Making the cut: Depression screening in urban general hospital clinics for culturally diverse Latino populations.

OBJECTIVES: We examined whether the cut-point 10 for the Patient Health Questionnaire-9 (PHQ9) depression screen used in primary care populations is equally valid for Mexicans (M), Ecuadorians (E), Puerto Ricans (PR) and non-Hispanic whites (W) from inner-city hospital-based primary care clinics; and whether stressful life events elevate scores and the probability of major depressive disorder (MDD). METHODS: Over 18-months, a sample of persons from hospital clinics with a positive initial PHQ2 and a subsequent PHQ9 were administered a stressful life event questionnaire and a Structured Clinical Interview to establish an MDD diagnosis, with oversampling of those between 8 and 12: (n=261: 75 E, 71 M, 51 PR, 64 W). For analysis, the sample was weighted using chart review (n=368) to represent a typical clinic population. Receiver Operating Characteristics analysis selected cut-points maximizing sensitivity (Sn) plus specificity (Sp). RESULTS: The optimal cut-point for all groups was 13 with the corresponding Sn and Sp estimates for E=(Sn 73%, Sp 71%), M=(76%, 81%), PR=(81%, 63%) and W=(80%, 74%). Stressful life events impacted screen scores and MDD diagnosis. CONCLUSIONS: Elevating the PHQ9 cut-point for inner-city Latinos as well as whites is suggested to avoid high false positive rates leading to improper treatment with clinical and economic consequences.

Buprenorphine and methadone treatment for opioid dependence by income, ethnicity and race of neighborhoods in New York City.

BACKGROUND: Geographic and demographic variation in buprenorphine and methadone treatment use in U.S. cities has not been assessed. Identifying variance in opioid maintenance is essential to improving treatment access and equity. PURPOSE: To examine the differential uptake of buprenorphine treatment in comparison to methadone treatment between 2004 and 2013 in neighborhoods in New York City characterized by income, race and ethnicity. METHODS: Social area (SA) analysis of residential zip codes of methadone and buprenorphine patients in NYC, which aggregated zip codes into five social areas with similar percentages of residents below poverty, identifying as Black non-Hispanic and as Hispanic, to examine whether treatment rates differed significantly among social areas over time. For each rate, mixed model analyses of variance were run with fixed effects for social area, year and the interaction of social area by year. RESULTS: Buprenorphine treatment increased in all social areas over time with a significantly higher rate of increase in the social area with the highest income and the lowest percentage of Black, Hispanic, and low-income residents. Methadone treatment decreased slightly in all social areas until 2011 and then increased bringing rates back to 2004 levels. Treatment patterns varied by social area. CONCLUSIONS: Buprenorphine treatment rates are increasing in all social areas, with slower uptake in moderate income mixed ethnicity areas. Methadone rates have remained stable over time. Targeted investments to promote public sector buprenorphine prescription may be necessary to reduce disparities in buprenorphine treatment and to realize its potential as a public health measure.

Prevalence and Diagnosis Rates of Childhood ADHD Among Racial-Ethnic Groups in a Public Mental Health System.

OBJECTIVE: This study estimated the proportions of Hispanic and non-Hispanic white and black children ages three to 17 with a diagnosis of attention-deficit hyperactivity disorder (ADHD) receiving services from the New York State public mental health system (NYS PMHS) and their annual treated ADHD prevalence rates. Findings were compared with those of recent national studies of general population samples. METHODS: Data were from a 2011 survey of users of NYS PMHS nonresidential services. Adjusted odds ratios compared the probability of an ADHD diagnosis among the groups by age, gender, and insurance type. Prevalence rates were compared among groups by age and gender. RESULTS: An estimated 133,091 children used the NYS PMHS, of whom 31% had an ADHD diagnosis. The prevalence rate of ADHD among whites was significantly lower than that among Hispanics or blacks in all gender and age groups except Hispanic females ages 13 to 17. White children were significantly less likely than black children to receive an ADHD diagnosis. CONCLUSIONS: National studies have reported higher ADHD rates among white children. Compared with children in the NYS PMHS, those in national studies had multiple access points to care, including private psychiatrists and clinicians and primary care practitioners. The higher reported ADHD rates in national studies may reflect higher rates of private insurance among white children, which would increase the likelihood of their using private practitioners. Cultural factors that influence whether and where care is sought and whether practitioners appropriately diagnosis ADHD may also explain the difference in findings.

