Chip Shots: Association Between the State Children's Health Insurance Programs and Immunization Coverage and Delivery

By age two a child who is up to date for immunizations will have received up to 19 shots delivered over eight visits at a market cost of $525 dollars for the vaccines alone, a far more expensive and demanding regimen that the 8 shots received in 1987. In recognition of the potential importance of health insurance to immunization coverage rates, the State Children's Health Insurance Program (SCHIP) mandated that all plans cover the cost and administration of childhood vaccines. We use data from the recently released National Immunization Survey for the years 1995 to 2001 to test whether SCHIP was associated with differential changes among poor and near-poor children relative to their non-poor counterparts in either age-appropriate immunization rates or in the proportion of vaccines delivered by private providers. We show that the probability that a child was up to date for the varicella vaccine increased between 7 and 16 percentage points more among poor and near-poor relative to non-poor children after implementation of SCHIP. The increase was greater among children from urban areas, among Hispanics and among those from states with the highest rates of uninsured children prior to SCHIP than among children nationally. We found small to inconsequential changes for other vaccines. We also found that the probability that a poor or near-poor child obtained all vaccines at a private provider fell relative to the same probability among non-poor children over the study period. SCHIP appears to have affected the uptake of a recently introduced vaccine, which suggests that insurance coverage may be important for the rapid adoption of the latest and increasingly more expensive agents such as the pneumococcal conjugate vaccine.

The Effect of Cigarette Excise Taxes on Smoking Before, During and After Pregnancy

Recent analyses suggest that cigarette excise taxes lower prenatal smoking. It is unclear, however, whether the association between taxes and prenatal smoking represents a decline among women of reproductive age or a particular response by pregnant women. We address this question directly with an analysis of quit and relapse behavior during and after pregnancy. We find that the price elasticity of prenatal quitting and postpartum relapse is close to one in absolute value. We conclude that direct financial incentives to stop smoking during and after pregnancy should be considered.

Did Legalized Abortion Lower Crime?

This paper examines the relationship between the legalization of abortion and subsequent decreases in crime. In a current study, researchers estimate that the legalization of abortion explains over half of the recent decline in national crime rates. The association is identified by correlating changes in crime with changes in the abortion ratio weighted by the proportion of the criminal population exposed to legalized abortion. In this paper, I use an alternative identification strategy. I analyze changes in homicide and arrest rates among teens and young adults born before and after 1970 in states that legalized abortion prior to Roe v. Wade. I compare these changes with variation in homicide and arrest rates among cohorts from the same period but who were unexposed to legalized abortion. I find little evidence to support the claim that legalized abortion caused the reduction in crime. I conclude that the association between abortion and crime is not causal, but most likely the result of confounding from unmeasured period effects such as changes in crack cocaine use and its spillover effects.

The Changing Association Between Prenatal Participation in WIC and Birth Outcomes in New York City

We analyze the relationship between prenatal WIC participation and birth outcomes in New York City from 1988-2001. The analysis is unique for several reasons. First, we restrict the analysis to women on Medicaid and or WIC who have no previous live births and who initiate prenatal care within the first four months of pregnancy. Our goal is to lessen heterogeneity between WIC and non-WIC participants by limiting the sample to women who initiate prenatal care early and who have no experience with WIC from a previous pregnancy. Second, we focus on measures of fetal growth distinct from preterm birth, since there is little clinical support for a link between nutritional supplementation and premature delivery. Third, we analyze a large sub-sample of twin deliveries. Multifetal pregnancies increase the risk of anemia and fetal growth retardation and thus, may benefit more than singletons from nutritional supplementation. We find no relationship between prenatal WIC participation and measures of fetal growth except among a sub-sample of US-born Blacks between 1990-1992. A similarly sporadic pattern of association exists among US-born Black twins. Our finding that the modest association between WIC and fetal growth is limited to a specific racial and ethnic group during specific years and even specific ages suggests that the protective effect of prenatal WIC on adverse birth outcomes in New York City has been minimal.

