16 results on '"Gøtzsche, Peter C."'
Search Results
2. Benefits and harms of the human papillomavirus (HPV) vaccines: systematic review with meta-analyses of trial data from clinical study reports
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Jørgensen, Lars, Gøtzsche, Peter C., and Jefferson, Tom
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- 2020
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3. Drop-out rates in placebo-controlled trials of antidepressant drugs: A systematic review and meta-analysis based on clinical study reports.
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Sharma, Tarang, Guski, Louise Schow, Freund, Nanna, Meng, Dina Muscat, and Gøtzsche, Peter C.
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DRUG side effects ,CONFIDENCE intervals ,META-analysis ,NORADRENALINE ,SEROTONIN uptake inhibitors ,SYSTEMATIC reviews ,DATA analysis ,ODDS ratio - Abstract
OBJECTIVE: To study the drop-out rates in trials of selective serotonin and serotonin-norepinephrine reuptake inhibitors (SSRIs and SNRIs). METHODS: This study is a systematic review and meta-analysis of trials. The main outcome measure: Overall drop-out rate. Secondary outcomes were drop-outs due to adverse events and lack of effect. We obtained clinical study reports (CSRs) of five antidepressant drugs from the European Medicines Agency and the UK's Medicines and Healthcare products Regulatory Agency. The eligibility criteria for selecting studies: double-blind randomised, placebo-controlled trials for any indication. Data extraction and analysis: The primary outcome was extracted by two researchers independently and meta-analysed using the Mantel-Haenszel method (fixed effect model). The secondary outcomes were extracted by one researcher and checked by another. Sensitivity analyses were performed using Peto's odds ratio and beta binomial methods, due to presence of null events, and by excluding unreliable trials. RESULTS: We included 71 CSRs (67,319 pages) with information on 73 trials (11,057 patients on SSRI or SNRI drugs, and 7,369 on placebo). There were minor discrepancies within the CSRs when a modified intention to treat principle was used and patients lost to follow up early in the trial were not accounted for. Significantly more patients dropped out on active drug than on placebo, risk ratio 1.08 (95% CI 1.03 to 1.13), with no difference between adults and children/ adolescents, RR = 1.08 (1.03 to 1.13) and 1.07 (0.95 to 1.21), respectively. When three trials with a prior single-blind phase on active drug were removed, the difference was a risk ratio of 1.12 (1.07 to 1.18), whereas the result was the same after removal of three trials with fraudulent data or other issues with data validity, risk ratio 1.08 (1.03 to 1.13). There were more drop-outs due to adverse events on active drug than on placebo, risk ratio 2.63 (2.33 to 2.96). There were fewer drop-outs due to lack of effect, risk ratio 0.47 (0.43 to 0.53). However, this result is biased; when more people drop out due to adverse effects, fewer can drop out because of lack of effect. CONCLUSIONS: By using CSRs, we were able to demonstrate for the first time that more patients dropped out on active drug than on placebo. As it can be argued that the drop-out rate reflects the patients' overall assessment of the balance between benefits and harms, our review adds to the growing concern that SSRIs and SNRIs might not have the desired effect. Our review also highlights the importance of using CSRs for undertaking reviews of drugs. [ABSTRACT FROM AUTHOR]
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- 2019
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4. Effect of lithium on suicide and mortality in mood disorders: A systematic review.
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Börjesson, Joakim and Gøtzsche, Peter C.
