Home  About us  Contact
 

Effects Meta-analysis (effects + meta-analysi)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Effects Meta-analysis

  • random effects meta-analysi
    		•

    Selected Abstracts

    Mania associated with antidepressant treatment: comprehensive meta-analytic review

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010
    L. Tondo
    Tondo L, Vázquez G, Baldessarini RJ. Mania associated with antidepressant treatment: comprehensive meta-analytic review. Objective:, To review available data pertaining to risk of mania,hypomania among bipolar (BPD) and major depressive disorder (MDD) patients with vs. without exposure to antidepressant drugs (ADs) and consider effects of mood stabilizers. Method:, Computerized searching yielded 73 reports (109 trials, 114 521 adult patients); 35 were suitable for random effects meta-analysis, and multivariate-regression modeling included all available trials to test for effects of trial design, AD type, and mood-stabilizer use. Results:, The overall risk of mania with/without ADs averaged 12.5%/7.5%. The AD-associated mania was more frequent in BPD than MDD patients, but increased more in MDD cases. Tricyclic antidepressants were riskier than serotonin-reuptake inhibitors (SRIs); data for other types of ADs were inconclusive. Mood stabilizers had minor effects probably confounded by their preferential use in mania-prone patients. Conclusion:, Use of ADs in adults with BPD or MDD was highly prevalent and moderately increased the risk of mania overall, with little protection by mood stabilizers. [source]

    Outcome of secondary root canal treatment: a systematic review of the literature

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 12 2008
    Y.-L. Ng
    Abstract Aims, (i) To investigate the effects of study characteristics on the reported success rates of secondary root canal treatment (2°RCT or root canal retreatment); and (ii) to investigate the effects of clinical factors on the success of 2°RCT. Methodology, Longitudinal human clinical studies investigating outcome of 2°RCT which were published upto the end of 2006 were identified electronically (MEDLINE and Cochrane database 1966,2006 Dec, week 4). Four journals (Dental Traumatology, International Endodontic Journal, Journal of Endodontics, Oral Surgery Oral Medicine Oral Pathology Endodontics Radiology), bibliographies of all relevant papers and review articles were hand-searched. Two reviewers (Y-LN, KG) independently assessed and selected the studies based on specified inclusion criteria and extracted the data onto a pre-designed proforma, independently. The criteria were: (i) Clinical studies on 2°RCT; (ii) Stratified analyses available for 2°RCT where 1°RCT data included; (iii) Sample size given and larger than 10; (iv) At least 6-month post-operative review; (v) Success based on clinical and/or radiographic criteria (strict = absence of apical radiolucency; loose = reduction in size of radiolucency); and (vi) Overall success rate given or could be calculated from the raw data. Three strands of evidence or analyses were used to triangulate a consensus view. The reported findings from individual studies, including those excluded for quantitative analysis, were utilized for the intuitive synthesis which constituted the first strand of evidence. Secondly, the pooled weighted success rates by each study characteristic and potential prognostic factor were estimated using the random effect model. Thirdly, the effects of study characteristics and prognostic factors (expressed as odds ratios) on success rates were estimated using fixed and random effects meta-analysis with DerSimonean and Laird's methods. Meta-regression models were used to explore potential sources of statistical heterogeneity. Study characteristics considered in the meta-regression analyses were: decade of publication, study-specific criteria for success (radiographic, combined radiographic & clinical), unit of outcome measure (tooth, root), duration after treatment when assessing success (,at least 4 years' or ,<4 years'), geographic location of the study (North American, Scandinavian, other countries), and qualification of the operator (undergraduate students, postgraduate students, general dental practitioners, specialist or mixed group). Results, Of the 40 papers identified, 17 studies published between 1961 and 2005 were included; none were published in 2006. The majority of studies were retrospective (n = 12) and only five prospective. The pooled weighted success rate of 2°RCT judged by complete healing was 76.7% (95% CI 73.6%, 89.6%) and by incomplete healing, 77.2% (95% CI 61.1%, 88.1%). The success rates by ,decade of publication' and ,geographic location of study' were not significantly different at the 5% level. Eighteen clinical factors had been investigated in various combinations in previous studies. The most frequently and thoroughly investigated were ,periapical status' (n = 13), ,size of lesion' (n = 7), and ,apical extent of RF' (n = 5) which were found to be significant prognostic factors. The effect of different aspects of primary treatment history and re-treatment procedures has been poorly tested. Conclusions, The pooled estimated success rate of secondary root canal treatment was 77%. The presence of pre-operative periapical lesion, apical extent of root filling and quality of coronal restoration proved significant prognostic factors with concurrence between all three strands of evidence whilst the effects of 1°RCT history and 2°RCT protocol have been poorly investigated. [source]

    Outcome of secondary root canal treatment , Systematic review of the literature

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2007
    Y.-L. Ng
    Aims, To assess the success rates of secondary root canal treatment (2oRCT) and identify factors influencing outcome. Methodology, Longitudinal clinical studies investigating outcome of 2oRCT were identified by electronic (medline) and hand searches. Inclusion criteria were data on: number of samples, those successful and definition of success. Two reviewers independently assessed the studies and extracted the data onto a proforma. The pooled weighted success rates by each potential prognostic factor were estimated using the binomial random effect model (MLwiN version 2.02) whilst their pooled effects (expressed as odds ratio) on success rates were estimated using fixed and random effects meta-analysis with DerSimonean and Laird's methods (Stata version 9.2). Meta-regression models were used to explore potential sources of statistical heterogeneity. Study characteristics considered in the meta-regression analyses were: decade of publication, study-specific criteria for success (radiographic, combined radiographic & clinical), unit of outcome measure (tooth and root), duration after treatment when assessing success (at least 4 years or shorter), geographic location of the study (North American, Scandinavian and other countries), and qualification of the operator (undergraduate students, postgraduate students, general dental practitioners, specialist or mixed group). Results, Of the 41 studies identified, 18 studies published between 1921 and 2005 were included. The majority of studies were retrospective (n = 13) and only five prospective. The pooled weighted success rate of 2oRCT judged by complete healing was 77.6% (95% CI 73.2%, 81.4%) and by incomplete healing, 77.4% (95% CI 64.1%, 86.7%). The success rates were similar by ,year of publication' and ,country of study'. Eighteen clinical factors were investigated in various combinations in previous studies. The most frequently investigated were ,periapical status' (n = 13), ,size of lesion' (n = 7), ,culture results prior to RF' (n = 5), and ,apical extent of root filling (RF)' (n = 4). The effect of different aspects of previous treatment and re-treatment technique has been poorly tested. Conclusions, The pooled weighted estimated success rate of 2oRCT was 77%, which was significantly (P , 0.001) influenced by the presence and size of pre-operative periapical lesion. The effects of existing canal content, procedural error and re-treatment technique were poorly investigated. [source]

    Meta-analyses of the effect of false-positive mammograms on generic and specific psychosocial outcomes

    PSYCHO-ONCOLOGY, Issue 10 2010
    Talya Salz
    Abstract Objectives: While a previous meta-analysis found that false-positive mammography results affect women's likelihood of returning for screening, effects on well being have yet to be meta-analyzed. We investigated whether the effects of false-positive mammograms on women's well-being are limited to outcomes specific to breast cancer. Methods: We searched MEDLINE for studies of the psychosocial effects of false-positive results of routine screening mammography. We pooled effect sizes using random effects meta-analysis. Results: Across 17 studies (n=20,781), receiving a false-positive mammogram the result was associated with differences in all eight breast-cancer-specific outcomes that we examined. These included greater anxiety and distress about breast cancer as well as more frequent breast self-exams and higher perceived effectiveness of screening mammography. False positives were associated with only one of six generic outcomes (i.e. generalized anxiety), and this effect size was small. Conclusions: False-positive mammograms influenced women's well-being, but the effects were limited to breast-cancer-specific outcomes. Researchers should include disease-specific measures in future studies of the consequences of false-positive mammograms. Copyright © 2010 John Wiley & Sons, Ltd. [source]

    Quantifying the duration of pre-diabetes

    AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 3 2010
    Melanie Y. Bertram
    Abstract Objective: Interventions for individuals with pre-diabetes are efficacious, however, identification of people with pre-diabetes does not occur in Australia. This study aims to calculate the duration of pre-diabetes, in order to provide supporting evidence for a screening program. Methods: We carried out a systematic review and random effects meta-analysis to identify if an increased risk of mortality is present in people with pre-diabetes. The result of this meta-analysis as well as information on prevalence, remission of pre-diabetes and transition to diabetes from an Australian cohort study, were used in the software program DisMod to calculate duration. Results: From 2,578 articles identified, 11 studies met the inclusion criteria. The pooled relative risk of all-cause mortality was 1.26 (1.17-1.34) with no sign of heterogeneity between the studies. The average duration of pre-diabetes was 8.5 years in males aged 30+ and 10.3 years in females aged 30+. Conclusions: The duration of pre-diabetes in Australia is long enough to warrant a screening program. The finding is robust to sensitivity testing of very large variations in the epidemiological parameters. Implications: If the interventions following screening are shown to be cost-effective, a strong rationale for the implementation of a screening program exists. [source]

    A multi-centre study of candidate genes for wheeze and allergy: the International Study of Asthma and Allergies in Childhood Phase 2

    CLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2009
    J. Genuneit
    Summary Background Common polymorphisms have been identified in genes suspected to play a role in asthma. We investigated their associations with wheeze and allergy in a case,control sample from Phase 2 of the International Study of Asthma and Allergies in Childhood. Methods We compared 1105 wheezing and 3137 non-wheezing children aged 8,12 years from 17 study centres in 13 countries. Genotyping of 55 candidate single nucleotide polymorphisms (SNPs) in 14 genes was performed using the Sequenom System. Logistic regression models were fitted separately for each centre and each SNP. A combined per allele odds ratio and measures of heterogeneity between centres were derived by random effects meta-analysis. Results Significant associations with wheeze in the past year were detected in only four genes (IL4R, TLR4, MS4A2, TLR9, P<0.05), with per allele odds ratios generally <1.3. Variants in IL4R and TLR4 were also related to allergen-specific IgE, while polymorphisms in FCER1B (MS4A2) and TLR9 were not. There were also highly significant associations (P<0.001) between SPINK5 variants and visible eczema (but not IgE levels) and between IL13 variants and total IgE. Heterogeneity of effects across centres was rare, despite differences in allele frequencies. Conclusions Despite the biological plausibility of IgE-related mechanisms in asthma, very few of the tested candidates showed evidence of association with both wheeze and increased IgE levels. We were unable to confirm associations of the positional candidates DPP10 and PHF11 with wheeze, although our study had ample power to detect the expected associations of IL13 variants with IgE and SPINK5 variants with eczema. [source]