Exact distribution of a maximally selected Wilcoxon and a new hybrid test of symmetry.

Recently, a maximally selected normalized Wilcoxon, whose asymptotic distribution is a Brownian Bridge, was proposed for testing symmetry of a distribution about zero. The test sequentially discards observations whose absolute value is below increasing thresholds. The Wilcoxon is obtained at each threshold, and the maximum is the test statistic. We develop a recursive function for the exact distribution of a modification of the Max Wilcoxon test (MW) and provide critical values and a program for computing the p-value for a sample. A new hybrid test that combines the sign and MW tests is introduced. The power of MW and the new hybrid test are compared with Modarres and Gastwirth's hybrid test (MGH) and the Max McNemar (MM), under the generalized lambda distributions (GLD) family and two normal mixture models. The MW and the new hybrid test outperform the MGH, which is superior to the MM test in the GLD family. In one mixture model, MM is the least powerful test and the remaining three are essentially equivalent. In the second mixture model, when the zero median assumption is nearly valid, the MW test does well; its performance degrades when this assumption is violated. In the latter case, the MM performs better than MW for the same degree of skewness because the MM simultaneously tests both symmetry and zero median. Data from a genetic study of monozygotic twins discordant for major depressive disorder is used to illustrate the new tests.

Access to and use of non-inpatient services in New York State among racial-ethnic groups.

OBJECTIVE Nationwide studies contrasting service use of racial-ethnic groups provide an overview of disparities, but because of variation in populations and service systems, local studies are required to identify specific targets for remedial action. The authors report on the use of non-inpatient services regulated in New York State (NYS) and report use by the state's larger cultural groups. METHODS Data from the NYS Patient Characteristics Survey were used to estimate annual treated prevalence and treatment intensity, defined as the average number of annual weeks in service for non-Hispanic blacks, Hispanics, Asians, and non-Hispanic whites. The latter rates were obtained for specific types of treatment use, by person's age and diagnosis, for the state and for population density-defined regions. Statistical methods contrasted rates of whites with other groups. RESULTS A total of 578,496 individuals in these racial-ethnic groups were served in 2,500 programs, and 51% of those served were nonwhite. Treated prevalence rates of whites were lower than those of blacks and Hispanics and were substantially higher than prevalence rates for Asians. Statewide treatment intensity rates of all racial-ethnic and age groups were comparable except for lower use among Asians >65. Key findings from granular analyses were lower treatment intensity rates for black youths with disruptive disorders, Hispanic adults with anxiety disorders, and Asians >65 with depression compared with white counterparts. In upstate metropolitan areas, black youths and Hispanic adults received services in fewer weeks than whites, and in the New York City metropolitan area, whites >65 had higher treatment intensity rates than contrast groups. CONCLUSIONS Findings suggest a need for assistance to black families in negotiating the multiple systems used by their children, clinical training focusing on cultural symptom presentation, screening of Asians in community settings, and mandated cultural competency assessments for all programs.

A maximally selected test of symmetry about zero.

