Foundations for the Illusion of Certainty Pertaining to Health Risks and Benefits

Paper presented at the 1st International Symposium on Understanding Health Benefits and Risks: Empowering Patients and Citizens. Johns Hopkins University, Baltimore, Maryland. May 29, 2009Health benefits and risks are part of our everyday language and get extensive media coverage. Daily we are presented with information about effects from exposure to environmental contaminants and reports from public health and medical groups about the benefits and risks from medical screening tests and drugs. Are these statements accurate? If so, are they meaningful? We seek medical intervention and make dramatic lifestyle changes hoping they will provide benefits. The management of environmental contamination and exposures involves costs. The benefit and risk statements are usually presented as if they are authoritative, definitive, and based on clear and unequivocal evidence. This leads to an illusion of certainty. Risk assessment is a valid and important scientific discipline, but the uncertainty in this process tends to be forgotten. Unfortunately, ignoring uncertainty has serious results: errors of interpretation, communication of misleading information, even dissemination of deceptive statements. The chance of a health benefit or risk can be reported as a relative number or an absolute number. It can be presented as a rate, probability, or the cause of a positive or adverse effect. Since the use of risk assessment has become common-place, proper interpretation of health benefit and risk values is essential. The goal of this presentation is to provide an understanding and appreciation of the risk assessment process and to provide tools to interpret health benefit and risk values objectively. Included will be an explanation of the uncertainty inherent in the assessment of health benefits and risks, as well as an explanation of how communication and characterization can dramatically alter how these benefits and risks are perceived. An innovative and straight-forward visual aid (RCT:Risk Characterization Theater) will be used to explain the benefits of medical screening tests (e.g., mammography, prostate and colorectal cancer screening, cholesterol screening) and drugs (e.g., statins, Vioxx) and the risks associated with exposure to environmental contaminants (e.g., drinking water pathogens and radon). The intent of this presentation is to help patients and their families get more involved in making medical decisions, and citizens face critical questions about the environment. By putting the complexities of risk analysis in terms the general public can relate to, the principles presented in this talk will empower people to make well-informed decisions

Disorganized Attachment in Infancy: A Review of the Phenomenon and Its Implications for Clinicians and Policy-Makers

Disorganized/Disoriented (D) attachment has seen widespread interest from policy makers, practitioners, and clinicians in recent years. However, some of this interest seems to have been based on some false assumptions that (1) attachment measures can be used as definitive assessments of the individual in forensic/child protection settings and that disorganized attachment (2) reliably indicates child maltreatment, (3) is a strong predictor of pathology, and (4) represents a fixed or static trait of the child, impervious to development or help. This paper summarizes the evidence showing that these four assumptions are false and misleading. The paper reviews what is known about disorganized infant attachment and clarifies the implications of the classification for clinical and welfare practice with children. In particular, the difference between disorganized attachment and attachment disorder is examined, and a strong case is made for the value of attachment theory for supportive work with families and for the development and evaluation of evidence-based caregiving interventions

Variability in gene expression underlies incomplete penetrance

The phenotypic differences between individual organisms can often be ascribed to underlying genetic and environmental variation. However, even genetically identical organisms in homogeneous environments vary, indicating that randomness in developmental processes such as gene expression may also generate diversity. To examine the consequences of gene expression variability in multicellular organisms, we studied intestinal specification in the nematode Caenorhabditis elegans in which wild-type cell fate is invariant and controlled by a small transcriptional network. Mutations in elements of this network can have indeterminate effects: some mutant embryos fail to develop intestinal cells, whereas others produce intestinal precursors. By counting transcripts of the genes in this network in individual embryos, we show that the expression of an otherwise redundant gene becomes highly variable in the mutants and that this variation is subjected to a threshold, producing an ON/OFF expression pattern of the master regulatory gene of intestinal differentiation. Our results demonstrate that mutations in developmental networks can expose otherwise buffered stochastic variability in gene expression, leading to pronounced phenotypic variation.National Institutes of Health (U.S.). Pioneer AwardMathematical Sciences Postdoctoral Research Fellowships (DMS-0603392)National Institutes of Health (U.S.). Ruth L. Kirschstein National Research Service Award (5F32GM080966

The internal defense mechanisms of the oyster, Crassostrea virginica, in response to the cestode Tylocephalem sp

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Understanding the Concept of Acceptable Health Risks and Benefits

Paper presented at the 1st International Symposium on Understanding Health Benefits and Risks: Empowering Patients and Citizens. Johns Hopkins University, Baltimore, Maryland. May 29, 2009The notion of acceptable health risks or benefits is not easy to define. Acceptable risk is essentially the measure of harm or disease that is considered acceptable by a person or an organization (e.g., EPA, CDC, FDA). Whether a risk is acceptable depends upon the benefits derived from taking the risk, the magnitude of the risk, and various economic, political and social factors. We tend to rely on others when we have to determine acceptable health risks, be they risks from exposure to contaminants, or risks and benefits from screening tests and drugs. We often assume that experts in environmental science, biology, medicine, statistics and other disciplines are more qualified to make decisions as to what constitutes an acceptable health risk or benefit. Why don’t we want to make our own decisions? Largely because there is a prevailing view that acceptable risk values are based on the analysis and interpretation of scientific data and results. But this is simply not the case. Acceptable risks and benefits are based, in large part, on public acceptance, political agenda and economic considerations. It may seem counterintuitive, but there is no science involved in this process. Having the proper data available in a user-friendly format will enable each of us to determine the level of benefits and risks which we are willing to accept. We have a right to this information, and an acknowledgement of this right will serve to empower patients and citizens. This presentation will use specific examples (e.g., cancer screening tests, lowering cholesterol, exposure to environmental contaminants) and a unique graphic (Risk Characterization Theater) to illustrate how patients and citizens can become empowered to determine their own level of acceptable risk

Studies on the Internal Defense Mechanisms of Sponges: I. The Cell Types Occurring in the Mesoglea of Terpios zeteki (de Laubenfels) (Porifera: Demospongiae)

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