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PubMed2026

Robust replication of associations across patient-mediated and provider-sourced EHR data in the All of Us research program.

The All of Us Research Program is assembling a nationwide cohort with electronic health record (EHR) resources through two complementary pathways: healthcare provider organization (HPO)-sourced EHRs and patient-mediated EHR (PME) contributed through patient portal linkages. The comparative research utility of these two data sources has not been systematically evaluated. Here, we compared PME and HPO EHRs with respect to disease prevalence, phenotype-phenotype associations, and replication of established genotype-phenotype associations using data from 19,703 PME and 373,887 HPO participants. We benchmarked disease prevalence against national estimates, conducted phenome-wide association studies for 10 commonly studied diseases, and tested replication of more than 5000 established genotype-phenotype associations across multiple ancestral groups. Disease prevalence was consistently lower in PME than in HPO, although prevalence of most diseases in both cohorts exceeded national estimates. Both data sources reproduced known phenotype-phenotype associations and showed moderate-to-strong concordance in effect sizes across the phenome. The overall genotype-phenotype replication rate was 49.1% (5399/10,999) in HPO and 5.9% (381/6482) in PME across ancestral groups, with effect sizes strongly correlated among well-powered associations (R = 0.84, P < 0.001). To disentangle the impact of sample size from data quality, we performed 1:1 propensity score matching. After matching, the replication gap in genotype-phenotype associations narrowed from 8.3-fold to 1.3-fold, with equivalent replication rates among adequately powered associations and strongly concordant effect sizes; comorbidity patterns were also consistent across all 10 diseases tested. These findings demonstrate that both data sources are valuable for clinical and genomic research and can inform other cohorts integrating provider-derived and patient-mediated EHRs.

Computational biology and bioinformatics↗

PubMed2003

Effects of outcome-driven insurance reimbursement on short-term weight control.

CONTEXT: Although most health insurers exclude coverage of weight control therapy, one local insurer offered partial reimbursement of the cost of a weight control program, using an incentive plan. OBJECTIVE: To determine whether outcome-driven insurer-based reimbursement improves participation in a weight control program and short-term weight loss outcomes. DESIGN: Cohort follow-up study between January 1998 and February 2001. SETTING: Community weight management program operated by an academic medical center. SUBJECTS: Obese participants who had the potential for reimbursement (Group A, n=25) and participants in the same program classes (Group B, n=100) who had no possibility for reimbursement. Subjects in Group B were selected from among 206 potential participants using a propensity score to match them with subjects in Group A on age, gender, ethnicity, starting BMI, starting weight, and educational, economic, and demographic variables. INTERVENTION: Group lifestyle-based weight management program. The insurer reimbursed half the cost of the program to obese participants who met minimum weight criteria, paid the program fee at enrollment, attended > or =10 of the 12 classes, and lost > or =6% of initial body weight after 12 weeks. MAIN OUTCOME MEASURES: Participation rates and weight loss outcomes. RESULTS: Group A subjects attended significantly more classes (mean+/-s.d.: 10.1+/-1.8 vs 8.2+/-2.5, P<0.001) and lost more weight than Group B subjects (6.1+/-3.1 vs 3.7+/-3.6%, P=0.002). While 84% of Group A subjects attended > or =10 classes, only 37% of Group B subjects did so (P<0.001); 56% of Group A subjects lost > or =6% of body weight, but only 20% of Group B subjects did so (P<0.001); 56% of Group A subjects achieved both the class attendance and weight loss goals, but only 14% of Group B subjects did so (P<0.001). Logistic regression estimated that Group A subjects had 8.2 times the odds of attending > or =10 classes and 4.5 times the odds of losing > or =6% of body weight of Group B subjects, after controlling for class attendance. CONCLUSIONS: Insurer-based reimbursement that is contingent upon initial financial commitment on the part of the patient, consistent program participation, and successful weight loss is associated with significantly better short-term weight control outcomes.

Adult↗

PubMed2002

Comparison of resource utilization by patients treated with transdermal fentanyl and long-acting oral opioids for nonmalignant pain.