Further Tests of Abortion and Crime

The inverse relationship between abortion and crime has spurred new research and much controversy. If the relationship is causal, then polices that increased abortion have generated enormous external benefits from reduced crime. In previous papers, I argued that evidence for a casual relationship is weak and incomplete. In this paper, I conduct a number of new analyses intended to address criticisms of my earlier work. First, I examine closely the effects of changes in abortion rates between 1971 and 1974. Changes in abortion rates during this period were dramatic, varied widely by state, had a demonstrable effect on fertility, and were more plausibly exogenous than changes in the late 1970s and early 1980s. If abortion reduced crime, crime should have fallen sharply as these post-legalization cohorts reached their late teens and early 20s, the peak ages of criminal involvement. It did not. Second, I conduct separate estimates for whites and blacks because the effect of legalized abortion on crime should have been much larger for blacks than whites, since the effect of legalization of abortion on the fertility rates of blacks was much larger. There was little race difference in the reduction in crime. Finally, I compare changes in homicide rates before and after legalization of abortion, within states, by single year of age. The analysis of older adults is compelling because they were largely unaffected by the crack-cocaine epidemic, which was a potentially important confounding factor in earlier estimates. These analyses provide little evidence that legalized abortion reduced crime.

Family Cap Provisions and Changes in Births and Abortions

As part of welfare reform efforts in the 1990s, twenty-three states implemented family caps, provisions that deny or reduce cash assistance to welfare recipients who have additional births. We use birth and abortion records from 24 states to estimate effects of family caps on birth and abortion rates. We use age, marital status and completed schooling to identify women at high risk for use of public assistance, and parity (number of previous live births) to identify those most directly affected by the family cap. In family cap states, birth rates fell more and abortion rates rose more among high-risk women with at least one previous live birth compared to similar childless women, consistent with an effect of the family cap. However, this parity-specific pattern of births and abortions also occurred in states that implemented welfare reform with no family cap. Thus, the effects of welfare reform may have differed between mothers and childless women, but there is little evidence of an independent effect of the family cap.

Placebos without Deception: A Randomized Controlled Trial in Irritable Bowel Syndrome

Background: Placebo treatment can significantly influence subjective symptoms. However, it is widely believed that response to placebo requires concealment or deception. We tested whether open-label placebo (non-deceptive and non-concealed administration) is superior to a no-treatment control with matched patient-provider interactions in the treatment of irritable bowel syndrome (IBS). Methods: Two-group, randomized, controlled three week trial (August 2009-April 2010) conducted at a single academic center, involving 80 primarily female (70%) patients, mean age 47±18 with IBS diagnosed by Rome III criteria and with a score ≥150 on the IBS Symptom Severity Scale (IBS-SSS). Patients were randomized to either open-label placebo pills presented as “placebo pills made of an inert substance, like sugar pills, that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body self-healing processes” or no-treatment controls with the same quality of interaction with providers. The primary outcome was IBS Global Improvement Scale (IBS-GIS). Secondary measures were IBS Symptom Severity Scale (IBS-SSS), IBS Adequate Relief (IBS-AR) and IBS Quality of Life (IBS-QoL). Findings: Open-label placebo produced significantly higher mean (±SD) global improvement scores (IBS-GIS) at both 11-day midpoint (5.2±1.0 vs. 4.0±1.1, p<.001) and at 21-day endpoint (5.0±1.5 vs. 3.9±1.3, p = .002). Significant results were also observed at both time points for reduced symptom severity (IBS-SSS, p = .008 and p = .03) and adequate relief (IBS-AR, p = .02 and p = .03); and a trend favoring open-label placebo was observed for quality of life (IBS-QoL) at the 21-day endpoint (p = .08). Conclusion: Placebos administered without deception may be an effective treatment for IBS. Further research is warranted in IBS, and perhaps other conditions, to elucidate whether physicians can benefit patients using placebos consistent with informed consent. Trial Registration ClinicalTrials.gov NCT0101019

