The inclusion of minority groups in clinical trials: problems of under representation and under reporting of data

Objective: To evaluate the representation of minority groups in randomized control trials (RCTs), and the frequency with which this information is reported. Study Design: Reviewers collected data on the racial/ethnic composition of study samples from all RCTs published in six leading medical journals in 1999. Results: Of the 280 RCTs, most (204, 71.3%) provided no information on the race/ethnicity of participants. Of the 89 U.S.-based RCTs, 50 (56.1%) reported their minority distribution. Relative to other trials, those funded by the National Institute of Health (NIH) (n = 52) were more likely to report race/ethnicity data (55.8% vs. 23.7%; x2 = 20.9, p <_0.001) and to include nonwhite participants (13.5 % vs. 12.5%; x2=22.7, p<_0.001). Conclusion: Minority groups are currently under-represented in clinical trials. Information on the race and ethnicity of clinical trial participants is currently underreported in six leading medical journals. Reporting of minority group information was significantly better only in NIH funded trials, which also were more likely to include nonwhite participants. This suggests that mandatory reporting policies may have a positive effect on both reporting and representation.     

The reasonable man — a social choice approach

Most legal systems rely heavily on the notion of the reasonable man. Here an attempt is made to analyze the reasonable man in a social choice model. The main argument is that if the reasonable man satisfies a certain set of axioms, he essentially coincides with one of the individuals, both in terms of his preferences and in terms of his expectations.     

The Importance of Early Childhood Poverty

Most poor children achieve less, exhibit more problem behaviors and are less healthy than children reared in more affluent families. We look beyond correlations such as these to a recent set of studies that attempt to assess the causal impact of childhood poverty on adult well-being. We pay particular attention to the potentially harmful effects of poverty early in childhood on adult labor market success (as measured by earnings), but also show results for other outcomes, including out-of-wedlock childbearing, criminal arrests and health status. Evidence suggests that early poverty has substantial detrimental effects on adult earnings and work hours, but on neither general adult health nor such behavioral outcomes as out-of-wedlock childbearing and arrests. We discuss implications for indicators tracking child well-being as well as policies designed to promote the well-being of children.     

Stochastic Algorithms,Symmetric Markov Perfect Equilibrium,and the ‘curse’ of Dimensionality

This paper introduces a stochastic algorithm for computing symmetric Markov perfect equilibria. The algorithm computes equilibrium policy and value functions, and generates a transition kernel for the (stochastic) evolution of the state of the system. It has two features that together imply that it need not be subject to the curse of dimensionality. First, the integral that determines continuation values is never calculated; rather it is approximated by a simple average of returns from past outcomes of the algorithm, an approximation whose computational burden is not tied to the dimension of the state space. Second, iterations of the algorithm update value and policy functions at a single (rather than at all possible) points in the state space. Random draws from a distribution set by the updated policies determine the location of the next iteration's updates. This selection only repeatedly hits the recurrent class of points, a subset whose cardinality is not directly tied to that of the state space. Numerical results for industrial organization problems show that our algorithm can increase speed and decrease memory requirements by several orders of magnitude.     

USES OF CHILDREN'S MAKE-BELIEVE PLAY IN FAMILY THERAPY:THEORY AND CLINICAL EXAMPLES

A theoretical framework for developing, describing and analyzing family-therapeutic techniques involving make-believe play is presented and illustrated by clinical examples. This theoretical framework includes specifications of the therapeutic goals served by the technique and its procedural details (the therapist's position and roles, the method of intervention, the sources of play content and means, and the amount of planning) and an analysis of its rationale (the properties of the make-believe play involved, the targets of the intervention in the family system, the expected changes and their causes). This framework draws on a definition of the concept "make-believe play," a model for the analysis of make-believe play symbols and a model of family systems, which are briefly sketched in this article, preceding the presentation of the theoretical framework itself.     

Quantitative Cancer Risk Estimation for Formaldehyde

Of primary concern are irreversible effects, such as cancer induction, that formaldehyde exposure could have on human health. Dose-response data from human exposure situations would provide the most solid foundation for risk assessment, avoiding problematic extrapolations from the health effects seen in nonhuman species. However, epidemiologic studies of human formaldehyde exposure have provided little definitive information regarding dose-response. Reliance must consequently be placed on laboratory animal evidence. An impressive array of data points to significantly nonlinear relationships between rodent tumor incidence and administered dose, and between target tissue dose and administered dose (the latter for both rodents and Rhesus monkeys) following exposure to formaldehyde by inhalation. Disproportionately less formaldehyde binds covalently to the DNA of nasal respiratory epithelium at low than at high airborne concentrations. Use of this internal measure of delivered dose in analyses of rodent bioassay nasal tumor response yields multistage model estimates of low-dose risk, both point and upper bound, that are lower than equivalent estimates based upon airborne formaldehyde concentration. In addition, risk estimates obtained for Rhesus monkeys appear at least 10-fold lower than corresponding estimates for identically exposed Fischer-344 rats.