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THERAPEUTIC use of lithium , *SUICIDE prevention , *SUICIDE risk factors , *MORTALITY prevention , *AFFECTIVE disorders , *CONFIDENCE intervals , *MENTAL depression , *BIPOLAR disorder , *MEDLINE , *META-analysis , *ONLINE information services , *SCHIZOAFFECTIVE disorders , *SYSTEMATIC reviews , *ODDS ratio ,MORTALITY risk factors - Abstract
OBJECTIVE: To assess if lithium treatment in patients with mood disorders, for instance depression, bipolar disorders, and schizoaffective disorders, has an effect on total mortality and suicide. DESIGN: Systematic review and meta-analysis. MAIN OUTCOME MEASURE: Total mortality. Secondary outcome was suicide. DATA SOURCES: PubMed and ClinicalTrials.gov. Eligible trials were randomized double-blind trials comparing lithium with placebo in patients with mood disorders who were not already on lithium before randomization in order to avoid withdrawal effects in the placebo group. DATA EXTRACTION AND ANALYSIS: Two researchers extracted data independently. Data were analysed with Review Manager 5.3 (Peto odds ratio). RESULTS: We found 45 eligible studies. Only four studies reported any suicides or other deaths in the lithium or placebo group. There was a significant reduction in total mortality (two versus nine), odds ratio 0.28 (95% confidence interval 0.08 to 0.93). There was no statistically significant reduction in suicides, (none versus three), odds ratio 0.13 (0.01 to 1.27). CONCLUSION: According to our study, lithium reduces total mortality in mood disorders but not suicide. Because of small numbers and unreliable data, the findings should be interpreted with caution. [ABSTRACT FROM AUTHOR]
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- 2019
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5. Considering benefits and harms of duloxetine for treatment of stress urinary incontinence: a meta-analysis of clinical study reports.
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Maund, Emma, Guski, Louise Schow, and Gøtzsche, Peter C.
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DULOXETINE ,ADRENERGIC uptake inhibitors ,DOPAMINE uptake inhibitors ,URINARY incontinence ,CLINICAL trials ,ANTIDEPRESSANTS ,ALEXITHYMIA ,ANXIETY ,COMPARATIVE studies ,INSOMNIA ,RESEARCH methodology ,MEDICAL cooperation ,MENTAL illness ,META-analysis ,RESEARCH ,RISK assessment ,URINARY stress incontinence ,VIOLENCE ,SUBSTANCE-induced psychoses ,EVALUATION research ,TREATMENT effectiveness ,SUICIDAL ideation ,TARDIVE akathisia - Abstract
Background: The European Medicines Agency makes clinical study reports publicly available and publishes reasons for not approving applications for marketing authorization. Duloxetine has been approved in Europe for the treatment of stress urinary incontinence in women. The reported adverse effects of duloxetine include mental health problems and suicidality. We obtained clinical study reports from the European Medicines Agency concerning use of this drug for stress urinary incontinence.Methods: We performed a meta-analysis of 4 randomized placebo-controlled trials of duloxetine (involving a total of 1913 patients) submitted to the European Medicines Agency for marketing approval for the indication of stress urinary incontinence in women. We used data from the clinical study reports (totalling 6870 pages and including individual patient data) to assess benefits (including frequency of incontinence and changes in quality-of-life scores, such as Patient Global Impression of Improvement rating) and harms (both general harms, including discontinuation because of adverse events, and harms related to suicidality, violent behaviour and their potential precursors, such as akathisia and activation [stimulating effects such as insomnia, anxiety and agitation]).Results: Duloxetine was significantly better than placebo in terms of percentage change in weekly incontinence episodes (mean difference -13.56%, 95% confidence interval [CI] -21.59% to -5.53%) and change in Incontinence Quality of Life total score (mean difference 3.24, 95% CI 2.00 to 4.48). However, the effect sizes were small, and a sensitivity analysis (with removal of one trial) showed that the number needed to treat for a Patient Global Impression of Improvement rating of "much better or very much better" was 8 (95% CI 6 to 13). The numbers needed to harm were 7 (95% CI 6 to 8) for discontinuing because of an adverse event and 7 (95% CI 6 to 9) for experiencing an activation event. No suicidality, violence or akathisia events were noted.Interpretation: Although duloxetine is effective for stress urinary incontinence in women, the rates of associated harm were high when individual patient data were analyzed, and the harms outweighed the benefits. [ABSTRACT FROM AUTHOR]- Published
- 2017
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6. Impaired reproduction after exposure to ADHD drugs: Systematic review of animal studies.
