Children living in areas with more street trees have lower prevalence of asthma.

BACKGROUND: The prevalence of childhood asthma in the USA increased by 50% from 1980 to 2000, with especially high prevalence in poor urban communities. METHODS: Data on the prevalence of asthma among children aged 4-5 years and on hospitalisations for asthma among children less than 15 years old were available for 42 health service catchment areas within New York City. Street tree counts were provided by the New York City Department of Parks and Recreation. The proximity to pollution sources, sociodemographic characteristics and population density for each area were also measured. RESULTS: Controlling for potential confounders, an increase in tree density of 1 standard deviation (SD, 343 trees/km(2)) was associated with a lower prevalence of asthma (RR, 0.71 per SD of tree density; 95% CI, 0.64 to 0.79), but not with hospitalisations for asthma (RR, 0.89 per SD of tree density; 95% CI, 0.75 to 1.06). CONCLUSIONS: Street trees were associated with a lower prevalence of early childhood asthma. This study does not permit inference that trees are causally related to asthma at the individual level. The PlaNYC sustainability initiative, which includes a commitment to plant one million trees by the year 2017, offers an opportunity for a large prospective evaluation.

Physicians' decisions to limit Medicaid participation: determinants and policy implications.

Although most primary care physicians participate in state Medicaid programs, they may accept all Medicaid patients, or they may choose to limit their participation. This decision allows physicians to adjust their Medicaid caseloads to a desired level, and it has important implications for the access of low-income patients to health care. Surveys of pediatricians in 1978 and 1983 indicate that the proportion of pediatricians limiting their Medicaid participation increased significantly from 26 percent to 35 percent (p less than .001). In addition, in both 1978 and 1983, limited participants saw significantly fewer Medicaid patients than full participants. This paper describes a number of strategies available to federal and state policymakers for fostering full Medicaid participation. Multivariate analyses indicate that increasing reimbursement levels is an important strategy for encouraging full Medicaid participation. In addition, full participants will increase their Medicaid caseloads in response to a variety of Medicaid policy incentives, while limited participants are found to respond to fewer policy incentives. The authors conclude that caution will be needed to ensure that health care cost-containment strategies such as capitation or selective contracting do not inadvertently discourage participation among both full and limited Medicaid participants.

Recent trends in pediatrician participation in Medicaid.

Many Medicaid policy changes occurred in recent years including those resulting from the Omnibus Budget Reconciliation Act of 1981 and the Tax Equity and Fiscal Responsibility Act of 1982. At the same time, the supply of providers increased and the health care market became more competitive. This paper presents evidence about how these developments are affecting pediatricians' participation in state Medicaid programs. Surveys conducted in 1978 (N = 814) and 1983 (N = 791) indicate that the proportion participating declined only slightly from 85.1% to 82.0%. The average Medicaid case load of participants remained at 15%, although extent of participation of individual pediatricians fluctuated. Previous research demonstrates that physicians' Medicaid participation is affected by reimbursement level, administrative complexity, and generosity of eligibility and benefits. Our data confirm these influences. However, the longitudinal design of the analyses reported here also captures shifts in the relative influence of these factors. The influence of policy factors has diminished over time, while the influence of changes in physician supply has increased. Increased physician supply, however, is associated with decreased Medicaid participation. Thus, diminished access to pediatric care for low-income children may result from recent changes in Medicaid and in the broader health care environment.