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At least 109 records · Page 6Linked to original sources
PubMed2003

Effectiveness and cost-effectiveness of four treatment modalities for substance disorders: a propensity score analysis.

OBJECTIVE: To assess the effectiveness and cost-effectiveness of four treatment modalities for substance abuse. DATA SOURCES: The study used data from the Services Research Outcomes Study (SROS), a survey of 3,047 clients in a random sample of 99 drug treatment facilities across the United States. Detailed sociodemographic, substance use, and clinical data were abstracted from treatment records. Substance abuse outcome and treatment history following discharge from index facilities were assessed using a comprehensive interview with 1,799 of these individuals five years after discharge. Treatment success was defined in two ways: as abstinence and as any reduction in substance use. STUDY DESIGN: Effectiveness and cost-effectiveness of four modalities were compared: inpatient, residential, outpatient detox/methadone, and outpatient drug-free. Clients were stratified based on propensity scores and analyses were conducted within these strata. Sensitivity analyses examined the impact of future substance abuse treatment on effectiveness and cost-effectiveness estimates. PRINCIPAL FINDINGS: Treatment of substance disorders appears to be cost-effective compared to other health interventions. The cost per successfully treated abstinent case in the least costly modality, the outpatient drug-free programs, was 6,300 dollars (95 percent confidence intervals: 5,200-7,900 dollars) in 1990 dollars. There were only minor differences between various modalities of treatment with regard to effectiveness. However, modalities varied considerably with regard to cost-effectiveness. Outpatient drug-free programs were the most cost-effective. There was little evidence that relative effectiveness or cost-effectiveness of programs varied according to factors that were associated with selection into different programs. CONCLUSIONS: Substance disorders can be treated most cost-effectively in outpatient drug-free settings. Savings from transitioning to the most cost-effective treatment modality may free resources that could be reinvested to improve access to substance abuse treatment for a larger number of individuals in need of such treatment.

Adult↗
PubMed2006

A propensity score analysis of brief worksite crisis interventions after the World Trade Center disaster: implications for intervention and research.

BACKGROUND: Postdisaster crisis interventions have been viewed by some as appropriate to enhance the mental health status of persons affected by large-scale traumatic events. However, studies and systematic reviews have challenged the effectiveness of these efforts. OBJECTIVES: The focus of this study was to examine the impact of brief mental health interventions received by employees at the worksite after the World Trade Center disaster (WTCD) among workers in New York City (NYC). RESEARCH DESIGN: The data for the present study come from a prospective cohort study of 1121 employed adults interviewed by telephone in a household survey 1 year and 2 years after the WTCD. All study participants were living in NYC at the time of the attacks. For the current study, we used propensity scores to match intervention cases (n = 150) to nonintervention controls (n = 971) using a 1:5 matching ratio based on a bias-corrected nearest-neighbor algorithm. RESULTS: Approximately 7% of NYC adults (approximately 425,000 persons) reported receiving employer-sponsored, worksite crisis interventions related to the WTCD provided by mental health professionals. In addition, analyses indicated that attending 1 to 3 brief worksite sessions was associated with positive outcomes up to 2 years after the WTCD across a spectrum of results, including reduced alcohol dependence, binge drinking, depression, PTSD severity, and reduced anxiety symptoms. CONCLUSIONS: Although our study had limitations, it is one of the few to suggest that brief postdisaster crisis interventions may be effective for employees after mass exposure to psychologically traumatic events. The reasons for the effectiveness of these interventions are unclear at this time and warrant further investigation.

Adult↗
PubMed2005

Hypertrophic obstructive cardiomyopathy: comparison of outcomes after myectomy or alcohol ablation adjusted by propensity score.

OBJECTIVE: In November 1998, our center began offering alcohol ablation as an alternative to surgical myectomy for patients with hypertrophic obstructive cardiomyopathy. Patients with concomitant lesions were referred for surgical intervention, and the others were offered either treatment option. We sought to review the early outcomes for both protocols. METHODS: One hundred fifty patients had intervention for hypertrophic obstructive cardiomyopathy to June 30, 2003. Sixty patients elected to have alcohol ablation, and 5 crossed over to surgical intervention. A total of 95 patients had a myectomy. Patients having an isolated myectomy (n = 48) are compared with those who had an ablation. Hospital records were reviewed, and follow-up contact (mean, 2.2 years) with the patient or referring cardiologist and recent echocardiographic reports were obtained. Differences in clinical and hemodynamic outcomes between achieved treatment groups were compared after adjustment for differing baseline patient characteristics, including use of a propensity score, to adjust for the non-randomization. RESULTS: The patients undergoing alcohol ablation (n = 60) were older (58 vs 48 years) and had fewer associated lesions (1 vs 39 patients), lower pressure gradients (67 vs 73 mm Hg), and similar symptomatic status and degrees of mitral regurgitation compared with those in the myectomy group. Alcohol ablation was abandoned in 6 patients, 5 of whom underwent myectomy. Among the completed alcohol ablations, there were 5 late deaths, and 1 other patient was referred for myectomy. One late death occurred after myectomy. At latest follow-up, 3-year survival is 97%, and 92% of the patients are in New York Heart Association class II or I. Adjusted comparisons showed significantly lower postintervention left ventricular outflow gradients at rest in the myectomy group (5 vs 15 mm Hg), with provocation (14 vs 42 mm Hg), mitral systolic anterior motion (67% vs 29%), and New York Heart Association class. No significant difference was present in postintervention septal thickness or freedom from postintervention pacing, although in time-related analysis, the 3-year freedom from pacing is 88% versus 59% (P = .02), favoring myectomy. CONCLUSION: Either alcohol ablation or myectomy offers substantial clinical improvement for patients with hypertrophic obstructive cardiomyopathy. Hemodynamic resolution of the obstruction and its sequelae is more complete with myectomy. Residual lesions after alcohol ablation might affect longer-term outcomes.