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Danborg, Pia Brandt, Simonsen, Anders Lykkemark, and Gøtzsche, Peter C.
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ANIMAL experimentation ,ATTENTION-deficit hyperactivity disorder ,CLONIDINE ,COMPARATIVE studies ,CONFIDENCE intervals ,FERTILITY ,HUMAN reproduction ,MEDICAL information storage & retrieval systems ,MAMMALS ,MEDLINE ,META-analysis ,METHYLPHENIDATE ,ONLINE information services ,RATS ,VAGINA ,SYSTEMATIC reviews ,DESCRIPTIVE statistics - Abstract
BACKGROUND: Few studies have reported on long-term harms caused by ADHD drugs but they are known to impair growth. OBJECTIVE: To assess whether ADHD drugs impair reproduction in mammals. METHODS: Systematic review of reproduction in studies of animals treated with ADHD drugs. DATA SOURCES: PubMed, Biosis and EMBASE. RESULTS:We included 17 studies. The studies were generally of poor quality or poorly reported. Two studies reported the use of one of three advised randomisation methods. Fifteen studies used placebo which suggested blinding. On clonidine, the ability to produce offspring was reduced for male rats, which approached two females each. In one study, 10 treated rats produced no offspring while all four controls did. In another study, 10 treated rats impregnated nine females while 10 controls impregnated 16. On methylphenidate, vaginal opening was delayed in two studies (in one, the mean difference was 4.0 days, 95% CI 2.5 to 5.6, and number of estrous cycles was halved; in the other, the minimum delay was 6 days), while in two other studies no difference occurred. Generally, the impairments improved after a drug-free period and were less pronounced when treatment started later in life. CONCLUSION: ADHD drugs impair the reproduction in animals. [ABSTRACT FROM AUTHOR]
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- 2017
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7. The PRISMA Extension Statement for Reporting of Systematic Reviews Incorporating Network Meta-analyses of Health Care Interventions: Checklist and Explanations.
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Hutton, Brian, Salanti, Georgia, Caldwell, Deborah M., Chaimani, Anna, Schmid, Christopher H., Cameron, Chris, loannidis, John P. A., Straus, Sharon, Thorlund, Kristian, Jansen, Jeroen P., Mulrow, Cynthia, Catalá-López, Ferrán, Gøtzsche, Peter C., Dickersin, Kay, Boutron, Isabelle, Altman, Douglas G., and Moher, David
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GUIDELINES ,META-analysis ,SYSTEMATIC reviews ,MEDICAL research ,FORUMS - Abstract
The PRISMA statement is a reporting guideline designed to improve the completeness of reporting of systematic reviews and meta-analyses. Authors have used this guideline worldwide to prepare their reviews for publication. In the past, these reports typically compared 2 treatment alternatives. With the evolution of systematic reviews that compare multiple treatments, some of them only indirectly, authors face novel challenges for conducting and reporting their reviews. This extension of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) statement was developed specifically to improve the reporting of systematic reviews incorporating network meta-analyses. A group of experts participated in a systematic review, Delphi survey, and face-to-face discussion and consensus meeting to establish new checklist items for this extension statement. Current PRISMA items were also clarified. A modified, 32-item PRISMA extension checklist was developed to address what the group considered to be immediately relevant to the reporting of network meta-analyses. This document presents the extension and provides examples of good reporting, as well as elaborations regarding the rationale for new checklist items and the modification of previously existing items from the PRISMA statement. It also highlights educational information related to key considerations in the practice of network meta-analysis. The target audience includes authors and readers of network meta-analyses, as well as journal editors and peer reviewers. [ABSTRACT FROM AUTHOR]
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- 2015
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8. Dealing with substantial heterogeneity in Cochrane reviews. Cross-sectional study.
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Schroll, Jeppe B., Moustgaard, Rasmus, and Gøtzsche, Peter C.
