Heterogeneity in treatment effects across diverse populations

Differences in patient characteristics, including age, sex, and race influence the safety and effectiveness of drugs, biologic products, and medical devices. Here we provide a summary of the topics discussed during the opening panel at the 2018 Johns Hopkins Center for Excellence in Regulatory Science and Innovation symposium on Assessing and Communicating Heterogeneity of Treatment Effects for Patient Subpopulations: Challenges and Opportunities. The goal of this session was to provide a brief overview of FDA-regulated therapeutics, including drugs, biologics and medical devices, and some of the major sources of heterogeneity of treatment effects (HTE) related to patient demographics, such as age, sex and race. The panel discussed the US Food and Drug Administration's role in reviewing and regulating drugs, devices, and biologic products and the challenges associated with ensuring that diverse patient populations benefit from these therapeutics. Ultimately, ensuring diverse demographic inclusion in clinical trials, and designing basic and clinical research studies to account for the intended patient population's age, sex, race, and genetic factors among other characteristics, will lead to better, safer therapies for diverse patient populations.     

Commercial sex between men: A prospective diary‐based study

This paper describes the results of a self‐reporting dairy completed by 186 male sex workers (MSWs) over a 2‐week period in Brisbane, Sydney, and Melbourne, Australia. The diary was completed following each commercial sex encounter by the MSW. The results reveal that MSWs reported 2088 commercial sex encounters during the study period, with an average of 11.2 encounters per MSW. The majority of sex encounters took place in either the client's or the MSW's residence, with significant variations by city. The average sexual encounter lasted 70 minutes, and comprised two sexual acts, masturbation and oral sex. Condom use was reported in 67.4% of all the encounters. Using the AIDS Council safe‐sex classification system, the majority of the commercial sex encounters fell in the “safer sex” category; however, there were significant differences by source of clients and place of the encounter. Use of drugs and alcohol reveal interesting patterns: Clients were more likely to use alcohol, while MSWs had significant differences of usage of the different drugs. This study demonstrates that the majority of MSWs are offering and practicing safe sex behaviours, however, MSWs working in the street setting are still likely to be practising unsafe sex. Male sex work is becoming an organised business and this provides opportunities to implement further public health interventions.     

The Social Structuring of Mental Health over the Adult Life Course: Advancing Theory in the Sociology of Aging

The sociology of aging draws on a broad array of theoretical perspectives from several disciplines, but rarely has it developed its own. We build on past work to advance and empirically test a model of mental health framed in terms of structural theorizing and situated within the life course perspective. Whereas most prior research has been based on cross-sectional data, we utilize four waves of data from a nationally representative sample of American adults (Americans' Changing Lives Study) collected prospectively over a 15-year period and find that education, employment and marital status, as well as their consequences for income and health, effectively explain the increase in depressive symptoms after age 65. We also found significant cohort differences in age trajectories of mental health that were partly explained by historical increases in education. We demonstrate that a purely structural theory can take us far in explaining later life mental health.     

Say Yes First: follow up of a five-year rural drug prevention program

Say Yes First--To Rural Youth and Family Alcohol/Drug Prevention (SYF) was a 5-year, federally-funded U.S.D.H.H.S. Center for Substance Abuse Prevention (CSAP) project that involved 859 children in the class of the year 2000. The children in four rural school districts were followed from Grade 4 to Grade 8 from 1991 to 1996. Initial results in a previous publication showed significant lower drug usage in this cohort than comparison students. A follow-up of 120 SYF participants and 136 comparison students in high schools using the National Youth Survey (Follow Up Questionnaire) indicated lower usage of alcohol, tobacco and other drugs for the program students and lower lifetime prevalence of marijuana use for program vs. comparison students. SYF students had higher course grades, lower school absenteeism, more positive attitudes toward school, less trouble in school and less negative self-appraisal. Program students also reported greater participation in sports, more family communication and fewer disagreements or arguments with their parents.     

Ask Prices, Offers, and Time to Sale in an Online Exchange

By examining an online computer exchange, we find that sellers who place higher nonbinding ask prices have higher outstanding offers and remain on the exchange longer, suggesting a willingness to hold out for higher offers. Additionally, higher ask prices deter buyers from making offers. The results are stronger in thinner market segments, suggesting that gains from waiting for a high price are greater when buyers' tastes are idiosyncratic. These relationships are consistent with models in which buyers engage in costly search and suggest that online exchanges may not eliminate the frictions related to bilateral transactions.