Adult↗
PubMed1997

Estimating causal effects from large data sets using propensity scores.

The aim of many analyses of large databases is to draw causal inferences about the effects of actions, treatments, or interventions. Examples include the effects of various options available to a physician for treating a particular patient, the relative efficacies of various health care providers, and the consequences of implementing a new national health care policy. A complication of using large databases to achieve such aims is that their data are almost always observational rather than experimental. That is, the data in most large data sets are not based on the results of carefully conducted randomized clinical trials, but rather represent data collected through the observation of systems as they operate in normal practice without any interventions implemented by randomized assignment rules. Such data are relatively inexpensive to obtain, however, and often do represent the spectrum of medical practice better than the settings of randomized experiments. Consequently, it is sensible to try to estimate the effects of treatments from such large data sets, even if only to help design a new randomized experiment or shed light on the generalizability of results from existing randomized experiments. However, standard methods of analysis using available statistical software (such as linear or logistic regression) can be deceptive for these objectives because they provide no warnings about their propriety. Propensity score methods are more reliable tools for addressing such objectives because the assumptions needed to make their answers appropriate are more assessable and transparent to the investigator.

Breast Neoplasms↗
PubMed2006

Root replacement using stentless valves in the small aortic root: a propensity score analysis.

BACKGROUND: Root replacement using a stentless bioprosthesis may be the optimal approach to avoid patient-prosthesis mismatch in patients with a small aortic root. Primary root replacement, however, is considered to be associated with increased surgical risk. We compared early outcome of full root replacement with a stentless bioprosthesis with that of aortic valve replacement with a stented bioprosthesis using propensity score-matching analysis. METHODS: Of 231 patients undergoing elective, first-time aortic valve replacement with a small root (< or = 22 mm), 120 patients were selected using propensity score-matching analysis. They underwent either root replacement using a 23-mm stentless bioprosthesis (stentless group, n = 60) or supra-annular aortic valve replacement using a 21-mm stented bioprosthesis (stented group, n = 60). Preoperative characteristics and frequency of concomitant operations were identical. RESULTS: Duration of operation (196 +/- 54 versus 174 +/- 49 minutes), cardiopulmonary bypass (112 +/- 36 versus 91 +/- 33 minutes), and aortic cross-clamping (76 +/- 21 versus 61 +/- 21 minutes) were significantly longer in the stentless group. However, the need for perioperative transfusion and the incidence of postoperative reexploration for bleeding (3% versus 8%) was lower, and ventilation time was shorter. Mean duration of intensive care and hospital stay were also significantly shorter (2.3 +/- 1.7 versus 4.0 +/- 3.9 days, 8.9 +/- 3.1 versus 12.4 +/- 5.7 days). In-hospital mortality was identical (5% each). No independent predictor for in-hospital mortality was identified. CONCLUSIONS: Full root replacement using a stentless bioprosthesis does not increase postoperative morbidity or mortality of aortic valve replacement and may be advantageous in patients with a small aortic root.

Aged↗
PubMed2006

Substance abuse treatment and the recurrence of maltreatment among caregivers with children living at home: a propensity score analysis.

Policy and programmatic initiatives of the last decade have focused on increased coordination of services and expansion of prompt substance abuse treatment for mothers initially involved with child welfare services (CWS). Yet, little evidence has been amassed concerning the implications of this approach on the recurrent need for CWS. Data are from a large national probability sample of children and their caregivers involved with CWS following an allegation of maltreatment. Data include the recurrence of maltreatment reports for this group of children who remain at home. Selected from 1,101 caregivers with an indicated substance abuse problem, a group of 224 clients who did not receive services were compared with 224 treated clients. Event history analyses showed that clients who received substance abuse treatment were nearly twice as likely to have another child abuse report within 18 months. Reasons why participation in substance abuse treatment may result in greater involvement with CWS are posited.

Adolescent↗
PubMed2001

Utilizing propensity scores to estimate causal treatment effects with censored time-lagged data.

