Do public health activities pay for themselves? The effect of county-level public health expenditures on county-level public assistance medical care benefits in California.

This study estimates the effect of county-level public health expenditures in reducing county-level public assistance medical care benefits (public assistance medical care benefits is a measure compiled by the US Bureau of Economic Analysis and includes Medicaid and other medical vendor payments). The effect is modeled using a static panel model and estimated using two-stage limited information maximum likelihood and a valid instrumental variable. For every $1 invested in county-level public health expenditures, public assistance medical care benefits are reduced by an average of $3.12 (95% confidence interval: -$5.62, -$0.94). Because Medicaid in California is financed via an approximate 50% match of federal dollars with state dollars, savings to the state are approximately one-half of this, or $1.56 for every $1 invested in county-level public health expenditures.

How robust are reference pricing studies on outpatient medical procedures? Three different preprocessing techniques applied to difference-in differences.

The evaluation of policies that are not randomly assigned on outcomes generated by nonlinear data generating processes often requires modeling assumptions for which there is little theoretical guidance. This paper revisits previously published difference-in-differences results of an important example, the introduction of reference pricing to common outpatient procedures, to assess the robustness of the estimated impacts by using different matching, and reweighting techniques to preprocess the data. These techniques improve covariate balance and reduce model dependence. Specifically, we examine the robustness of the effect of reference pricing on patient site-of-care choice, total expenditures, and complication rates. We apply three preprocessing methods: propensity score reweighting, exact matching, and genetic matching. Propensity score reweighting is a technique for achieving covariate balance but does not balance higher-order moments and may lead to bias and inefficiency in estimating treatment effects in the context of nonlinear data generating processes. In contrast, exact matching and genetic matching are designed to balance higher-order moments. We find that although the use of the preprocessing techniques is a valuable robustness check showing that some results are sensitive to the method used, the three approaches generally yield results that do not statistically differ from the published results.

Evaluating the impact of California's full service partnership program using a multidimensional measure of outcomes.

This study evaluates the impact of California's full-service partnership (FSP) program using a multidimensional measure of outcomes. The FSP program is a key part of California's 2005 Mental Health Services Act. Secondary data were collected from the Consumer Perception Survey, the Client and Service Information System, and the Data Collection and Reporting System, all data systems which are maintained by the California Department of Mental Health. The analytic sample contained 39,681 observations of which 588 were FSP participants (seven repeated cross-sections from May 2005 to May 2008). We performed instrumental variables (IV) limited information maximum likelihood and IV Tobit analyses. The marginal monthly improvement in outcomes of services for FSP participants was approximately 3.5 % higher than those receiving usual care with the outcomes of the average individual in the program improving by 33.4 %. This shows that the FSP program is causally effective in improving outcomes among the seriously mentally ill.

The effect of dental care on cardiovascular disease outcomes: an application of instrumental variables in the presence of heterogeneity and self-selection.

Studies show a relationship between oral inflammatory processes and cardiovascular risk factors, suggesting that dental care may reduce the risk of cardiovascular disease (CVD) events. However, due to the differences between men and women in the development and presentation of CVD, such effects may vary by sex. We use a valid set of instrumental variables to evaluate these issues and include a test of essential heterogeneity. CVD events include new occurrences of heart attack (including death from heart attack), stroke (including death from stroke), angina, and congestive heart failure. Controls include age, race, education, marital status, foreign birthplace, and cardiovascular risk factors (health status, body mass index, alcohol use, smoking status, diabetes status, high-blood-pressure status, physical activity, and depression). Our analysis finds no evidence of essential heterogeneity. We find the minimum average treatment effect for women to be -0.01, but find no treatment effect for men. This suggests that women who receive dental care may reduce their risk of future CVD events by at least one-third. The findings may only apply to married middle-aged and older individuals as the data set is only representative for this group.

How effective are public health departments at preventing mortality?

This study estimates the causal impact of variation in the expenditures of California county departments of public health on all-cause mortality rates and the associated value of lives saved. Since the activities of county departments of public health are likely to affect mortality rates with a lag, Koyck distributed lag models are estimated using the Lewbel instrumental variables estimator. The findings show that an additional $10 per capita of public health expenditures reduces all-cause mortality by 9.1 deaths per 100,000. At current funding levels, the long-run annual number of lives saved by the presence of county departments of public health in California is estimated to be approximately 27,000 (26,937 lives, 95% confidence interval: [11,963, 41,911]). The annual value of these lives is estimated to be worth $212.8 billion using inflation-adjusted standard U.S. government estimates of the value of a statistical life ($7.9 million).

Voluntary psychiatric emergencies in Los Angeles County after funding of California's Mental Health Services Act.

OBJECTIVE: Since 2006, California's Mental Health Services Act (MHSA) has distributed an estimated $6 billion in new tax revenues to county mental health systems. Although evaluations of MHSA's effectiveness find favorable outcomes among high-risk individuals that represent 6% of all mental health clients, scant research has tested whether MHSA funds improve the overall functioning of the public mental health system. The authors analyzed whether the incidence of voluntary emergency psychiatric visits, a key gauge of the functioning of the mental health system, fell below expected levels after the disbursement of MHSA funds. Los Angeles County, the most populous county in California, was examined. METHODS: The authors obtained the monthly incidence of emergency psychiatric visits among Medi-Cal patients for 96 months spanning July 2000 to June 2008 (5.9 million overall admissions, of which 47,328 were emergency visits). Time-series methods controlled for temporal patterns in emergency visits as well as other potential confounders (unemployment, for example) that could induce spurious associations. RESULTS: The incidence of voluntary psychiatric emergencies fell below expected levels eight to 12 months after the disbursement of MHSA funds. After one year, emergency visits returned to their long-term mean level. Results remained robust after analyses controlled for outliers and potential confounders. CONCLUSIONS: In the short term, an infusion of public funds devoted to mental health services appeared to reduce psychiatric emergency visits. Explanations for the transient nature of the decline in emergency visits in Los Angeles County are discussed.

The impact of California's full-service partnership program on mental health-related emergency department visits.

OBJECTIVE: This study examined the effects of California's 2005 Mental Health Services Act (MHSA) on the use of mental health-related emergency department visits. It focused on one MHSA program, the full-service partnership program, and hypothesized that individuals with public insurance who participate in the higher-quality full-service partnership program would have fewer emergency department visits compared with clients with public insurance who receive usual care. METHODS: Data were obtained from the Short-Doyle/Medi-Cal (Medicaid) file, the Data Collection and Reporting system, and the Consumer and Service Information System, all maintained by the California Department of Mental Health. The analytic sample covered 931,218 observations (155,203 adults) ages 18 and older from January 2007 to June 2008. The data represented clients from seven counties, which made up 48.5% of the California population. Fixed-effects logistic regression was used and included a continuous measure of time, in quarters, in the full-service partnership program; separate quarter indicators; and quarter-county interaction terms. The model thus controlled for both time-invariant personal characteristics (including personality as well as psychiatric and medical history as of entry into the study) and all time-varying county-level characteristics. RESULTS: Relative to persons receiving usual care, the odds of full-service partnership participants visiting the emergency department were 54% less after four quarters of treatment and 68% less after six quarters. CONCLUSIONS: The full-service partnership program was highly effective in reducing emergency visits. A statewide cost-effectiveness study should be conducted to determine the economic viability of the program.