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META-analysis ,MEDICAL research evaluation ,QUANTITATIVE research ,CROSS-sectional method ,HETEROGENEITY - Abstract
Background: Dealing with heterogeneity in meta-analyses is often tricky, and there is only limited advice for authors on what to do. We investigated how authors addressed different degrees of heterogeneity, in particular whether they used a fixed effect model, which assumes that all the included studies are estimating the same true effect, or a random effects model where this is not assumed. Methods: We sampled randomly 60 Cochrane reviews from 2008, which presented a result in its first meta-analysis with substantial heterogeneity (I² greater than 50%, i.e. more than 50% of the variation is due to heterogeneity rather than chance). We extracted information on choice of statistical model, how the authors had handled the heterogeneity, and assessed the methodological quality of the reviews in relation to this. Results: The distribution of heterogeneity was rather uniform in the whole I² interval, 50-100%. A fixed effect model was used in 33 reviews (55%), but there was no correlation between I² and choice of model (P = 0.79). We considered that 20 reviews (33%), 16 of which had used a fixed effect model, had major problems. The most common problems were: use of a fixed effect model and lack of rationale for choice of that model, lack of comment on even severe heterogeneity and of reservations and explanations of its likely causes. The problematic reviews had significantly fewer included trials than other reviews (4.3 vs. 8.0, P = 0.024). The problems became less pronounced with time, as those reviews that were most recently updated more often used a random effects model. Conclusion: One-third of Cochrane reviews with substantial heterogeneity had major problems in relation to their handling of heterogeneity. More attention is needed to this issue, as the problems we identified can be essential for the conclusions of the reviews. [ABSTRACT FROM AUTHOR]
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- 2011
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9. The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration.
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Liberati, Alessandro, Altman, Douglas G., Tetzlaff, Jennifer, Mulrow, Cynthia, Gøtzsche, Peter C., Ioannidis, John P. A., Clarke, Mike, Devereaux, P. J., Kleijnen, Jos, and Moher, David
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SYSTEMATIC reviews ,META-analysis ,EVALUATION of medical care ,MEDICAL research ,PUBLIC health ,HEALTH care intervention (Social services) - Abstract
Systematic reviews and meta-analyses are essential to summarize evidence relating to efficacy and safety of health care interventions accurately and reliably. The clarity and transparency of these reports, however, is not optimal. Poor reporting of systematic reviews diminishes their value to clinicians, policy makers, and other users. Since the development of the QUOROM (QUality Of Reporting Of Meta-analysis) Statement--a reporting guideline published in 1999--there have been several conceptual, methodological, and practical advances regarding the conduct and reporting of systematic reviews and meta-analyses. Also, reviews of published systematic reviews have found that key information about these studies is often poorly reported. Realizing these issues, an international group that included experienced authors and methodologists developed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) as an evolution of the original QUOROM guideline for systematic reviews and meta-analyses of evaluations of health care interventions. The PRISMA Statement consists of a 27-item checklist and a four-phase flow diagram. The checklist includes items deemed essential for transparent reporting of a systematic review. In this Explanation and Elaboration document, we explain the meaning and rationale for each checklist item. For each item, we include an example of good reporting and, where possible, references to relevant empirical studies and methodological literature. The PRISMA Statement, this document, and the associated Web site (www .prisma-statement.org) should be helpful resources to improve reporting of systematic reviews and meta-analyses. [ABSTRACT FROM AUTHOR]
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- 2009
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10. Overdiagnosis in publicly organised mammography screening programmes: systematic review of incidence trends.
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Jørgensen, Karsten Juhl and Gøtzsche, Peter C.