The problem of testing symmetry about zero has a long and rich history in the statistical literature. We introduce a new test that sequentially discards observations whose absolute value is below increasing thresholds defined by the data. McNemar's statistic is obtained at each threshold and the largest is used as the test statistic. We obtain the exact distribution of this maximally selected McNemar and provide tables of critical values and a program for computing p-values. Power is compared with the t-test, the Wilcoxon Signed Rank Test and the Sign Test. The new test, MM, is slightly less powerful than the t-test and Wilcoxon Signed Rank Test for symmetric normal distributions with nonzero medians and substantially more powerful than all three tests for asymmetric mixtures of normal random variables with or without zero medians. The motivation for this test derives from the need to appraise the safety profile of new medications. If pre and post safety measures are obtained, then under the null hypothesis, the variables are exchangeable and the distribution of their difference is symmetric about a zero median. Large pre-post differences are the major concern of a safety assessment. The discarded small observations are not particularly relevant to safety and can reduce power to detect important asymmetry. The new test was utilized on data from an on-road driving study performed to determine if a hypnotic, a drug used to promote sleep, has next day residual effects.

Racial differences in the availability and use of electroconvulsive therapy for recurrent major depression.

BACKGROUND: Black Americans with depression were less likely to receive electroconvulsive therapy (ECT) than whites during the 1970s and 80s. This pattern was commonly attributed to treatment of blacks in lower quality hospitals where ECT was unavailable. We investigated whether a racial difference in receiving ECT persists, and, if so, whether it arises from lesser ECT availability or from lesser ECT use within hospitals conducting the procedure. METHODS: Black or white inpatient stays for recurrent major depression from 1993 to 2007 (N=419,686) were drawn from an annual sample of US community hospital discharges. The marginal disparity ratio estimated adjusted racial differences in the probabilities of (1) admission to a hospital capable of conducting ECT (availability), and (2) ECT utilization if treated where ECT is conducted (use). RESULTS: Across all hospitals, the probability of receiving ECT for depressed white inpatients (7.0%) greatly exceeded that for blacks (2.0%). Probability of ECT availability was slightly greater for whites than blacks (62.0% versus 57.8%), while probability of use was markedly greater (11.8% versus 3.9%). The white versus black marginal disparity ratio for ECT availability was 1.07 (95% confidence interval 1.06-1.07) and stable over the period, while the ratio for use fell from 3.2 (3.1-3.4) to 2.5 (2.4-2.7). LIMITATIONS: Depressed persons treated in outpatient settings or receive no care are excluded from analyses. CONCLUSIONS: Depressed black inpatients continue to be far less likely than whites to receive ECT. The difference arises almost entirely from lesser use of ECT within hospitals where it is available.

The Nathan Kline Institute cultural competency assessment scale: psychometrics and implications for disparity reduction.

The NKI Cultural Competency Assessment Scale measures organizational CC in mental health outpatient settings. We describe its development and results of tests of its psychometric properties. When tested in 27 public mental health settings, factor analysis discerned three factors explaining 65% of the variance; each factor related to a stage of implementation of CC. Construct validity and inter-rater reliability were satisfactory. In tests of predictive validity, higher scores on items related to linguistic and service accommodations predicted a reduction in service disparities for engagement and retention outcomes for Hispanics. Disparities for Blacks essentially persisted independent of CC scores.

Estimating treated prevalence and service utilization rates: assessing disparities in mental health.

There is considerable public concern about health disparities among different cultural/racial/ethnic groups. Important process measures that might reflect inequities are treated prevalence and the service utilization rate in a defined period of time. We have previously described a method for estimating N, the distinct number who received service in a year, from a survey of service users at a single point in time. The estimator is based on the random variable 'time since last service', which enables the estimation of treated prevalence. We show that this same data can be used to estimate the service utilization rate, E(J), the mean number of services in the year. If the sample is typical with respect to the time since last visit, the MLE of E(J) is asymptotically unbiased. Confidence intervals and a global test of equality of treated prevalence and service utilization rates among several groups are given. A data set of outpatient mental health services from a county in New York State for which the true values of the parameters are known is analyzed as an illustration of the methods and an appraisal of their accuracy.

Randomized, double-blind, placebo-controlled trial of vigabatrin for the treatment of cocaine dependence in Mexican parolees.

OBJECTIVE: Cocaine dependence is associated with severe medical, psychiatric, and social morbidity, but no pharmacotherapy is approved for its treatment in the United States. The atypical antiepileptic vigabatrin (gamma-vinyl gamma-aminobutyric acid [GABA]) has shown promise in animal studies and open-label trials. The purpose of the present study was to assess the efficacy of vigabatrin for short-term cocaine abstinence in cocaine-dependent individuals. METHOD: Participants were treatment seeking parolees who were actively using cocaine and had a history of cocaine dependence. Subjects were randomly assigned to a fixed titration of vigabatrin (N=50) or placebo (N=53) in a 9-week double-blind trial and 4-week follow-up assessment. Cocaine use was determined by directly observed urine toxicology testing twice weekly. The primary endpoint was full abstinence for the last 3 weeks of the trial. RESULTS: Full end-of-trial abstinence was achieved in 14 vigabatrin-treated subjects (28.0%) versus four subjects in the placebo arm (7.5%). Twelve subjects in the vigabatrin group and two subjects in the placebo group maintained abstinence through the follow-up period. The retention rate was 62.0% in the vigabatrin arm versus 41.5% in the placebo arm. Among subjects who reported prestudy alcohol use, vigabatrin, relative to placebo, was associated with superior self-reported full end-of-trial abstinence from alcohol (43.5% versus 6.3%). There were no differences between the two groups in drug craving, depressed mood, anxiety, or Clinical Global Impression scores, and no group differences in adverse effects emerged. CONCLUSIONS: This first randomized, double-blind, placebo-controlled trial supports the safety and efficacy of short-term vigabatrin treatment of cocaine dependence.

Model-based multiplicity estimation of population size.

A survey is conducted at w of K selection units or lists, e.g. health care institutions or weeks in a year, to estimate N, the total number of individuals with particular characteristics. Our estimator utilizes two items determined for each survey participant: the number, u, among the w lists in S and the number, j, among all K lists on which each survey participant appears. In its traditional form, selection units are chosen using probability sampling and the statistical properties of the estimator derive from the sampling mechanism. Here, selection units are purposively chosen to maximize the chance that they are 'typical' and a model-based analysis is used for inference. If the sample is typical, the ML estimators of N and E(J) are unbiased. If a condition on the second moment of U/J is satisfied, the model-based variance of the estimator of N based on a purposively chosen typical sample is smaller than one based on a randomly chosen sample. Methods to test whether the typical assumption is valid using data from the survey are not yet available. The importance of proper selection of the sample to maximize the chance that it is typical and model breakdown does not occur must be emphasized.

Estimating numbers of unsheltered homeless people through plant-capture and postcount survey methods.

OBJECTIVES: We sought to increase the accuracy of New York City's estimates of its unsheltered homeless population. METHODS: We employed 2 approaches to increasing count accuracy: a plant-capture strategy in which embedded decoys (or "plants") were used to estimate the proportion of visible homeless people missed by enumerators and a postcount survey of service users designed to estimate the proportion of unsheltered homeless people who were not visible. RESULTS: Plants at 17 sites (29%) reported being missed in the count, because counters either did not visit those sites or did not interview the plants. Of 293 homeless service users who were not in shelters, 31% to 41% were in locations deemed not visible to counters. CONCLUSIONS: Both plant-capture estimation and postcount surveys are feasible approaches that can increase the accuracy of estimates of unsheltered homeless populations.

Coping with disasters: estimation of additional capacity of the mental health sector to meet extended service demands.