The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity

We have made the largest-volume measurement to date of the transition to large-scale homogeneity in the distribution of galaxies. We use the WiggleZ survey, a spectroscopic survey of over 200,000 blue galaxies in a cosmic volume of ~1 (Gpc/h)^3. A new method of defining the 'homogeneity scale' is presented, which is more robust than methods previously used in the literature, and which can be easily compared between different surveys. Due to the large cosmic depth of WiggleZ (up to z=1) we are able to make the first measurement of the transition to homogeneity over a range of cosmic epochs. The mean number of galaxies N(<r) in spheres of comoving radius r is proportional to r^3 within 1%, or equivalently the fractal dimension of the sample is within 1% of D_2=3, at radii larger than 71 \pm 8 Mpc/h at z~0.2, 70 \pm 5 Mpc/h at z~0.4, 81 \pm 5 Mpc/h at z~0.6, and 75 \pm 4 Mpc/h at z~0.8. We demonstrate the robustness of our results against selection function effects, using a LCDM N-body simulation and a suite of inhomogeneous fractal distributions. The results are in excellent agreement with both the LCDM N-body simulation and an analytical LCDM prediction. We can exclude a fractal distribution with fractal dimension below D_2=2.97 on scales from ~80 Mpc/h up to the largest scales probed by our measurement, ~300 Mpc/h, at 99.99% confidence.Comment: 21 pages, 16 figures, accepted for publication in MNRA

Observation and integrated Earth-system science: a roadmap for 2016–2025

This report is the response to a request by the Committee on Space Research of the International Council for Science to prepare a roadmap on observation and integrated Earth-system science for the coming ten years. Its focus is on the combined use of observations and modelling to address the functioning, predictability and projected evolution of interacting components of the Earth system on timescales out to a century or so. It discusses how observations support integrated Earth-system science and its applications, and identifies planned enhancements to the contributing observing systems and other requirements for observations and their processing. All types of observation are considered, but emphasis is placed on those made from space. The origins and development of the integrated view of the Earth system are outlined, noting the interactions between the main components that lead to requirements for integrated science and modelling, and for the observations that guide and support them. What constitutes an Earth-system model is discussed. Summaries are given of key cycles within the Earth system. The nature of Earth observation and the arrangements for international coordination essential for effective operation of global observing systems are introduced. Instances are given of present types of observation, what is already on the roadmap for 2016–2025 and some of the issues to be faced. Observations that are organised on a systematic basis and observations that are made for process understanding and model development, or other research or demonstration purposes, are covered. Specific accounts are given for many of the variables of the Earth system. The current status and prospects for Earth-system modelling are summarized. The evolution towards applying Earth-system models for environmental monitoring and prediction as well as for climate simulation and projection is outlined. General aspects of the improvement of models, whether through refining the representations of processes that are already incorporated or through adding new processes or components, are discussed. Some important elements of Earth-system models are considered more fully. Data assimilation is discussed not only because it uses observations and models to generate datasets for monitoring the Earth system and for initiating and evaluating predictions, in particular through reanalysis, but also because of the feedback it provides on the quality of both the observations and the models employed. Inverse methods for surface-flux or model-parameter estimation are also covered. Reviews are given of the way observations and the processed datasets based on them are used for evaluating models, and of the combined use of observations and models for monitoring and interpreting the behaviour of the Earth system and for predicting and projecting its future. A set of concluding discussions covers general developmental needs, requirements for continuity of space-based observing systems, further long-term requirements for observations and other data, technological advances and data challenges, and the importance of enhanced international co-operation

The Collapse of Exotic Textures

The ordering of scalar fields after a phase transition in which a group $G$ of global symmetries is spontaneously broken to a subgroup $H$ provides a possible explanation for the origin of structure in the universe, as well as leading to observable effects in condensed matter systems. The field dynamics can depend in principle on the geometry and topology of the vacuum manifold G/H; for example, texture configurations which collapse and unwind will exist if the third homotopy group $\pi_3(G/H)$ is nontrivial. We numerically simulate the evolution of texture-like configurations in a number of different models, in order to determine the extent to which the geometry and topology of the vacuum manifold influences the field evolution. We find that the dynamics is affected by whether or not the theory supports strings or monopoles [characterized by $\pi_1(G/H)$ and $\pi_2(G/H)$, respectively]. In some of the theories studied, configurations with initially spherically symmetric energy densities are unstable to nonspherical collapse; these theories are also found to nucleate defects during the collapse. Models that do not support monopoles or strings behave similarly to each other, regardless of the specific vacuum manifold.Comment: 28 pages plus 10 figures. Additional figures and mpeg movies accessible from http://itp.ucsb.edu/~carroll/textures.htm