OBJECTIVE: To quantify resource utilization and costs incurred for patients who received transdermal fentanyl as their first long-acting analgesic for non-malignant pain, and to compare these with utilization and costs for similar patients dispensed other long-acting oral opioids. DESIGN: A retrospective matched cohort study using medical claims data from a large New England Insurer. PATIENTS: We identified 478 patients without cancer who received transdermal fentanyl during 1995-1998. We selected patients who had no previous long-acting opioid dispensings and were enrolled during the 180 days before and 30 days following the initial dispensing. We used propensity scores to identify a matched comparison group of 478 long-acting oral opioid users. RESULTS: Transdermal fentanyl and matched long-acting oral opioid users incurred identical median costs for outpatient medical services and prescriptions during 2 years of follow-up. A larger proportion of transdermal fentanyl patients were still taking their initial opioid analgesic at the end of the 2-year follow-up than were patients initially taking other long-acting opioids. Use of short-acting opioids tapered off more slowly among transdermal fentanyl patients than among long-acting opioid patients. In the first 6 months, the transdermal fentanyl patients had more hospital discharges than the long-acting oral opioid patients, but this difference appeared to reflect preexisting conditions. CONCLUSIONS: Users of fentanyl transdermal system and other long-acting opioids experienced essentially identical evolution of health services utilization and costs over a 2-year period. The choice of long-acting opioid analgesia does not appear to be a determinant of future medical costs.

Journal Article↗

PubMed2006

Immune modulation using mistletoe (Viscum album L.) extracts Iscador.

One repeatedly finds that mistletoe (Viscum album L.) extracts show immune-modulating effects. This is also true in many cases in the experimental setting. Many of the experimental trials cannot, however, be transferred to the clinical situation - or only in a limited way. The aim of this work was to pursue the question of the extent to which the function of immune-competent cells can be influenced by mistletoe extracts. To do this, 3 clinical studies were carried out. Results from the first two studies will be presented here. In a prospective observational study with defined inclusion and exclusion criteria, the impact of two different doses of Iscador M (Malus) or Iscador Qu (Quercus) on the function and number of T-lymphocytes from tumor patients was studied. The immunological tests took place monthly during the first six months. Thirty-one patients were included in the slow dose group and 36 patients in the group with swift dose escalation. It was postulated that too swift increase in dosage would lead to stronger local reactions and impairment of the stimulation capacity of T-cells taken ex vivo and incubated for 72 h. The evaluation showed that patients with stronger local reactions at the injection site have an impairment of mitogen-induced stimulation capacity of T-cells. However, patients with stronger local reaction showed a significant decrease of HLA-DR+ T cells as compared to patients In a GCP-conform, controlled bicentric phase II study the aim was to investigate the efficacy of a perioperative intravenous mistletoe extract application on the modulation of operation-induced immune suppression. For this purpose 105 patients with breast cancer were recruited. At the treatment centre the patients received an infusion of 1 mg Iscador M Spezial prior to the start of an operation, in addition to normal medication, while this was not practised at the control centre. The primary trial objective was the oxidative burst in granulocytes taken from patients ex vivo prior to surgery, and 1 and 3 days after. In order to take account of possible differences in the two groups, propensity scores were used as the basis for a matched pair analysis. It became clear that inhibition of the granulocyte function in the treatment group was significantly less marked (p < 0.001; Wilcoxon). Mistletoe extract-related adverse reactions were not observed. Thus this special form of application could minimise the immune suppression triggered by anaesthesia and operation stress.

Animals↗

PubMed2005

[Efficacy and safety of a herbal drug containing hawthorn berries and D-camphor in hypotension and orthostatic circulatory disorders/results of a retrospective epidemiologic cohort study].