BACKGROUND: The September 11th disaster in New York City resulted in an increase in mental health service delivery as a vast network of providers responded to the urgent needs of those impacted by the tragedy. Estimates of current capacity, potential additional capacity to deliver services and of potential shortfall within the mental health sector are needed pieces of information for planning the responses to future disasters. AIMS OF THE STUDY: Using New York State data, to determine the distribution of clinical service delivery rates among programs and to examine an explanatory model of observed variation; to estimate potential additional capacity in the mental health sector; and to estimate shortfall based on this capacity and data from studies on the need and use of services post September 11th METHODS: Empirical distributions of weekly clinical service delivery rates in programs likely to be used by persons with post disaster mental health problems were obtained from available data. Three regression models were fit to explain rate variation in terms of unmodifiable program characteristics likely to impact the rates. We argue that rates could not be easily increased if any of the models had good explanatory power, and could be increased if it did not. All models had poor fit. We then assumed that the median and 75th percentile of the clinical service delivery rates were candidates for the minimum production capability of a clinician. The service rates of those clinicians whose rates fell below these quartiles were increased to the quartile value to yield estimates of potential additional capacity. These were used along with data on clinical need to estimate shortfall. RESULTS: There is substantial variation in clinical service delivery rates within impact regions and among programs serving different age populations. The estimate of the percent increase in services overall based on the median is 12% and based on the 75th percentile is 27%. Using an estimate of need of.03 suggested by available data, and a range of services (1-10) that might be required in a six month period, shortfall estimates based on the median ranged between 22-92% and for the 75th percentile from no shortfall to 86%. A less conservative estimate of need of.05 produces median shortfall ranging between 59-96% and for the 75th percentile between 10-91%. LIMITATIONS: While the program descriptor variables used in the explanatory model of rates were those most likely to impact rates, explanatory power of the model might have increased if other characteristics that are not modifiable had been included. In this case, the assumption that service production can be increased is called into question. IMPLICATIONS FOR HEALTH CARE PROVISION AND USE: In the first six months post September 11th, in New York State (NYS) 250,000 persons received crisis counseling through Project Liberty. In 1999, NYS served approximately that same number in mental health clinic programs during the entire year. The estimates of this study suggest that additional funding and personnel are needed to provide mental health services in the event of a major disaster. IMPLICATIONS FOR HEALTH POLICIES: A disaster plan is needed to coordinate the use of current and additional personnel including mental health resources from other sources and sectors.

Estimating population size and duplication rates when records cannot be linked.

The capture-recapture approach to estimating the size of a population is a well-studied area of statistics. The number of distinct individuals, N(A) and N(B), on each of two lists, A and B, and the number common to both lists, N(AB), are used to form an estimate of the binomial probability of being on one of the lists, which then allows an estimate to be made of the size of the population. Critical to the method is an accurate count of N(AB). We consider situations in which this count is not available. Such problems arise in a variety of behavioural health contexts in which the need for protection of privacy may prevent sharing identifying information, so it is not possible to specifically match an individual who appears on one list with an individual on the other. Suppose that the birth dates and/or other demographics of individuals on each list are known. We introduce two methods for estimating the duplication rates and the size of the population. Conditioning on the set beta of birth dates of those on list B, N(A) and N(B), the maximum likelihood estimators (MLEs) and their variance are derived. The MLEs are based on the proportion of individuals on list A whose birth dates fall in beta. This approach is particularly useful if list B itself contains duplicates. The second model utilizes the full sample distribution of the birth dates. We generalize this approach to accommodate multiple demographic characteristics. The approaches are applied to the problem of estimating duplication rates and the population size of veterans who have mental illness in Kings County, NY. The data are lists of those receiving service from the Veterans Administration system and from providers funded or certified by the New York State Office of Mental Health.

Statistical determination of cost-effectiveness frontier based on net health benefits.

Statistical methods are given for producing a cost-effectiveness frontier for an arbitrary number of programs. In the deterministic case, the net health benefit (NHB) decision rule is optimal; the rule funds the program with the largest positive NHB at each lambda, the amount a decision-maker is willing to pay for an additional unit of effectiveness. For bivariate normally distributed cost and effectiveness variables and a specified lambda, a statistical procedure is presented, based on the method of constrained multiple comparisons with the best (CMCB), for determining the program with the largest NHB. A one-tailed t test is used to determine if the NHB is positive. To obtain a statistical frontier in the lambda-NHB plane, we develop a method to produce the region in which each program has the largest NHB, by pivoting a CMCB confidence interval. A one-sided version of Fieller's theorem is used to determine the region where the NHB of each program is positive. At each lambda, the pointwise error rate is bounded by a prespecified alpha. Upper bounds on the familywise error rate, the probability of an error at any value of lambda, are given. The methods are applied to a hypothetical clinical trial of antipsychotic agents.