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DIAGNOSIS , *BREAST cancer , *MAMMOGRAMS , *REGRESSION analysis , *META-analysis , *CANCER in women , *MEDICAL screening - Abstract
Objective To estimate the extent of overdiagnosis (the detection of cancers that will not cause death or symptoms) in publicly organised screening programmes. Design Systematic review of published trends in incidence of breast cancer before and after the introduction of mammography screening. Data sources PubMed (April 2007), reference lists, and authors. Review methods One author extracted data on incidence of breast cancer (including carcinoma in situ), population size, screening uptake, time periods, and age groups, which were checked independently by the other author. Linear regression was used to estimate trends in incidence before and after the introduction of screening and in older, previously screened women. Meta-analysis was used to estimate the extent of overdiagnosis. Results Incidence data covering at least seven years before screening and seven years after screening had been fully implemented, and including both screened and non-screened age groups, were available from the United Kingdom; Manitoba, Canada; New South Wales, Australia; Sweden; and parts of Norway. The implementation phase with its prevalence peak was excluded and adjustment made for changing background incidence and compensatory drops in incidence among older, previously screened women. Overdiagnosis was estimated at 52% (95% confidence interval 46% to 58%). Data from three countries showed a drop in incidence as the women exceeded the age limit for screening, but the reduction was small and the estimate of overdiagnosis was compensated for in this review. Conclusions The increase in incidence of breast cancer was closely related to the introduction of screening and little of this increase was compensated for by a drop in incidence of breast cancer in previously screened women. One in three breast cancers detected in a population offered organised screening is overdiagnosed. [ABSTRACT FROM AUTHOR]
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- 2009
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11. Acupuncture treatment for pain: systematic review of randomised clinical trials with acupuncture, placebo acupuncture, and no acupuncture groups.
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Madsen, Matias Vested, Gøtzsche, Peter C., and Hróbjartsson, Asbjørn
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ACUPUNCTURE research , *PLACEBOS , *PAIN management , *CLINICAL trials , *META-analysis , *MEDICAL research - Abstract
Objectives To study the analgesic effect of acupuncture and placebo acupuncture and to explore whether the type of the placebo acupuncture is associated with the estimated effect of acupuncture. Design Systematic review and meta-analysis of three armed randomised clinical trials. Data sources Cochrane Library, Medline, Embase, Biological Abstracts, and PsycLIT. Data extraction and analysis Standardised mean differences from each trial were used to estimate the effect of acupuncture and placebo acupuncture. The different types of placebo acupuncture were ranked from 1 to 5 according to assessment of the possibility of a physiological effect, and this ranking was meta-regressed with the effect of acupuncture. Data synthesis Thirteen trials (3025 patients) involving a variety of pain conditions were eligible. The allocation of patients was adequately concealed in eight trials. The clinicians managing the acupuncture and placebo acupuncture treatments were not blinded in any of the trials. One clearly outlying trial (70 patients) was excluded. A small difference was found between acupuncture and placebo acupuncture: standardised mean difference -0.17 (95% confidence interval -0.26 to -0.08), corresponding to 4 mm (2 mm to 6 mm) on a 100 mm visual analogue scale. No statistically significant heterogeneity was present (P=0.10, I2=36%). A moderate difference was found between placebo acupuncture and no acupuncture: standardised mean difference -0.42 (-0.60 to -0.23). However, considerable heterogeneity (P<0.001, I2=66%) was also found, as large trials reported both small and large effects of placebo. No association was detected between the type of placebo acupuncture and the effect of acupuncture (P=0.60). Conclusions A small analgesic effect of acupuncture was found, which seems to lack clinical relevance and cannot be clearly distinguished from bias. Whether needling at acupuncture points, or at any site, reduces pain independently of the psychological impact of the treatment ritual is unclear. [ABSTRACT FROM AUTHOR]
- Published
- 2009
12. Industry-supported meta-analyses compared with meta-analyses with non-profit or no support: Differences in methodological quality and conclusions.
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Jørgensen, Anders W., Maric, Katja L., Tendal, Britta, Faurschou, Annesofie, and Gøtzsche, Peter C.
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CLINICAL drug trials ,META-analysis ,DISCLOSURE ,DECISION making in clinical medicine ,PHARMACEUTICAL industry - Abstract
Background: Studies have shown that industry-sponsored meta-analyses of drugs lack scientific rigour and have biased conclusions. However, these studies have been restricted to certain medical specialities. We compared all industry-supported meta-analyses of drug-drug comparisons with those without industry support. Methods: We searched PubMed for all meta-analyses that compared different drugs or classes of drugs published in 2004. Two authors assessed the meta-analyses and independently extracted data. We used a validated scale for judging the methodological quality and a binary scale for judging conclusions. We divided the meta-analyses according to the type of support in 3 categories: industry-supported, non-profit support or no support, and undeclared support. Results: We included 39 meta-analyses. Ten had industry support, 18 non-profit or no support, and 11 undeclared support. On a 0-7 scale, the median quality score was 6 for meta-analyses with non-profit or no support and 2.5 for the industry-supported meta-analyses (P < 0.01). Compared with industry-supported metaanalyses, more meta-analyses with non-profit or no support avoided bias in the selection of studies (P = 0.01), more often stated the search methods used to find studies (P = 0.02), searched comprehensively (P < 0.01), reported criteria for assessing the validity of the studies (P = 0.02), used appropriate criteria (P = 0.04), described methods of allocation concealment (P = 0.05), described methods of blinding (P = 0.05), and described excluded patients (P = 0.08) and studies (P = 0.15). Forty percent of the industry-supported meta-analyses recommended the experimental drug without reservations, compared with 22% of the meta-analyses with non-profit or no support (P = 0.57). In a sensitivity analysis, we contacted the authors of the meta-analyses with undeclared support. Eight who replied that they had not received industry funding were added to those with non-profit or no support, and 3 who did not reply were added to those with industry support. This analysis did not change the results much. Conclusion: Transparency is essential for readers to make their own judgment about medical interventions guided by the results of meta-analyses. We found that industry-supported meta-analyses are less transparent than meta-analyses with non-profit support or no support. [ABSTRACT FROM AUTHOR]
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- 2008
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13. Empirical Evidence for Selective Reporting of Outcomes in Randomized Trials: Comparison of Protocols to Published Articles.
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Chan, An-Wen, Hróbjartsson, Asbjørn, Haahr, Mette T., Gøtzsche, Peter C., and Altman, Douglas G.
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MEDICAL research evaluation ,MEDICAL journalism ,MEDICAL research personnel ,SURVEYS ,META-analysis ,COMMON misconceptions ,PREJUDICES ,STATISTICAL reliability ,HEALTH outcome assessment - Abstract
Context Selective reporting of outcomes within published studies based on the nature or direction of their results has been widely suspected, but direct evidence of such bias is currently limited to case reports. Objective To study empirically the extent and nature of outcome reporting bias in a cohort of randomized trials. Design Cohort study using protocols and published reports of randomized trials approved by the Scientific-Ethical Committees for Copenhagen and Frederiksberg, Denmark, in 1994-1995. The number and characteristics of reported and unreported trial outcomes were recorded from protocols, journal articles, and a survey of trialists. An outcome was considered incompletely reported if insufficient data were presented in the published articles for meta-analysis. Odds ratios relating the completeness of outcome reporting to statistical significance were calculated for each trial and then pooled to provide an overall estimate of bias. Protocols and published articles were also compared to identify discrepancies in primary outcomes. Main Outcome Measures Completeness of reporting of efficacy and harm outcomes and of statistically significant vs nonsignificant outcomes; consistency between primary outcomes defined in the most recent protocols and those defined in published articles. Results One hundred two trials with 122 published journal articles and 3736 outcomes were identified. Overall, 50% of efficacy and 65% of harm outcomes per trial were incompletely reported. Statistically significant outcomes had a higher odds of being fully reported compared with nonsignificant outcomes for both efficacy (pooled odds ratio, 2.4; 95% confidence interval [CI], 1.4-4.0) and harm (pooled odds ratio, 4.7; 95% CI, 1.8-12.0) data. In comparing published articles with protocols, 62% of trials had at least 1 primary outcome that was changed, introduced, or omitted. Eighty-six percent of survey responders (42/49) denied the existence of unreported outcomes despite clear... [ABSTRACT FROM AUTHOR]
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- 2004
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14. Disagreements in meta-analyses using outcomes measured on continuous or rating scales: observer agreement study.
