摘要:

There is currently no well‐accepted standard method for evaluation of developmental toxicity data. This paper presents one approach to the evaluation of developmental toxicity data. We initially identify some pertinent factors that influence the interpretation of animal data and summarize the literature pertaining to these factors. Such factors include the quality and quantity of data and the relationship between maternal and developmental toxicity. We proceed with a discussion of quantitative assessment of data and propose schemes for qualitative and quantitative developmental hazard assessment

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01154.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Many different techniques have been proposed for performing uncertainty and sensitivity analyses on computer models for complex processes. The objective of the present study is to investigate the applicability of three widely used techniques to three computer models having large uncertainties and varying degrees of complexity in order to highlight some of the problem areas that must be addressed in actual applications. The following approaches to uncertainty and sensitivity analysis are considered: (1) response surface methodology based on input determined from a fractional factorial design; (2) Latin hypercube sampling with and without regression analysis; and (3) differential analysis. These techniques are investigated with respect to (1) ease of implementation, (2) flexibility, (3) estimation of the cumulative distribution function of the output, and (4) adaptability to different methods of sensitivity analysis. With respect to these criteria, the technique using Latin hypercube sampling and regression analysis had the best overall performance. The models used in the investigation are well documented, thus making it possible for researchers to make comparisons of other techniques with the results in this study.

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01155.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

The issue of how to think about “uncertainty about probability” is framed and analyzed from the viewpoint of a decision analyst. The failure of nuclear power plants is used as an example. The key idea is to think of probability as describing a state of information on an uncertain event, and to pose the issue of uncertainty in this quantity as uncertainty about a number that would be definitive: it has the property that you would assign it as the probability if you knew it. Logical consistency requires that the probability to assign to a single occurrence in the absence of further information be the mean of the distribution of this definitive number, not the median as is sometimes suggested. Any decision that must be made without the benefit of further information must also be made using the mean of the definitive number's distribution. With this formulation, we find further that the probability of r occurrences in n exchangeable trials will depend on the first n moments of the definitive number's distribution. In making decisions, the expected value of clairvoyance on the occurrence of the event must be at least as great as that on the definitive number. If one of the events in question occurs, then the increase in probability of another such event is readily computed. This means, in terms of coin tossing, that unless one is absolutely sure of the fairness of a coin, seeing a head must increase the probability of heads, in distinction to usual thought. A numerical example for nuclear power shows that the failure of one plant of a group with a low probability of failure can significantly increase the probability that must be assigned to failure of a second plant in the gr

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01156.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Arapid screening ofhazard method (RASH) is presented for deriving relative potency estimates for hazardous substances. The method utilizes data from any available toxicological database such as the Registry of Toxic Effects of Chemical Substances (RTECS) or EPA's GENE‐TOX database on genetic activity profiles. The method has been applied to derive relative potency values and permissible environmental concentrations for 278 chemicals. The derived values have been compared with recommendations of expert committees where possible, and substantial agreement is foun

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01157.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

This paper reexamines the scaling approaches used in cancer risk assessment and proposes a more precise body weight scaling factor. Two approaches are conventionally used in scaling exposure and dose from experimental animals to man: body weight scaling (used by FDA) and surface area scaling (BW0.67—used by EPA). This paper reanalyzes the Freireichet al.(1966) study of the maximum tolerated dose (MTD) of 14 anticancer agents in mice, rats, dogs, monkeys, and humans, the dataset most commonly cited as justification for surface area extrapolation. This examination was augmented with an analysis of a similar dataset by Scheinet al.(1970) of the MTD of 13 additional chemotherapy agents. The reanalysis shows that BW0.75is a more appropriate scaling factor for the 27 direct‐acting compounds in this data