BACKGROUND AND OBJECTIVE: Korodin Herz-Kreislauf-Tropfen, a herbal drug containing D-camphor (CAS 76-22-2; 2.5 %) and a liquid extract of fresh hawthorn berries (97.3%), has been used since many years for the treatment of orthostatic hypotension. The combination as well as its constituents were tested in clinical trials against placebo with healthy volunteers and patients using tilt-tests. The objective of this study was to investigate efficacy and safety of the drug under the conditions of medical practice in comparison to other drugs admitted for this indication. PATIENTS AND METHODS: The study was performed as an epidemiological retrospective cohort study in 46 medical practices in Germany. In the practices the files were reviewed for patients who were treated between 1st January 2000 and 31st December 2002 for orthostatic hypotension. Included in the study were all patients who were treated either with the test drug or a control drug containing etilefrine, oxilofrine, midodrine, norfenefrine or dihydroergotamine and who met the inclusion criteria. The data of the files were coded, transferred to case report forms and augmented by the physician's statements about symptoms and success. Effect criteria were the improvement of symptoms and change of blood pressure during treatment. The correctness of the data was controlled using anonymous copies of the files. A total of 490 patients (399 in the test-group and 91 in the control group) between 11 and 102 years were included in the study. To correct heterogeneities in baseline conditions, treatment results were adjusted by regression and stratification to equal baseline conditions using the propensity score. RESULTS: The adjusted odds ratio for improvement was 5.6, the adjusted mean increase of the systolic blood pressure the 2-fold compared to the control group. The difference was highly significant and did not depend on age or initial blood pressure. In the test group two adverse events were observed which had no relation to the medication; in the control group one reversible event with a probable relation to the medication was observed. CONCLUSIONS: The test drug was proven as effective and safe in the treatment of orthostatic hypotension in medical practice for all age groups and independent of the initial blood pressures.

Adult↗

PubMed2004

[The impact of antipsychotic medication on the incidence and the costs of inpatient treatment in people with schizophrenia: results from a prospective observational study].

SUBJECT: Subject of the study is the analysis of the impact of antipsychotic medication on the incidence and the costs of inpatient treatment in patients with schizophrenia. METHODS: In a prospective longitudinal study with 5 points of measurement incidence and the costs of inpatient treatment, the type of antipsychotic medication, as well as the clinical and social characteristics of 307 outpatients with the diagnosis of schizophrenia (ICD 10 F 20.0) were assessed over a period of 2.5 years. The impact of antipsychotic medication on the incidence of inpatient treatment was analysed by means of a random-effect logit model. The impact of antipsychotic medication on the costs of inpatient treatment was analysed by means of a random-effect tobit model. Selection effects were controlled by means of propensity scores. RESULTS: Patients who received antipsychotic treatment with conventional, new atypical or depot neuroleptics had a lower incidence of inpatient treatment and caused lower costs in comparison to patients without antipsychotic treatment. The same effect was found for patients who received a combined treatment with conventional and depot neuroleptics. No effects were found for clozapine or for a combination treatment with conventional and atypical neuroleptics. No significant differences between the effects of conventional, new atypical or depot-neuroleptics were found. CONCLUSION: The application of neuroleptic medication in schizophrenia treatment generally reduces the incidence and the costs of inpatient treatment. An extension of the use of clozapine or new atypical neuroleptics to all patients with schizophrenia will not generally improve the treatment effectiveness regarding to the incidence and the costs of inpatient treatment.

Adult↗

PubMed2004

[Methodolocical issues of naturalistic observational studies on the economic evaluation of neuroleptic treatment for schizophrenic disease].

Methodological problems of prospective natural trials are discussed. The application of adequate methods is demonstrated by analysing the effects of antipsychotic medical treatment on the probability and the costs of inpatient episodes of 307 patients with schizophrenia for 2.5 years. Selection bias is controlled by the propensity score method. Effects of medical treatment on the incidence of inpatient episodes are analysed by means of a random-effect logit model. Effects of medical treatment on the costs of inpatient episodes are analysed by means of a random-effect Tobit model. Results of the study show that antipsychotic medical treatment reduces the probability and the costs of inpatient treatment irrespective of the type of neuroleptic drugs. The hypothesis of a higher effectivity of atypical neuroleptics in comparison to conventional antipsychotics regarding the reduction of the incidence and the costs of inpatient treatment was not supported. Beyond the effects of medical treatment the study results indicate that improving social support and competence for coping with life events as well as providing community mental health services may reduce the risk and the costs of inpatient episodes.

Adolescent↗

PubMed2005

Antenatal glucocorticoid treatment decreases mortality and chronic lung disease in survivors among 23- to 28-week gestational age preterm infants.

The purpose of this study was to analyze the influence of antenatal glucocorticoid therapy (AGT) on mortality and chronic lung disease (CLD) in surviving preterm infants 23 to 28 weeks gestational age (WGA). This was a multicenter, prospective, observational study. A total of 2448 infants 23 to 28 WGA were born in 2002 to 2003; 27.7% did not receive AGT, 18.8% were exposed to partial AGT, and 53.5% were exposed to complete AGT. A total of 883 died and 22.9% of 1537 survivors were affected by CLD. Unadjusted univariate analysis showed AGT was associated with a reduction in mortality (p<0.001), either with partial or complete AGT courses, and also with a reduction in CLD in survivors (p<0.001), but only with complete AGT courses. In logistic regression analysis adjusted for confounding factors and a propensity score for AGT, AGT was significant and independently associated with a reduction of mortality, but only for complete AGT course (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.47 to 0.87; p=0.004), and with a decrease in CLD if a complete AGT course was administered (OR, 0.63; 95% CI, 0.45 to 0.89; p=0.009). A complete course of AGT in 23 to 28 WGA pregnancies is associated with decreased rates of neonatal mortality and CLD disease in surviving infants.

Bronchopulmonary Dysplasia↗

PubMed2005

Perioperative beta-blocker therapy and mortality after major noncardiac surgery.

BACKGROUND: Despite limited evidence from randomized trials, perioperative treatment with beta-blockers is now widely advocated. We assessed the use of perioperative beta-blockers and their association with in-hospital mortality in routine clinical practice. METHODS: We conducted a retrospective cohort study of patients 18 years of age or older who underwent major noncardiac surgery in 2000 and 2001 at 329 hospitals throughout the United States. We used propensity-score matching to adjust for differences between patients who received perioperative beta-blockers and those who did not receive such therapy and compared in-hospital mortality using multivariable logistic modeling. RESULTS: Of 782,969 patients, 663,635 (85 percent) had no recorded contraindications to beta-blockers, 122,338 of whom (18 percent) received such treatment during the first two hospital days, including 14 percent of patients with a Revised Cardiac Risk Index (RCRI) score of 0 and 44 percent with a score of 4 or higher. The relationship between perioperative beta-blocker treatment and the risk of death varied directly with cardiac risk; among the 580,665 patients with an RCRI score of 0 or 1, treatment was associated with no benefit and possible harm, whereas among the patients with an RCRI score of 2, 3, or 4 or more, the adjusted odds ratios for death in the hospital were 0.88 (95 percent confidence interval, 0.80 to 0.98), 0.71 (95 percent confidence interval, 0.63 to 0.80), and 0.58 (95 percent confidence interval, 0.50 to 0.67), respectively. CONCLUSIONS: Perioperative beta-blocker therapy is associated with a reduced risk of in-hospital death among high-risk, but not low-risk, patients undergoing major noncardiac surgery. Patient safety may be enhanced by increasing the use of beta-blockers in high-risk patients.

Adrenergic beta-Antagonists↗

PubMed2006

The risk associated with aprotinin in cardiac surgery.

BACKGROUND: The majority of patients undergoing surgical treatment for ST-elevation myocardial infarction receive antifibrinolytic therapy to limit blood loss. This approach appears counterintuitive to the accepted medical treatment of the same condition--namely, fibrinolysis to limit thrombosis. Despite this concern, no independent, large-scale safety assessment has been undertaken. METHODS: In this observational study involving 4374 patients undergoing revascularization, we prospectively assessed three agents (aprotinin [1295 patients], aminocaproic acid [883], and tranexamic acid [822]) as compared with no agent (1374 patients) with regard to serious outcomes by propensity and multivariable methods. (Although aprotinin is a serine protease inhibitor, here we use the term antifibrinolytic therapy to include all three agents.) RESULTS: In propensity-adjusted, multivariable logistic regression (C-index, 0.72), use of aprotinin was associated with a doubling in the risk of renal failure requiring dialysis among patients undergoing complex coronary-artery surgery (odds ratio, 2.59; 95 percent confidence interval, 1.36 to 4.95) or primary surgery (odds ratio, 2.34; 95 percent confidence interval, 1.27 to 4.31). Similarly, use of aprotinin in the latter group was associated with a 55 percent increase in the risk of myocardial infarction or heart failure (P<0.001) and a 181 percent increase in the risk of stroke or encephalopathy (P=0.001). Neither aminocaproic acid nor tranexamic acid was associated with an increased risk of renal, cardiac, or cerebral events. Adjustment according to propensity score for the use of any one of the three agents as compared with no agent yielded nearly identical findings. All the agents reduced blood loss. CONCLUSIONS: The association between aprotinin and serious end-organ damage indicates that continued use is not prudent. In contrast, the less expensive generic medications aminocaproic acid and tranexamic acid are safe alternatives.

Adult↗

PubMed2006

A national evaluation of the effect of trauma-center care on mortality.

BACKGROUND: Hospitals have difficulty justifying the expense of maintaining trauma centers without strong evidence of their effectiveness. To address this gap, we examined differences in mortality between level 1 trauma centers and hospitals without a trauma center (non-trauma centers). METHODS: Mortality outcomes were compared among patients treated in 18 hospitals with a level 1 trauma center and 51 hospitals non-trauma centers located in 14 states. Patients 18 to 84 years old with a moderate-to-severe injury were eligible. Complete data were obtained for 1104 patients who died in the hospital and 4087 patients who were discharged alive. We used propensity-score weighting to adjust for observable differences between patients treated at trauma centers and those treated at non-trauma centers. RESULTS: After adjustment for differences in the case mix, the in-hospital mortality rate was significantly lower at trauma centers than at non-trauma centers (7.6 percent vs. 9.5 percent; relative risk, 0.80; 95 percent confidence interval, 0.66 to 0.98), as was the one-year mortality rate (10.4 percent vs. 13.8 percent; relative risk, 0.75; 95 percent confidence interval, 0.60 to 0.95). The effects of treatment at a trauma center varied according to the severity of injury, with evidence to suggest that differences in mortality rates were primarily confined to patients with more severe injuries. CONCLUSIONS: Our findings show that the risk of death is significantly lower when care is provided in a trauma center than in a non-trauma center and argue for continued efforts at regionalization.

Adolescent↗

PubMed2000

Abciximab provides cost-effective survival advantage in high-volume interventional practice.

BACKGROUND: Placebo-controlled randomized trials of platelet glycoprotein (GP) IIb/IIIa blockade during percutaneous coronary intervention have demonstrated efficacy of these agents for reducing the risk of periprocedural ischemic events. However, cost-effectiveness of this adjunctive pharmacotherapy has been scrutinized. Extrapolation of cost-efficacy observations from clinical trials to "real world" interventional practice is problematic. METHODS: Consecutive percutaneous coronary interventions (n = 1472) performed by Ohio Heart Health Center operators at The Christ Hospital, Cincinnati, Ohio, in 1997 were analyzed for procedural and long-term (6-month) outcomes and charges. Observations on cost and efficacy (survival) were adjusted for nonrandomized abciximab allocation by means of "propensity scoring" methods. RESULTS: Abciximab therapy was associated with a survival advantage to 6 months after percutaneous coronary intervention. The average reduction in mortality rate at 6 months was 3.4% (unadjusted) and 4.9% when adjusted for nonrandomization. The average charge increment to 6 months was $1512 (unadjusted) and $950 when adjusted for nonrandomization. Patients deriving the greatest reduction in mortality rates also had a reduction in total cardiovascular charges to 6 months. Distinguishing demographics of this population included multivessel coronary intervention, coronary stent deployment, intervention within 1 week of myocardial infarction, and lower left ventricular ejection fraction. The average cost per life-year gained in this study was $2875 for all patients (unadjusted) and $1243 when adjusted for nonrandomization. CONCLUSIONS: Abciximab provides a cost-effective survival advantage in high-volume interventional practice that compares favorably with currently accepted standards. Clinical and procedural demographics associated with increased cost-effectiveness included multivessel coronary intervention, stent deployment, recent (<1 week) myocardial infarction, and impaired left ventricular function.

Abciximab↗

PubMed2000

Abciximab: cost-effective survival advantage in clinical trials and clinical practice.

Adjunctive blockade of the platelet glycoprotein (GP) IIb/IIIa receptor during either percutaneous coronary intervention (PCI) or for patients who present with non-ST segment elevation acute coronary syndromes has demonstrated efficacy in reducing platelet-mediated adverse cardiovascular ischemic events. The three currently available agents (abciximab, eptifibatide, tirofiban) differ markedly in pharmacodynamic and pharmacokinetic profiles, receptor affinity, and cost. Although pharmacoeconomic substudies are available from placebo-controlled randomized trials of platelet GPIIb/IIIa blockade during PCI, "real-world" cost-effectiveness data from high-volume practice are lacking. Therefore, in-hospital and late (6-month) clinical outcomes and cumulative cost/charge data were analyzed on 1472 consecutive PCI procedures (70% received abciximab) performed by high-volume operators at a single institution.(1) Data were adjusted for lack of randomized treatment allocation with the use of a propensity scoring technique. Adjunctive abciximab therapy for PCI was associated with a significant (3.4%) reduction in mortality to 6 months. Based on the economic cost-effectiveness concept of cost per life year gained relative to standard therapy,(2,3) abciximab provided a cost-effective survival advantage in high-volume interventional practice that compares very favorably with currently accepted standards. Clinical and procedural demographics associated with increased cost-effectiveness include multivessel coronary intervention, stent deployment, recent (<1 week) myocardial infarction (MI), and impaired left-ventricular (LV) function.

Abciximab↗

PubMed2002

Amiodarone and mortality among elderly patients with acute myocardial infarction with atrial fibrillation.

BACKGROUND: Amiodarone has been shown to be safe in patients with acute myocardial infarction (AMI) who are at risk for sudden cardiac death. However, there is limited data concerning the safety of amiodarone in patients who experience AMI complicated by atrial fibrillation. METHODS: To determine the safety of amiodarone therapy, we conducted a retrospective analysis of elderly patients hospitalized with AMI who experienced atrial fibrillation and had survived to hospital discharge (n = 17,597). Amiodarone prescribed at discharge was evaluated for its association with short-term and long-term mortality in crude and adjusted analyses employing propensity score methods. RESULTS: Of the 17,597 patients, 550 patients (3.1%) were prescribed amiodarone, 2317 patients (13.2%) were prescribed other antiarrhythmic agents (excluded from analysis), and 14,730 (83.7%) were prescribed no antiarrhythmic medication at discharge. Thirty-day mortality rates were similar for patients prescribed amiodarone and those not prescribed amiodarone (6.8% amiodarone vs 5.4% no amiodarone, P =.21), but mortality at 1 year was higher among patients prescribed amiodarone (35.6% vs 31.6%, P =.001). However, amiodarone was not associated with mortality at 30 days (odds ratio 0.80, 95% CI 0.53-1.20) or at long-term follow-up (mean duration 612 days, hazard ratio 1.04, 95% CI 0.92-1.18) after multivariable modeling. CONCLUSIONS: Amiodarone was not independently associated with short-term or long-term mortality in elderly patients discharged after a hospitalization for AMI complicated by atrial fibrillation. Although our data suggest that amiodarone may be safe to use in this population, randomized controlled trial data are needed to confirm this finding.

Aged↗

PubMed2003

Continuous retrograde blood cardioplegia is associated with lower hospital mortality after heart valve surgery.

OBJECTIVE: Myocardial preservation studies comparing blood and crystalloid cardioplegia techniques were almost exclusively performed on patients undergoing coronary bypass, and they were unable to show a difference in hospital mortality. We investigated possible factors, including cardioplegia techniques, influencing hospital mortality in patients undergoing cardiac valve surgery. METHODS: We evaluated hospital mortality in 1098 consecutive patients undergoing cardiac valve surgery by using a multivariate logistic regression with propensity score balancing of the groups. In 25% of the patients, multiple valve or Bentall procedures were performed, and in 46% of all patients, coronary bypass grafting was associated with valve surgery. A first cohort of 504 consecutive patients were operated on by using single-shot antegrade cold crystalloid cardioplegia, and a second cohort of 594 patients were operated on by using continuous retrograde cold blood cardioplegia. RESULTS: After correction for patient-related and operative risk factors, lower hospital mortality was found in patients who received retrograde blood cardioplegia (P =.020). The odds ratio of in-hospital death when using blood cardioplegia was 0.44 (95% confidence interval, 0.22-0.88). Further predictors of hospital mortality were age, advanced New York Heart Association functional class, cardiopulmonary bypass time, reoperation, active endocarditis, and renal failure. CONCLUSIONS: This study shows that continuous retrograde blood cardioplegia is associated with lower hospital mortality in heart valve operations.