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Tendal, Britta, Higgins, Julian P. T., Jüni, Peter, Hróbjartsson, Asbjørn, Trelle, Sven, Nüesch, Eveline, Wandel, Simon, Jørgensen, Anders W., Gesser, Katarina, Ilsøe-Kristensen, Søren, and Gøtzsche, Peter C.
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META-analysis ,STANDARDIZED tests ,DATA analysis ,CONFIDENCE intervals ,DATA extraction ,STANDARD deviations - Abstract
Objective To study the inter-observer variation related to extraction of continuous and numerical rating scale data from trial reports for use in meta-analyses. Design Observer agreement study. Data sources A random sample of 10 Cochrane reviews that presented a result as a standardised mean difference (SMD), the protocols for the reviews and the trial reports (n=45) were retrieved. Data extraction Five experienced methodologists and five PhD students independently extracted data from the trial reports for calculation of the first SMD result in each review. The observers did not have access to the reviews but to the protocols, where the relevant outcome was highlighted. The agreement was analysed at both trial and meta-analysis level, pairing the observers in all possible ways (45 pairs, yielding 2025 pairs of trials and 450 pairs of meta-analyses). Agreement was defined as SMDs that differed less than 0.1 in their point estimates or confidence intervals. Results The agreement was 53% at trial level and 31% at meta-analysis level. Including all pairs, the median disagreement was SMD=0.22 (interquartile range 0.07-0.61). The experts agreed somewhat more than the PhD students at trial level (61% v 46%), but not at meta-analysis level. Important reasons for disagreement were differences in selection of time points, scales, control groups, and type of calculations; whether to include a trial in the meta- analysis; and data extraction errors made by the observers. In 14 out of the 100 SMDs calculated at the meta-analysis level, individual observers reached different conclusions than the originally published review. Conclusions Disagreements were common and often larger than the effect of commonly used treatments. Meta-analyses using SMDs are prone to observer variation and should be interpreted with caution. The reliability of meta-analyses might be improved by having more detailed review protocols, more than one observer, and statistical expertise. [ABSTRACT FROM AUTHOR]
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- 2009
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15. Authors' reply on Cochrane reviews v industry supported meta-analyses.
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Jørgensen, Anders W., Gøtzsche, Peter C., and Hilden, Jørgen
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LETTERS to the editor , *META-analysis - Abstract
A response by Anders W. Jørgensen, Peter C. Gøtzsche, and Jørgen Hilden to a letter to the editor about their article "Cochrane reviews compared with industry supported meta-analyses and other meta-analyses of the same drugs: systematic review," in the October 14, 2006 issue is presented.
- Published
- 2006
16. General health checks in adults for reducing morbidity and mortality from disease: Cochrane systematic review and meta-analysis.
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Krogsbøll, Lasse T., Juhl Jørgensen, Karsten, Grønhøj Larsen, Christian, and Gøtzsche, Peter C.
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MEDICAL screening evaluation ,CONFIDENCE intervals ,META-analysis ,MORTALITY ,RESEARCH funding ,SYSTEMATIC reviews ,DESCRIPTIVE statistics - Abstract
The article reports a study which examined benefits and harms of general health checks in terms of outcomes relevant to patients. The study revealed that general health checks did not reduce morbidity or mortality, neither overall nor for cardiovascular or cancer causes, although they increased the number of new diagnoses. In the absence of benefits, the increased number of diagnoses with health checks suggests overdiagnosis and overtreatment.
- Published
- 2012
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