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01158.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Automobile accident risks vary significantly across populations, places, and times. This study describes the time‐varying pattern of societal risk. The relative risks of occupant fatality per person‐mile of travel are estimated here for each hour of the week, using 1983 data. The results exhibit a strong time‐of‐day effect and have a highly skewed frequency distribution, implying wide variations in risk‐taking behavior. Indeed, the 168 hourly estimates ranged from a low of 0.32 times the average around Sunday noon to a high of 43 times the average at 3:00 a.m. on Sunday, i.e., by a factor of 134 from bottom to top. Quantile‐quantile plots or “Lorenz curves,” introduced to display the unequal distribution of risks, show that approximately 34% of the vehicle occupant fatalities occur in hours representing only 5% of the travel. These findings have serious implications for risk analysis. First, when attempting to reconcile objective and subjective risk estimates, risk communicators should carefully control for when and to whom the risk in question is applicable. Second, comparisons of hazards on the basis of average risk are necessarily misleading for risks distributed so unevenly. Third, resource allocation decisions can benefit by knowing how incidence, exposure, and risk vary across time, place, and other relevant variables. Finally, certain cost‐benefit analyses that use average values to estimate risk exposure

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01159.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

In societal risk analysis the equity of the distribution of risks is often an important consideration owing to the special nature of health risks. We empirically validate some assumptions about equity that have been discussed in the decision analytic literature. Our results show that the way fatalities are distributed throughout a society is considered along with the number of fatalities in evaluating alternative policies involving mortality risks. The concepts ofex ante equityandex post equityare both shown to be important in judgments of fairness. We next present a decision model based on multiattribute preference theory incorporating the number of fatalities, as well asex anteequity andex postequity. Whenex anteequity andex postequity are positively weighted in thisfair‐risk model, options with more equal risk distributions are ranked higher. Next we empirically show that the distribution of benefits has an impact on judgments of fairness. The fair‐risk model does not include information on the benefits distribution, so it would apply when benefits are distributed equally or when the decision maker wishes to not include benefits in the model. We briefly discuss how the notion ofproportional equitycan incorporate benefits into judgments of the fairness of risk distributions. We then include benefits in a more general model in which fair risk‐benefit combinations are those that areexchange equitable.A key implication of thisenvy‐free risk–benefit modelis that an unequal distribution of risks may be preferred if it is accompanied by a compensatory differential in benefits consistent with peoples' preference tradeoffs between received benefits and assumed risks. Finally, we discuss how perceiveddeservednessmay influence judgments about equity. We conclude with a discussion of the implications of research on alternative notions of equity for policy makers dealing with soc

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01160.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

One way to communicate about the risks of drugs is through the use of package inserts. The problems associated with this medium of informing patients have been investigated by several researchers who found that people require information about drugs they are using, including extensive risk information, and that they are willing to take this information into account in their usage of drugs. But empirical results also show that people easily misinterpret the information given. A conceptual framework is proposed that might be used for better understanding the cognitive processes involved in such a type of risk assessment and communication. It is based on the idea that people develop, through experience, a mental model of how a drug works, which effects it might produce, that contraindications have to be considered, etc. This mental model is “run” when a specific package insert has been read and a specific question arises such as, for example, whether certain symptoms can be explained as normal or whether they require special attention and action. We argue that the mental model approach offers a useful perspective for examining how people understand package inserts, and consequently for improving their content and design. The approach promises to be equally useful for other aspects of risk analysis that are dependent upon human judgment and decision making, e.g., threat diagnosis and human reliability analy

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01161.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01162.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Books Reviewed in this Article:UNCERTAINTY IN RISK ASSESSMENT, RISK MANAGEMENT, AND DECISION MAKING Vincent T. Covello, Lester B. Lave, Alan Moghissi, and V. R. R. Uppuluri (eds.)SCIENTIFIC EXCELLENCE: ORIGINS AND ASSESSMENT Douglas N. Jackson and J. Phillippe Rushton (eds.)DRINKING WATER AND HEALTH: DISINFECTANTS AND DISINFECTANT BY‐PRODUCTS, VOL. 7 Subcommittee on Disinfectants and Disinfectant By‐Products, Safe Drinking Water CommitteeLEARNING ABOUT RISK: CONSUMER AND WORKER RESPONSES TO HAZARD INFORMATION W. Kip Viscusi and Wesley A. Magat with Joel Huber, Charles O. Connor, James R. Bettman, John W. Payne, and Richard StaelinTOXIC HAZARD ASSESSMENT OF CHEMICALS Mervyn Richardson (ed.)MANAGING RISK: SYSTEMATIC LOSS PREVENTION FOR EXECUTIVES Vernon L. G

ISSN:0272-4332    

DOI:10.1111/j.1539-6924.1988.tb01163.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY