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S Saint

Publications and source records attributed to S Saint.

51 records · Page 3Linked to original sources
PubMed1999

The use of meta-analysis in cost-effectiveness analysis. Issues and recommendations.

Meta-analysis is used to statistically pool the results from individual studies, usually randomised trials, to obtain an estimate of the summary effect size across studies. The summary measure from a meta-analysis is often used to derive the probability of treatment success in a cost-effectiveness analysis. Recently, LeLorier and colleagues questioned the ability of meta-analysis to accurately predict the results of a subsequent large-scale trial, implying that the use of a summary measure from a meta-analysis may be inappropriate in an economic evaluation. We comment on this potential shortcoming by first providing an outline of the use of meta-analysis results in a cost-effectiveness analysis. Then, using examples of discrepancies between meta-analyses and subsequent large trials noted by LeLorier and colleagues, we examine the potential impact of using the results from a small trial versus a meta-analysis. We found that the meta-analyses were comparable to or better than small trials at predicting the results of subsequent large trials. We, therefore, argue that a meta-analysis of homogeneous studies can provide a reasonable estimate of the treatment effect for use in a cost-effectiveness analysis when no large, definitive clinical trial has been performed. However, care must be taken not to over-interpret the precision of the estimate, since both the homogeneity and quality of the primary studies need to be considered. We conclude by providing guidance on the appropriate use of summary measures derived from meta-analyses for cost-effectiveness studies.

Cost-Benefit Analysis↗
PubMed1998

The efficacy of silver alloy-coated urinary catheters in preventing urinary tract infection: a meta-analysis.

PURPOSE: Indwelling urinary catheters are implicated in most cases of nosocomial urinary tract infection. Silver-coating of catheters may reduce the risk of these infections; however, trials have provided mixed results. We performed a meta-analysis to estimate the effectiveness of silver-coated urinary catheters. SUBJECTS AND METHODS: Published or unpublished articles were sought using MEDLINE, reference review, and correspondence with original authors, catheter manufacturers, and experts. Trials using silver-coated urinary catheters in the treatment group and uncoated urinary catheters in the control group were included. Bacteriuria, as evaluated by urine culture, was the outcome variable used to indicate urinary tract infection. Summary odds ratios (OR) and 95% confidence intervals (CI) were calculated using Mantel-Haenszel methods with a fixed-effects model. RESULTS: Of 117 reports retrieved, eight trials with a total of 2,355 patients satisfied inclusion criteria. The summary OR for urinary tract infection was 0.59 (95% CI, 0.42 to 0.84) indicating a significant benefit in the patients receiving silver-coated catheters. A test of heterogeneity, however, indicated that the odds ratios varied significantly among studies. Silver alloy catheters (OR = 0.24; 95% CI, 0.11 to 0.52) were significantly more protective against bacteriuria than silver oxide catheters (OR = 0.79; 95% CI, 0.56 to 1.10). CONCLUSIONS: This meta-analysis clarifies discrepant results among trials of silver-coated urinary catheters by revealing that silver alloy catheters are significantly more effective in preventing urinary tract infections than are silver oxide catheters. Though silver alloy urinary catheters cost about $6 more than standard urinary catheters, they may be worth the extra cost since catheter-related infection is a common cause of nosocomial infection and bacteremia.

Alloys↗
PubMed1998

Risk reduction in the intensive care unit.

Many potentially preventable complications occur in patients who receive intensive care. We have reviewed the epidemiology of three important complications (venous thromboembolism, stress-related upper gastrointestinal bleeding, and vascular catheter-related infection) and evaluated common preventive treatments to provide evidence-based recommendations for prevention. We used English language articles located by MEDLINE or cross-citation, giving preference to articles published in the last 10 years, meta-analyses, and clinical trials that were randomized, double-blinded, and used intention-to-treat analysis. We recommend prophylaxis against venous thromboembolism in most patients, whereas those without respiratory failure or coagulopathy may not require prophylaxis against stress-related upper gastrointestinal hemorrhage. Chlorhexidine gluconate is the preferred antiseptic for disinfecting the skin prior to and during intravascular catheterization. Central venous catheters impregnated with antibacterial or antiseptic agents should be considered in patients at high risk for vascular catheter-related infection. Finally, central venous, pulmonary arterial, and systemic arterial catheters should be changed only when clinically indicated.

Arteries↗
PubMedDate not supplied

Potential clinical and economic effects of homocyst(e)ine lowering.

BACKGROUND: Elevated total homocyst(e)ine levels (>/=11 micromol/L) have been identified as a potential risk factor for coronary heart disease. However, the benefits expected from lowering homocyst(e)ine levels with folic acid and vitamin B(12) supplementation have yet to be demonstrated in clinical trials. SUBJECTS AND METHODS: We constructed a decision analytic model to estimate the clinical benefits and economic costs of 2 homocyst(e)ine-lowering strategies: (1) "treat all"-no screening, daily supplementation with folic acid (400 microg) and vitamin B(12) (cyanocobalamin; 500 microg) for all; (2) "screen and treat"-screening, followed by daily supplementation with folic acid and vitamin B(12) for individuals with elevated homocyst(e)ine levels. Simulated cohorts of 40-year-old men and 50-year-old women in the general population were evaluated. In the base-case analysis, we assumed that lowering elevated levels would reduce excess coronary heart disease risk by 40%; however, this assumption and others were evaluated across a broad range of potential values using sensitivity analysis. Primary outcomes were discounted costs per life-year saved. RESULTS: Although the treat-all strategy was slightly more effective overall, the screen and treat strategy resulted in a much lower cost per life-year saved ($13,600 in men and $27,500 in women) when compared with no intervention. Incremental cost-effectiveness ratios for the treat-all strategy compared with the screen and treat strategy were more than $500,000 per life-year saved in both cohorts. Sensitivity analysis showed that cost-effectiveness ratios for the screen and treat strategy remained less than $50,000 per life-year saved under several unfavorable scenarios, such as when effective homocyst(e)ine lowering was assumed to reduce the relative risk of coronary heart disease-related death by only 11% in men or 23% in women. CONCLUSIONS: Homocyst(e)ine lowering with folic acid and vitamin B(12) supplementation could result in substantial clinical benefits at reasonable costs. If homocyst-(e)ine lowering is considered, a screen and treat strategy is likely to be more cost-effective than universal supplementation. Arch Intern Med. 2000;160:3406-3412.

Coronary Disease↗
PubMedDate not supplied

Four-year prospective evaluation of community-acquired bacteremia: epidemiology, microbiology, and patient outcome.

The objectives of this study were to (1) describe the epidemiology and microbiology of community-acquired bacteremia; (2) determine the crude mortality associated with such infections; and (3) identify independent predictors of mortality. All patients with clinically significant community-acquired bacteremia admitted to a university-affiliated Veterans Affairs medical center from January 1994 through December 1997 were evaluated. During the study period, 387 bacteremic episodes occurred in 334 patients. Staphylococcus aureus, Escherichia coli, and coagulase-negative staphylococci were the most commonly isolated organisms; the most frequent sources were the urinary tract and intravascular catheters. Approximately 14% of patients died. Patient characteristics independently associated with increased mortality included shock (OR 3.7, p = 0.02) and renal failure (OR 4.0, p = 0.003). The risk of death was also higher in those whose source was pneumonia (OR 6.3, p = 0.03) or an intra-abdominal site (OR 10.7, p = 0.02), or if multiple sources were identified (OR 13.4, p = 0.003). Community-acquired bacteremia is often device-related and may be preventable. Strategies that have been successful in preventing nosocomial device-related bacteremia should be adapted to the outpatient setting.

Adult↗
PubMedDate not supplied

Is hospitalism new? An analysis of medicare data from Washington State in 1994.

CONTEXT: Managed care, increased disease severity, and more complex treatment options may be reasons for the recent enthusiasm for "hospitalists"--physicians who specialize in the care of inpatients. It is not clear, however, whether hospitalism is a new model for caring for inpatients or merely a new description for previously existing practice patterns. PRACTICE PATTERNS EXAMINED: The proportion of physician visits occurring in the hospital before the introduction of the term hospitalists. Five specialties were examined: family/general practice, general internal medicine, cardiology, gastroenterology, and pulmonology. DATA SOURCE: 1994 Medicare Part B claims data for beneficiaries 65 years of age and older who received all of their care in Washington State. RESULTS: For the average family/general practitioner, 10% of all Medicare visits occurred in the hospital. Corresponding figures for the other specialties were 20% for general internists, 36% for cardiologists, 38% for gastroenterologists, and 45% for pulmonologists. A substantial number of physicians devoted most of their Medicare effort to inpatient care (i.e., hospital visits > 50% of total visits). If this definition were used as a proxy for hospitalism, 4% of family/general practitioners, 10% of general internists, 20% of gastroenterologists, 29% of cardiologists, and 37% of pulmonologists would have been considered hospitalists in Washington State during 1994. On the other hand, 35% of family/general practitioners, 18% of general internists, 7% of both gastroenterologists and pulmonologists, and 4% of cardiologists did not bill Medicare for any inpatient visits and could reasonably be categorized as "officists." CONCLUSION: Physicians vary considerably in the proportion of their workload that occurs in the hospital or outpatient setting. Even before the term was coined, a considerable number of physicians were de facto "hospitalists."

Aged↗
PubMedDate not supplied

Antibiotics in chronic obstructive pulmonary disease exacerbations. A meta-analysis.

OBJECTIVE: A meta-analysis of randomized trials was performed to estimate the effectiveness of antibiotics in treating exacerbations of chronic obstructive pulmonary disease (COPD). DATA SOURCES: English-language studies published from 1955 through 1994 were retrieved using MEDLINE, Index Medicus, bibliographies, and consultation with experts. MEDLINE search terms included "COPD," "chronic bronchitis," and "antibiotic(s)." STUDY SELECTION: Only randomized trials that enrolled patients having an exacerbation of COPD, used an antibiotic in the treatment group and placebo in the control group, and provided sufficient data to calculate an effect size were included in the meta-analysis. DATA EXTRACTION: Descriptive and outcome data from each study were independently in the meta-analysis. DATA SYNTHESIS: Overall summary effect size of the nine trials satisfying all inclusion criteria was 0.22 (95% confidence interval [CI], 0.10 to 0.34), indicating a small benefit in the antibiotic-treated group. Similar analysis of the six studies that provided data on peak expiratory flow rate changes revealed a summary effect size of 0.19 (95% CI, 0.03 to 0.35) and a summary change in peak expiratory flow rate of 10.75 L/min (95% CI, 4.96 to 16.54 L/min) in favor of the antibiotic-treated group. Sensitivity analyses did not significantly affect these results. CONCLUSIONS: These analyses suggest a small but statistically significant improvement due to antibiotic therapy in patients with exacerbations of COPD. This antibiotic-associated improvement may be clinically significant, especially in patients with low baseline flow rates.

Anti-Bacterial Agents↗