Adult↗

PubMed2005

A comparison of patient outcomes and quality of life in persons with neurogenic bowel: standard bowel care program vs colostomy.

BACKGROUND/OBJECTIVE: The purpose of this study was to compare patient outcomes and quality of life for people with neurogenic bowel using either a standard bowel care program or colostomy. METHODS: We analyzed survey data from a national sample, comparing outcomes between veterans with spinal cord injury (SCI) who perform bowel care programs vs individuals with colostomies. This study is part of a larger study to evaluate clinical practice guideline implementation in SCI. The sample included 1,503 veterans with SCI. The response rate was 58.4%. For comparison, we matched the respondents with colostomies to matched controls from the remainder of the survey cohort. A total of 74 veterans with SCI and colostomies were matched with 296 controls, using propensity scores. Seven items were designed to elicit information about the respondent's satisfaction with their bowel care program, whereas 7 other items were designed to measure bowel-related quality of life. RESULTS: No statistically significant differences in satisfaction or quality of life were found between the responses from veterans with colostomies and those with traditional bowel care programs. Both respondents with colostomies and those without colostomies indicated that they had received training for their bowel care program, that they experienced relatively few complications, such as falls as a result of their bowel care program, and that their quality of life related to bowel care was generally good. However, large numbers of respondents with colostomies (n = 39; 55.7%) and without colostomies (n = 113; 41.7%) reported that they were very unsatisfied with their bowel care program. CONCLUSION: Satisfaction with bowel care is a major problem for veterans with SCI.

Adult↗

PubMed2006

Multivariate causal attribution and cost-effectiveness of a national mass media campaign in the Philippines.

Cost-effectiveness analysis is based on a simple formula. A dollar estimate of the total cost to conduct a program is divided by the number of people estimated to have been affected by it in terms of some intended outcome. The direct, total costs of most communication campaigns are usually available. Estimating the amount of effect that can be attributed to the communication alone, however is problematical in full-coverage, mass media campaigns where the randomized control group design is not feasible. Single-equation, multiple regression analysis controls for confounding variables but does not adequately address the issue of causal attribution. In this article, multivariate causal attribution (MCA) methods are applied to data from a sample survey of 1,516 married women in the Philippines to obtain a valid measure of the number of new adopters of modern contraceptives that can be causally attributed to a national mass media campaign and to calculate its cost-effectiveness. The MCA analysis uses structural equation modeling to test the causal pathways and to test for endogeneity, biprobit analysis to test for direct effects of the campaign and endogeneity, and propensity score matching to create a statistically equivalent, matched control group that approximates the results that would have been obtained from a randomized control group design. The MCA results support the conclusion that the observed, 6.4 percentage point increase in modern contraceptive use can be attributed to the national mass media campaign and to its indirect effects on attitudes toward contraceptives. This net increase represented 348,695 new adopters in the population of married women at a cost of U.S. $1.57 per new adopter.

Causality↗

PubMed2002

Sample size calculation for a historically controlled clinical trial with adjustment for covariates.

We present a Bayesian approach to determining the optimal sample size for a historically controlled clinical trial. This work is motivated by a trial of a new coronary stent that uses a retrospective control group formed from seven trials of coronary stents currently marketed in the United States. In studies involving nonrandomized control groups, hierarchical regression, propensity score methods, or other sophisticated models are typically required to account for heterogeneity among groups which, if ignored could bias the results. Sample size calculations for historically controlled trials of medical devices are often based on formulae derived for randomized trials and fail to account for estimation of model parameters, correlation of observations, and uncertainty in the distribution of covariates of the patients recruited in the new trial. We propose methodology based on stochastic optimization that overcomes these deficiencies. The methodology is demonstrated using an objective function based on the power of the trial from a Bayesian approach. Analytic approximations based on a covariate-free analysis that convey features of the power function are developed. Our principle conclusions are that exact sample size calculations can be substantially different from current approximations, and stochastic optimization provides a convenient method of computation.

Bayes Theorem↗