Most of these reviews involved numerous studies conducted in resource-rich countries, while a few covered the smaller number of studies undertaken in resource-constrained countries. In order to make greater strides in controlling the HIV epidemic, we assessed the generalisability of the results of the major studies and reviews for use in developing programmes in resource-constrained countries. We also discuss the implications for global research efforts and public health practice. The reviews show that IDUs in both resource-rich and resource-constrained countries have changed their sexual risk behaviours, reflecting rational and altruistic responses to a major health threat. Findings show that IDUs changed their sexual risk behaviour to avoid becoming infected with HIV and to avoid transmitting HIV to their sexual partners. Although the risk-reduction effect is moderate, it is important to implement programmes to reduce the sexual risk behaviour of IDUs in all countries. Providing evidence-based interventions is ethically responsible compared to providing no interventions. As interventions are implemented in different settings, it is important to bear in mind that stigmatisation of HIV/AIDS, or drug or condom use may limit an intervention's effectiveness. There is a need for research on adapting interventions to different cultural or national settings, and to develop and evaluate new interventions that may produce greater reductions in sexual risk behaviours.

The use and abuse of the hedging effectiveness measure

Ederington (1979) proposed an effectiveness measure for futures hedging. Since then, this measure has been widely adopted in the literature to compare different hedge ratios against the OLS (ordinary least squares) hedge ratio. This note attempts to demonstrate this application is inappropriate. Ederington hedging effectiveness is only useful for measuring the risk reduction effect of the OLS hedge ratio. It does not apply to other hedge ratios and therefore should not serve as a criterion to compare different hedge strategies against the OLS strategy. A strict application of this measure almost always leads to an incorrect conclusion stating that the OLS hedge ratio is the best hedging strategy.

The effect of valsartan on regression of left ventricular hypertrophy in type 2 diabetic patients.

The aim of the present study was to examine the effects of an angiotensin II receptor antagonist, valsartan, on echocardiographically proven left ventricular hypertrophy (LVH) in patients with type 2 diabetes. Outpatients with type 2 diabetes mellitus were recruited at Niigata University Hospital. The left ventricular mass index (LVMI) was calculated by echocardiography. LVH was considered to be present if the LVMI was > 131 g/m(2) in males and > 100 g/m(2) in females. Patients with LVH received a low dose (40 mg/day) of valsartan for 12 months. This low dose had no clinical effect on blood pressure. Of the 38 patients who entered the study, 14 (36.8%) had LVH. After only 6 months of valsartan therapy, the mean LVMI decreased significantly, from 126.5 +/- 27.8 to 119.0 +/- 23.5 g/m(2) (p < 0.01 vs. baseline). Also, a significant decrease was observed after 12 months (116.5 +/- 30.9 g/m(2), p < 0.05 vs. baseline). Compared to baseline, there were no significant differences after treatment in body mass index, glycosylated haemoglobin (HbA(1c)), systolic blood pressure and diastolic blood pressure. In type 2 diabetic patients with LVH, treatment with a low dose of valsartan, an angiotensin II receptor antagonist, for 12 months, reduced LVMI, with no reduction in systemic blood pressure. This drug may be safely administered to type 2 diabetic patients with LVH. The long-term risk-reduction effects will have to be evaluated in further trials.

Sapporo Fitness Club Trial (SFCT)-Design, Recruitment and Implementation of a Randomized Controlled Trial to Test the Efficacy of Exercise at a Fitness Club for the Reduction of Cardiovascular Risk Factors-

The annual health check followed by lifestyle recommendations has long been the standard national strategy to improve cardiovascular disease (CVD) risk factors in Japan. Exercise at fitness clubs, now widely accessible in major cities, has a novel appeal as a strategy with the additive effect of CVD risk reduction. The Sapporo Fitness Club Trial (SFCT) is a randomized controlled trial to compare the efficacy of the national standard alone (control) with the standard plus exercise at a fitness club (intervention) for the reduction of CVD risk factors. The SFCT has recruited and randomized 561 relatively inactive overweight men and women, aged 40-85 years, with elevated levels of 2 or more of the following: systolic blood pressure, fasting blood glucose, and low-density lipoprotein cholesterol. The intervention group was required to exercise at a fitness club 2-4 times per week. At the end of 6 months, risk factors, aerobic capacity, health-related quality of life measures, and adverse effects are to be compared. The SFCT is expected to have a major impact in Japan on public health recommendations on exercise for the reduction of lifestyle-related disease.