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Prophylaxis with fluoroquinolones for bacterial infections in neutropenic patients: a meta-analysis.

We conducted a two-part meta-analysis to assess the effectiveness of fluoroquinolones for preventing bacterial infections in granulocytopenic patients who are receiving chemotherapy for malignancies. Overall, 19 randomized studies met selection criteria and were included in this meta-analysis of 2,112 patients. Thirteen studies that compared the fluoroquinolones alone with control regimens (co-trimoxazole, oral nonabsorbable antibiotics, or placebo) and six studies that compared the fluoroquinolones plus prophylaxis for bacteremia due to gram-positive bacteria with control regimens (fluoroquinolones or oral nonabsorbable antibiotics) were included in the two meta-analyses. The results of the first meta-analysis indicate that fluoroquinolones alone are effective in preventing gram-negative bacteremia (overall odds ratio [OR], 0.09; 95% confidence interval [CI], 0.05-0.16; P < .001), but not gram-positive bacteremia (OR, 1.05; 95% CI, 0.76-1.45; P = .7), fever-related morbidity (OR, 0.76; 95% CI, 0.56-1.04; P = .09), and infection-related mortality (OR, 0.79; 95% CI, 0.47-1.34; P = .4). The results of the second meta-analysis indicate that a combination of fluoroquinolones plus prophylaxis for gram-positive bacteremia (penicillin, vancomycin, or macrolides) significantly reduces the occurrence of gram-positive bacteremia (OR, 0.46; CI, 0.33-0.63; P < .001) without affecting the incidence of fever-related morbidity (OR, 0.83; 95% CI, 0.62-1.13; P = .2) and infection-related mortality (OR, 0.74; 95% CI, 0.40-1.38; P = .3)

Anti-Bacterial Agents↗

Drug treatment of hypertension in the elderly: a meta-analysis.

PURPOSE: A meta-analysis of the effect of antihypertensive drug treatment on mortality and morbidity in elderly patients. DATA SOURCES: A literature search of published articles from January 1980 to February 1992. STUDY SELECTION: Randomized controlled trials of drug treatment of hypertension with end points for elderly patients reported separately. DATA EXTRACTION: Mortality or morbidity end points or both in patients older than 59 years were pooled by determination of typical odds ratio. A meta-regression was used to study heterogeneity. RESULTS: Nine major trials with 15,559 patients older than 59 years were identified. Death rates in the control group varied between 2.7% and 77.2%; stroke and coronary mortality increased with the severity-of-illness rank (P < 0.001). Overall, treated patients had an approximately 12% reduction in all-cause mortality (odds ratio, 0.88; 95% CI, 0.80 to 0.97; 953 events compared with 1069 events, P = 0.009). There was a 36% reduction in stroke mortality (odds ratio, 0.64; CI, 0.49 to 0.82; 94 events compared with 149 events, P < 0.001) and a 25% reduction in coronary heart disease mortality (odds ratio, 0.75; CI, 0.64 to 0.88; 263 events compared with 350 events, P < 0.001). Coronary morbidity was reduced 15% (odds ratio, 0.85; CI, 0.73 to 0.99; 325 events compared with 379 events, P = 0.036), and stroke morbidity was reduced 35% (odds ratio, 0.65; CI, 0.55 to 0.76; 247 events compared with 382 events, P < 0.001). CONCLUSION: Overall, treatment of hypertension in elderly patients produces a significant benefit in total mortality and cardiovascular morbidity and mortality. However, this benefit may be reduced in the oldest age groups.

Aged↗

Do nonsteroidal anti-inflammatory drugs affect blood pressure? A meta-analysis.

PURPOSE: A meta-analysis of randomized trials studying the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on blood pressure. DATA SOURCES AND STUDY SELECTION: Eight databases were searched, yielding 38 randomized, placebo-controlled trials and 12 randomized but not placebo-controlled trials (comparing two or more NSAIDs). DATA EXTRACTION: Pooled mean treatment effects were computed in each trial for blood pressure, weight, creatinine clearance, plasma renin activity, and daily urinary excretion of sodium and prostaglandins. Meta-analyses of these variables were done for all randomized, controlled trials; for all randomized, uncontrolled trials; and for several subgroups. DATA SYNTHESIS: When pooled, NSAIDs elevated supine mean blood pressure by 5.0 mm Hg (95% CI, 1.2 to 8.7 mm Hg) but had no effect on variables other than blood pressure. Nonsteroidal anti-inflammatory drugs antagonized the antihypertensive effect of beta-blockers (blood pressure elevation, 6.2 mm Hg; CI, 1.1 to 11.4 mm Hg) more than did vasodilators and diuretics. Among NSAIDs, piroxicam produced the most marked elevation in blood pressure (6.2 mm Hg; CI, 0.8 to 11.5 mm Hg), whereas sulindac and aspirin had the least hypertensive effect. CONCLUSIONS: Nonsteroidal anti-inflammatory drugs may elevate blood pressure and antagonize the blood pressure-lowering effect of antihypertensive medication to an extent that may potentially increase hypertension-related morbidity. Although certain NSAIDs and antihypertensive agents could be more likely to produce these effects, the underlying mechanisms require further study.

Adult↗

PYRAMA: an open-source tool for advanced meta-analysis of genome wide association studies.

MOTIVATION: Genome-wide association study (GWAS) meta-analysis tools are essential for integrating summary statistics across multiple cohorts, thereby increasing statistical power and validating genetic associations. Widely cited tools, such as METAL, PLINK, and GWAMA, have facilitated numerous significant discoveries in the field of GWAS. Nevertheless, these tools offer a limited set of meta-analysis methods and typically require users to have prior experience with command-line tools to be executed. RESULTS: We present here PYRAMA, an open-source tool which is designed for meta-analysis of genome wide association studies. This work introduces an easy-to-use software package that includes several meta-analysis methods that are absent in similar software packages. PYRAMA is faster compared to other tools, supports robust methods for analysis and meta-analysis, fixed-effects, random-effects and Bayesian meta-analysis and it is currently the only tool that supports meta-analysis with imputation of summary statistics. It is available both as a standalone tool and as a freely available web server. AVAILABILITY AND IMPLEMENTATION: https://github.com/pbagos/PYRAMA, https://doi.org/10.5281/zenodo.17830449.

Genome-Wide Association Study↗

Age differences and the identity negative priming effect: an updated meta-analysis.

A recent meta-analysis (P. Verhaeghen & L. De Meersman, 1998a) revealed that older adults show a reliable but significantly reduced negative priming effect compared with young adults. The present study provides an updated quantitative review on the effect of aging on the magnitude of the negative priming effect in identity tasks. This analysis demonstrated that the negative priming effect was not significantly different between young and old adults. This result differs from P. Verhaeghen and L. De Meersman's study. The implications of this finding for inhibitory-based theories of cognitive aging are discussed.

Adult↗

SPECT brain imaging in epilepsy: a meta-analysis.

UNLABELLED: A meta-analysis of SPECT brain imaging in epilepsy was performed to derive the sensitivity and specificity of interictal, postictal or ictal rCBF patterns to identify a seizure focus in medically refractory patients. METHODS: Papers were obtained by pooling all published articles identified by two independent literature searches: (a) Dialnet (EMBASE) or Radline by CD-ROM and (b) Current Contents searched manually. Literature inclusion criteria were: (a) patients had a localization-related epileptic syndrome; (b) more than six patients were reported; and (c) patients had at least an interictal EEG-documented epileptiform abnormality. Of 46 papers meeting these criteria, 30 contained extractable data. SPECT results were compared to localization by standard diagnostic evaluation and surgical outcome. Meta-analytic sensitivities for SPECT localization in patients with temporal lobe seizures relative to diagnostic evaluation were 0.44 (interictal), 0.75 (postictal) and 0.97 (ictal). Similar results were obtained relative to surgical outcome. False-positive rates were low relative to diagnostic evaluation (7.4% for interictal and 1.5% for postictal studies) and surgical outcome (4.4% for interictal and 0.0% for postictal studies). RESULTS: The results were not dependent on tracer used (or dose), the presence of CT-identified structural abnormalities, blinding of image interpretation or camera quality (although data were more variable with low-resolution cameras). There were insufficient data for conclusions regarding extratemporal-seizure or pediatric epilepsy populations. CONCLUSION: Insights gained from reviewing this literature yielded recommendations for minimal information that should be provided in future reports. Additional recommendations regarding the nature and focus of future studies also are provided. The most important of these is that institutions using SPECT imaging in epilepsy should perform ictal, preferably, or postictal scanning in combination with interictal scanning.

Brain↗

Meta-analysis. A useful tool for the spine researcher.

Meta-analysis is a systematic and objective methodology for synthesizing research literature. The authors present the history and definition of meta-analysis, discuss the generic framework for design and implementation of a meta-analysis, and review the problems and pitfalls that can accompany meta-analyses. Their discussion draws on practical experience with several meta-analyses of the low back pain literature. Meta-analysis can be used to help answer the questions about various options for diagnosis and treatment of low back problems and also to point out gaps in our knowledge base that may have a high priority for research. Meta-analytic methods are an informative means of addressing health care controversies with major patient management and cost implications.

Humans↗

Child sexual abuse prevention programs: a meta-analysis.

Conducted a meta-analytic evaluation of the effectiveness of school-based child abuse prevention programs. Literature searches identified 27 studies meeting inclusion criteria for use in this meta-analysis. The average effect size for all programs studied was 1.07, indicating that children who participated in prevention programs performed 1.07 SD higher than control group children on the outcome measures used in the studies. Analysis of moderator variables revealed significant effects for age, number of sessions, participant involvement, type of outcome measure, and use of behavioral skills training. Most important, programs presented over 4 or more sessions that allowed children to become physically involved produced the highest effect sizes. Although most often used only with younger children, findings suggest that active, long-term programs may be more effective for children of all ages.

Age Factors↗

Aging and the Stroop effect: a meta-analysis.

In this meta-analysis, data from 20 studies comparing younger and older adults on the Stroop interference effect, contained in 15 articles, were analyzed. No significant difference was found in the Stroop interference effect, expressed as mean standardized difference, between the 2 age groups (for younger adults: d = 2.04; for older adults: d = 2.17). Moderator variables were present, but these did not produce age differences. Brinley analysis showed that a single regression line with a slowing factor of 1.9 described the data well (R2 = .83) and confirmed that no Age x Condition interaction was present in the data. Likewise, no Age x Condition interaction was found when the data were fitted to the information loss model; the age ratio of decay rates was estimated to be 1.4. Consequently, the apparent age-sensitivity of the Stroop interference effect appears to be merely an artifact of general slowing.

Adult↗

When worlds collide. Social science, politics, and the Rind et al. (1998). Child sexual abuse meta-analysis.

A 1998 meta-analysis by B. Rind, P. Tromovitch, and R. Bauserman in Psychological Bulletin indicated that the relations between child sexual abuse and later psychopathology were weak in magnitude. Shortly thereafter, this article was condemned by media personality Dr. Laura Schlessinger and numerous conservative organizations and was denounced by the United States Congress. In addition, the American Psychological Association (APA) distanced itself from the authors' conclusions. This incident raises questions regarding (a) authors' responsibilities concerning the reporting of politically controversial findings, (b) academic and scientific freedom, (c) the role of the APA in disabusing the public and media of logical errors and fallacies, and (d) the substantial gap between popular and academic psychology and the responsibility of the APA to narrow that gap.

Child↗

Comparison of carbamazepine and lithium in the prophylaxis of bipolar disorders. A meta-analysis.

BACKGROUND: This meta-analysis assessed the equipotency of carbamazepine and lithium prophylaxis in bipolar disorder. METHOD: We selected only randomised, double-blind, controlled studies comparing carbamazepine with lithium from a manual and computerised search, and subjected them to a quality inventory. Their statistical results were weighted by their quality score and combined. RESULTS: Four studies met our criteria, yielding, overall, P = 0.15. This result is not straightforward because the studies showed significant heterogeneity (P < 0.01). CONCLUSION: Differences in statistical power and sensitivity of outcome measure explain this heterogeneity and the conflicting results of the studies. Therefore, the prophylactic efficacy of carbamazepine remains questionable.

Bipolar Disorder↗

Vaginal douching and adverse health effects: a meta-analysis.

OBJECTIVES: The meta-analysis described here reviewed the current literature on adverse health effects of vaginal douching. METHODS: Papers published in English from 1965 through 1995 were potentially eligible. RESULTS: One third of White women and two thirds of Black women of reproductive age reported douching regularly. Analyses indicated that vaginal douching increases the overall risk of pelvic inflammatory disease by 73% and the risk of ectopic pregnancy by 76%. Frequent douching was shown to be highly associated with pelvic inflammatory disease and modestly associated with cervical cancer. CONCLUSIONS: Current literature suggests that frequent douching increases the risk of pelvic inflammatory disease, ectopic pregnancy, and, possibly, cervical cancer.

Female↗

Maternal cigarette smoking and oral clefts: a meta-analysis.

OBJECTIVE: A meta-analysis was performed to estimate the association between maternal cigarette smoking and the risk of having a child with a nonsyndromic oral cleft (NSOC). DESIGN: Studies published from 1966 through 1996 were retrieved using MEDLINE, Current Contents, bibliographies, and other sources. MEDLINE and Current Contents search terms included "oral clefts," "cigarette smoking," "birth defects," and "congenital malformations." Cohort and case-control studies that enrolled oral cleft patients [cleft lip with or without cleft palate (CL/P), cleft palate (CP), or both] and controls, and presented information on maternal cigarette exposure during pregnancy were included in the analysis. Descriptive and outcome data from each study were independently abstracted by two authors. RESULTS: The overall odds ratio of the 11 studies satisfying criteria was 1.29 [95% confidence interval (CI), 1.18 to 1.42] for CL/P and 1.32 (95% CI: 1.10 to 1.62) for CP, indicating a small increase risk of having a child with either a CL/P or a CP for mothers who smoke during the first trimester of the pregnancy. CONCLUSIONS: These analyses suggest a small but statistically significant association between maternal cigarette smoking during the first trimester of gestation and increased risk of having a child with a CL/P or CP.

Cleft Lip↗

The effect of human chorionic gonadotropin (HCG) in the treatment of obesity by means of the Simeons therapy: a criteria-based meta-analysis.

1. A meta-analysis was conducted to assess if there is scientific ground for the use of human chorionic gonadotropin (HCG) as adjunctive therapy in the treatment of obesity. 2. Published papers relating to eight controlled and 16 uncontrolled trials that measured the effect of HCG in the treatment of obesity were traced by computer-aided search and citation tracking. 3. The trials were scored for the quality of the methods (based on four main categories: study population, interventions, measurement of effect, and data presentation and analysis) and the main conclusion of author(s) with regard to weight-loss, fat-redistribution, hunger, and feeling of well-being. 4. Methodological scores ranged from 16 to 73 points (maximum score 100), suggesting that most studies were of poor methodological quality. Of the 12 studies scoring 50 or more points, one reported that HCG was a useful adjunct. The studies scoring 50 or more points were all controlled. 5. We conclude that there is no scientific evidence that HCG is effective in the treatment of obesity; it does not bring about weight-loss of fat-redistribution, nor does it reduce hunger or induce a feeling of well-being.

Body Weight↗

The role of BCG in prevention of leprosy: a meta-analysis.

The present meta-analysis investigates the role of BCG-a widely used yet controversial vaccine-in the prevention of leprosy. The electronic databases Medline, Embase, the Cochrane Library, and LILACS were searched to identify studies assessing the protective effect of BCG against leprosy. We included seven experimental studies and 19 observational studies. The experimental studies demonstrated an overall protective effect of 26% (95% CI 14-37%). At 61% (95% CI 51-70%), the observational studies overestimated the protective effect. The age at vaccination did not predict the protective effect of BCG. An additional dose of BCG was more protective in the prevention of leprosy compared with a single dose. An additional dose of BCG may be warranted for contacts of leprosy patients in areas where leprosy continues to be a public-health problem.

Adolescent↗

Negative life events and depression in elderly persons: a meta-analysis.

In a meta-analysis of 25 studies, the relationship of both specific types of negative life events and the total number of experienced events to depression in old age was studied. Almost all negative life events appeared to have a modest but significant relationship with depression. The total number of negative life events and the total number of daily hassles appeared to have the strongest relationship with depression (respectively, combined r =.15, n = 5,037, and combined r =.41, n = 461), whereas sudden unexpected events were the only cluster of negative life events that seemed not to be related to depression scores (combined r =.05, n = 857). These findings suggest that providers and developers of intervention and prevention programs for elderly people should pay attention to the occurrence of negative life events. Special attention should be given to elderly people who have experienced an accumulation of stressful events and daily hassles, because they seem to be a group at greater risk.

Adaptation, Psychological↗

RankProd: a bioconductor package for detecting differentially expressed genes in meta-analysis.

UNLABELLED: While meta-analysis provides a powerful tool for analyzing microarray experiments by combining data from multiple studies, it presents unique computational challenges. The Bioconductor package RankProd provides a new and intuitive tool for this purpose in detecting differentially expressed genes under two experimental conditions. The package modifies and extends the rank product method proposed by Breitling et al., [(2004) FEBS Lett., 573, 83-92] to integrate multiple microarray studies from different laboratories and/or platforms. It offers several advantages over t-test based methods and accepts pre-processed expression datasets produced from a wide variety of platforms. The significance of the detection is assessed by a non-parametric permutation test, and the associated P-value and false discovery rate (FDR) are included in the output alongside the genes that are detected by user-defined criteria. A visualization plot is provided to view actual expression levels for each gene with estimated significance measurements. AVAILABILITY: RankProd is available at Bioconductor http://www.bioconductor.org. A web-based interface will soon be available at http://cactus.salk.edu/RankProd

Computational Biology↗

Accuracy of diagnostic imaging techniques in the diagnosis of aseptic loosening of the femoral component of a hip prosthesis: a meta-analysis.

In this meta-analysis we included 32 English-language articles published between January 1975 and June 2004 on the diagnostic performance of plain radiography, subtraction arthrography, nuclear arthrography and bone scintigraphy in detecting aseptic loosening of the femoral component, using criteria based on the Cochrane systematic review of screening and diagnostic tests. The mean sensitivity and specificity were, respectively, 82% (95% confidence interval (CI) 76 to 87) and 81% (95% CI 73 to 87) for plain radiography and 85% (95% CI 75 to 91) and 83% (95% CI 75 to 89) for nuclear arthrography. Pooled sensitivity and specificity were, respectively, 86% (95% CI 74 to 93) and 85% (95% CI 77 to 91) for subtraction arthrography and 85% (95% CI 79 to 89) and 72% (95% CI 64 to 79) for bone scintigraphy. Although the diagnostic performance of the imaging techniques was not significantly different, plain radiography and bone scintigraphy are preferred for the assessment of a femoral component because of their efficacy and lower risk of patient morbidity.

Arthrography↗