The familywise error rate of a simultaneous confidence band for the incremental net health benefit.

Interest in the use of net health benefit in cost-effectiveness analysis derives from its optimality property for decision-making. A description of the results of an economic evaluation of health care interventions is incomplete if it does not include point and interval estimates of this outcome measure. A simultaneous confidence band for the incremental net health benefit, INHB(lambda), for all lambda may be obtained by forming a confidence interval based on student's t statistic, and letting the willingness-to-pay value, lambda, run over all values. The familywise error rate (FWER) of the simultaneous confidence band is the probability that the confidence interval does not cover the true INHB(lambda) for some value of lambda. We show that the FWER equals P(T(2)>t(2)), where T(2) follows Hotelling's central distribution and that the simultaneous confidence band does not cover the true INHB(lambda) if and only if a T(2) based confidence ellipsoid does not cover the true mean c-e vector.

Cost-Shifting from Private to Public Payers: The Scene Before Parity Legislation.

BACKGROUND: Analyses that have been conducted previously on the implications of parity have focused on the concern that mental health costs of private payers will substantially increase. A complete analysis of the cost implications of parity, however, also needs to consider whether the mental health costs of public payers may increase particularly if employers or private insurers attempt to extrude enrollees with severe mental illness. This study examines the extent of mental health cost shifting from private to public payers during two separate two-year periods prior to the implementation of parity legislation. The results of the analyses can serve as a necessary baseline against which the consequences of parity legislation on this direction of cost-shifting can be examined. METHODS: The study utilizes an all payer data set that contains information on the use of specialty mental health services (excluding private practitioners) by adults in an urban and a rural county in New York State. For each year of two time periods -1991/1992 and 1995/ 1996 - consumers were classified into payer groups based on whether their services were paid for by "Private Only", "Public Only", "Private/Public", "Self Pay" or "Other" payers. The proportion of individuals who moved from one payer group to another from one year to the following year of each time period and the average yearly costs under these payers were examined. Logistic regression models were used to identify the characteristics of persons most likely to remain with Private Only Payers in contrast to those likely to shift to Private/Public Only payers or to Public Only Payers. RESULTS: In both two-year time periods, the percent of persons who shifted in one year from Private Only to either Private/Public or Public Only payers was small. In contrast, a person in the Private/Public group has more than a 12 percent likelihood of shifting to a Public Only payer in the subsequent year. The average annual costs of the Private/Public group were higher than that of any other payer group. The average annual costs of persons who shifted into the Private/Public group from any other payer group or remained there from the previous year were even higher. The logistic regression analyses for both time periods showed that persons who shifted from Private Only to Private/Public or Public Only payers in contrast to those who remained with Private Only payers were more likely to have subsidized incomes, be younger and have a mental health disability. In 1995, the likelihood of the shift was also increased for those who were nonwhite and/or had a substance abuse disability. IMPLICATIONS: This study has found that individuals rarely shift directly from private payers to public payers. Rather, they first shift to having services reimbursed by both private and public payers, and during this period their average total service costs are extremely high. Persons who shift from private payers to having at least some of their services paid by public payers in subsequent years appear to be either young employees or young dependents who have severe mental illness or mental illness disabilities. Abusing substances and/or being nonwhite also increase the likelihood of a shift to public payers. Along with parity mandates, there has been an increase in managed care controls. The extent to which these controls will be used to accelerate the movement of these high cost persons from private to public payers needs close watch.