Observational studies frequently are conducted to compare long-term effects of treatments. Without randomization, patients receiving one treatment are not guaranteed to be prognostically comparable to those receiving another treatment. Furthermore, the response of interest may be right-censored because of incomplete follow-up. Statistical methods that do not account for censoring and confounding may lead to biased estimates. This article presents a method for estimating treatment effects in nonrandomized studies with right-censored responses. We review the assumptions required to estimate average causal effects and derive an estimator for comparing two treatments by applying inverse weights to the complete cases. The weights are determined according to the estimated probability of receiving treatment conditional on covariates and the estimated treatment-specific censoring distribution. By utilizing martingale representations, the estimator is shown to be asymptotically normal and an estimator for the asymptotic variance is derived. Simulation results are presented to evaluate the properties of the estimator. These methods are applied to an observational data set of acute coronary syndrome patients from Duke University Medical Center to estimate the effect of a treatment strategy on the mean 5-year medical cost.

Analysis of Variance↗
PubMed2007

The comparative effectiveness of anti-TNF therapy and methotrexate in patients with psoriatic arthritis: 6 month results from a longitudinal, observational, multicentre study.

OBJECTIVES: To compare the response to treatment with tumour necrosis factor (TNF) inhibitors and methotrexate (MTX) monotherapy in patients with psoriatic arthritis (PsA) within a real-life clinical setting. METHODS: We analysed data from an ongoing longitudinal, observational multicentre study in Norway. Our data comprised 526 cases of patients with PsA who received either anti-TNF treatment (n = 146) or MTX monotherapy (n = 380) and were followed for at least 6 months with measures of disease activity, health status and utility scores. A propensity score was computed to adjust for channelling bias. The changes in measures of disease activity and health-related quality of life from baseline to 3- and 6-month follow-up were compared between the groups with adjustments for the baseline value of the dependent variable and the propensity score (analyses of covariance (ANCOVA)). RESULTS: The groups were significantly different at baseline with respect to demographic and disease activity measures. The variables included in the propensity score were age, sex, number of previous disease modifying anti-rheumatic drugs (DMARDs), presence of erosive disease, treatment centre and investigator's global assessment. The adjusted changes at 6 months were significantly larger in the anti-TNF group for ESR, DAS-28, M-HAQ, patient's assessments of pain, fatigue and global disease activity on a visual analogue scale (VAS) and 4 out of 8 SF-36 dimensions. CONCLUSIONS: Clinical improvement was superior with TNF inhibitors compared to MTX monotherapy in patients with PsA, when assessed in this setting of daily clinical practice.

Adalimumab↗
PubMed2000

Can mentoring or skill training reduce recidivism? Observational study with propensity analysis.

We compared juvenile offenders' recidivism following nonrandom assignment to juvenile diversion (JD, n = 137), JD plus skill training (ST, n = 55), or JD plus mentoring (MEN, n = 45). Intake characteristics that distinguished intervention groups were used to calculate assignment propensity scores. After propensity score blocking balanced intake characteristics, ST proved more cost effective than MEN, achieving a 14% relative reduction in recidivism at a savings of $33,600 per hundred youths. In ST, 37% were rearrested 2 years or more after intake, compared to 51% in MEN and 46% in JD. In two of five propensity subclasses, time to first rearrest was longer in ST (M = 767 days) than in MEN (M = 638 days) or JD (M = 619 days). These results argue for an experimental comparison of ST and MEN and for observational studies with propensity analysis when randomization to juvenile justice interventions is infeasible.

Adolescent↗
PubMed2004

Does hospitalization impact survival after lower respiratory infection in nursing home residents?

BACKGROUND: Lower respiratory infection (LRI) is the leading cause of hospitalization for nursing home residents, but hospitalization is costly and may cause complications. OBJECTIVE: We sought to compare mortality and cost between episodes of LRI initially treated in the hospital versus the nursing home after controlling for illness severity and the probability of hospitalization. DESIGN: This was a prospective cohort study of nursing home residents with LRIs. SUBJECTS: We identified 1406 episodes of LRI in 36 nursing homes in central Missouri and the St. Louis area between August 15, 1995, and September 30, 1998. Economic analysis was restricted to 1033 episodes identified after March 31, 1997. MEASURES: We adjusted for the higher probability of initial hospitalization in sicker residents using measures of illness severity and a hospitalization propensity score. The propensity score was derived from a logistic regression model that included patient, physician, and facility variables. Estimated costs were attributed to initial treatment setting. RESULTS: After controlling for the probability of hospitalization and illness severity, hospitalization was not a significant mortality predictor (odds ratio 0.89, 95% confidence interval 0.52-1.52). Mean daily cost was $138.24 for initial nursing home treatment and $419.75 for the hospital. CONCLUSIONS: After controlling for illness severity and propensity for hospitalization, hospital treatment is not associated with either increased or decreased risk for mortality for nursing home residents with LRIs. For residents with low and medium mortality risk, nursing home treatment is likely to be safe and less costly.

Aged↗