Is the Gene-Environment Interaction Paradigm Relevant to Genome-Wide Studies? The Case of Education and Body Mass Index

This study uses data from the Framingham Heart Study to examine the relevance of the gene-environment interaction paradigm for genome-wide association studies (GWAS). We use completed college education as our environmental measure and estimate the interactive effect of genotype and education on body mass index (BMI) using 260,402 single-nucleotide polymorphisms (SNPs). Our results highlight the sensitivity of parameter estimates obtained from GWAS models and the difficulty of framing genome-wide results using the existing gene-environment interaction typology. We argue that SNP-environment interactions across the human genome are not likely to provide consistent evidence regarding genetic influences on health that differ by environment. Nevertheless, genome-wide data contain rich information about individual respondents, and we demonstrate the utility of this type of data. We highlight the fact that GWAS is just one use of genome-wide data, and we encourage demographers to develop methods that incorporate this vast amount of information from respondents into their analyses.     

A fast Monte Carlo expectation–maximization algorithm for estimation in latent class model analysis with an application to assess diagnostic accuracy for cervical neoplasia in women with atypical glandular cells

In this article, we use a latent class model (LCM) with prevalence modeled as a function of covariates to assess diagnostic test accuracy in situations where the true disease status is not observed, but observations on three or more conditionally independent diagnostic tests are available. A fast Monte Carlo expectation–maximization (MCEM) algorithm with binary (disease) diagnostic data is implemented to estimate parameters of interest; namely, sensitivity, specificity, and prevalence of the disease as a function of covariates. To obtain standard errors for confidence interval construction of estimated parameters, the missing information principle is applied to adjust information matrix estimates. We compare the adjusted information matrix-based standard error estimates with the bootstrap standard error estimates both obtained using the fast MCEM algorithm through an extensive Monte Carlo study. Simulation demonstrates that the adjusted information matrix approach estimates the standard error similarly with the bootstrap methods under certain scenarios. The bootstrap percentile intervals have satisfactory coverage probabilities. We then apply the LCM analysis to a real data set of 122 subjects from a Gynecologic Oncology Group study of significant cervical lesion diagnosis in women with atypical glandular cells of undetermined significance to compare the diagnostic accuracy of a histology-based evaluation, a carbonic anhydrase-IX biomarker-based test and a human papillomavirus DNA test.     

Private Polls and Presidential Policymaking: Reagan as a Facilitator of Change

Did the Reagan administration disregard majority will when craftingits policy initiatives? Did it cater to a narrow partisan constituencyinstead? The answers to these questions will help with an assessmentof Jacobs and Shapiro’s (2000b) hypothesis that presidentssince the late 1970s have used private White House survey researchas a tool to manipulate or assuage centrist public opinion whilemeeting the policy demands of their partisan core supporters,resulting in a decline in presidential responsiveness to majoritywill. Using the actual surveys administered by Richard Wirthlin(Reagan’s pollster) between 1981 and 1983, this articlewill demonstrate the level of consistency between majority opinionon 129 policy issues and Reagan’s behavior through 1984,and it will explore the conditions under which the presidentwas more or less likely to respond to public preferences. Thedata reveal that the Reagan administration was constrained bythe popular will in predicable ways: if the policy issues wereabout domestic concerns, highly popular, and visible in themedia, then the administration acted in line with public preferencesmore than 70 percent of the time. Further, Reagan and his adviserswere selective in responding to party activists: they championedissues drawn from their conservative ideological agenda thatfit with the current tide in public opinion, while sidesteppingother issues dear to party activists that encountered strongmajority resistance. While I do not contest Jacobs and Shapiro’s(2000b) important observation that presidents often use surveyresearch to "craft talk" in an attempt to channel the publicdebate, the evidence here highlights how the president nonethelessremains constrained by the popular will, at least on domesticissues.     

Perinatal loss and parental grief: the challenge of ambiguity and disenfranchised grief

Following perinatal loss, a type of ambiguous loss, bereaved couples struggle with and experience distress due to various forms of ambiguity. Moreover, the juxtaposition of their grief with society's minimization often disenfranchises them from traditional grieving processes. The purpose of this study was to explore sources of ambiguity and disenfranchised grief related to perinatal loss. Audio-taped interviews with 13 bereaved couples at 2, 6, and 13 months following the death of their fetus or infant were analyzed. Several categories of ambiguity and disenfranchised grief emerged, pertaining to: (a) the viability of the pregnancy; (b) the physical process of pregnancy loss; (c) making arrangements for the remains; and (d) sharing the news. This study uncovers the many sources of ambiguity and disenfranchised grief that bereaved couples face in interactions with family, friends, society, and healthcare professionals. These insights may inform healthcare professionals in their attempts to ease distress related to perinatal loss.