Abstract P274: A meta-analysis of meta-analyses: Is "reverse Epi" OK or not?

Circulation ◽  
2014 ◽  
Vol 129 (suppl_1) ◽  
Author(s):  
Ken Williams ◽  
Allan D Sniderman

Introduction: Applications of observational risk models assuming “all else equal” to estimate the effect on risk of interventions expected to change the level of one or more independent variables have been criticized as “reverse Epi” since clinical trials provide better estimates of treatment effects. Hypothesis: The purpose of this analysis is to assess how reasonable it is to use “reverse Epi” to project the number of events avoided under different scenarios in which different markers are used for determining to whom to prescribe and how to target preventative treatment. We pursued this aim by comparing two different meta-analyses which compared HRs for apoB and non-HDL-C. One meta-analysis included 12 published observational studies. In 11 of these studies all subjects were at primary CHD risk. The other meta-analysis included 7 placebo-controlled statin trials (3 primary and 4 secondary). Methods: We calculated the reciprocal of each observational study’s HR per 1-SD increase (36 mg/dl for non-HDL-C and 27 mg/dl of apoB) to compare with each trials’ HR per 1-SD decrease; calculated the percentage difference (95% CI) in standard HRs for each report assuming a correlation between the two markers of 0.93 (calculated from NHANES 2005-2010 to be representative of adult US residents); and compared the resulting statistics using standard subgroup meta-analysis. Results: The overall geometric mean point estimate (95% CI) of the difference favoring apoB over non-HDL-C for all observational studies was 11.1% (7.7%, 14.4%) versus 5.4% (2.9%, 9.2%) for all 7 trials (p = 0.007). However these same point estimates are 9.5% (7.3%, 14.0%) versus 10.6% (7.3%, 14.0%) (p=0.714) when only primary studies or trials were included. The geometric mean treatment effect HR among the 4 secondary trials was 0.732 (0.689, 0.792) versus 0.599 (0.504, 0.714) among the 3 primary trials (p = 0.035). Conclusion: Meaningful differences between primary and secondary observational and interventional studies warrant stratified analysis. Among subjects at primary CHD risk, “reverse Epi” application of primary observational results may provide projections similar to those from applying primary trial results.

2016 ◽  
Vol 26 (4) ◽  
pp. 364-368 ◽  
Author(s):  
P. Cuijpers ◽  
E. Weitz ◽  
I. A. Cristea ◽  
J. Twisk

AimsThe standardised mean difference (SMD) is one of the most used effect sizes to indicate the effects of treatments. It indicates the difference between a treatment and comparison group after treatment has ended, in terms of standard deviations. Some meta-analyses, including several highly cited and influential ones, use the pre-post SMD, indicating the difference between baseline and post-test within one (treatment group).MethodsIn this paper, we argue that these pre-post SMDs should be avoided in meta-analyses and we describe the arguments why pre-post SMDs can result in biased outcomes.ResultsOne important reason why pre-post SMDs should be avoided is that the scores on baseline and post-test are not independent of each other. The value for the correlation should be used in the calculation of the SMD, while this value is typically not known. We used data from an ‘individual patient data’ meta-analysis of trials comparing cognitive behaviour therapy and anti-depressive medication, to show that this problem can lead to considerable errors in the estimation of the SMDs. Another even more important reason why pre-post SMDs should be avoided in meta-analyses is that they are influenced by natural processes and characteristics of the patients and settings, and these cannot be discerned from the effects of the intervention. Between-group SMDs are much better because they control for such variables and these variables only affect the between group SMD when they are related to the effects of the intervention.ConclusionsWe conclude that pre-post SMDs should be avoided in meta-analyses as using them probably results in biased outcomes.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Ossama Abdelraoof El Shazly ◽  
Mohamed Mokhtar Abdellah ◽  
Mostafa Abdelnabee Abouzaid

Abstract Background With continued loss of dorsiflexion of the 1st MTP, degenerative changes occur within the joint with severe restriction of movement and increase in pain, which leads to the condition known as hallux rigidus. The amount of dorsiflexion may be reduced to 0-10 degrees with pain on both active and passive motion. Objectives Systematically reviewing available evidence from published articles to assess the effectiveness of arthrodesis of first metatarsophalangeal joint by plate and screws in hallux rigidus. The assessment also would encompass safety, side effects, and complications of this mode of treatment. Materials and Methods We performed this systematic review and meta-analysis in accordance to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and Meta-analysis Of Observational Studies in Epidemiology (MOOSE) statement. PRISMA and MOOSE are reporting checklists for Authors, Editors, and Reviewers of Meta-analyses of interventional and observational studies. According to International committee of medical journal association (ICJME), reviewers must report their findings according to each of the items listed in those checklists. Results Previous results for arthrodesis have been favourable with a union rate of almost 96%. In the present systematic review and meta-analysis, the overall effect estimates showed that the union rates after plate and screw arthrodesis for 1st MTPJ was 96.2% (95% CI 94 – 98.4%). In addition, the overall effect estimates showed that the non-union rates after plate and screw arthrodesis for 1st MTPJ was 4.2% (95% CI 2.4 – 6.1%). Moreover, the overall effect estimates showed that the satisfaction rates after plate and screw arthrodesis for 1st MTPJ was 94.5% (95% CI 90 – 99%). In the present study, the overall effect estimates showed that the overall complications rate after plate and screw arthrodesis for 1st MTPJ was 7.2% (95% CI 2.5 – 12%). The overall effect estimates showed that the malunion rates after plate and screw arthrodesis for 1st MTPJ was 2.7% (95% CI 0 – 6.4%). Additionally, the overall effect estimates showed that the hardware removal and superficial infection rates after plate and screw arthrodesis for 1st MTPJ were 2% and 2.9%, respectively. Conclusion Our analysis showed that plate and screws fixation is effective techniques that can be used for first MTPJ arthrodesis in patients with hallux rigidus. We found that the screw and plate fixation has a significantly lower rate of nonunion compared with the screw alone, as reported by the literature. However, owing to the small group sizes and methodologic shortcomings, we were unable to identify the clinically superior fixation technique for first MTPJ arthrodesis arthrodesis.


2015 ◽  
Vol 114 (9) ◽  
pp. 1341-1359 ◽  
Author(s):  
Míriam Rodríguez-Monforte ◽  
Gemma Flores-Mateo ◽  
Emília Sánchez

AbstractEpidemiological studies show that diet is linked to the risk of developing CVD. The objective of this meta-analysis was to estimate the association between empirically derived dietary patterns and CVD. PubMed was searched for observational studies of data-driven dietary patterns that reported outcomes of cardiovascular events. The association between dietary patterns and CVD was estimated using a random-effects meta-analysis with 95 % CI. Totally, twenty-two observational studies met the inclusion criteria. The pooled relative risk (RR) for CVD, CHD and stroke in a comparison of the highest to the lowest category of prudent/healthy dietary patterns in cohort studies was 0·69 (95 % CI 0·60, 0·78; I2=0 %), 0·83 (95 % CI 0·75, 0·92; I2=44·6 %) and 0·86 (95 % CI 0·74, 1·01; I2=59·5 %), respectively. The pooled RR of CHD in a case–control comparison of the highest to the lowest category of prudent/healthy dietary patterns was 0·71 (95 % CI 0·63, 0·80; I2=0 %). The pooled RR for CVD, CHD and stroke in a comparison of the highest to the lowest category of western dietary patterns in cohort studies was 1·14 (95 % CI 0·92, 1·42; I2=56·9 %), 1·03 (95 % CI 0·90, 1·17; I2=59·4 %) and 1·05 (95 % CI 0·91, 1·22; I2=27·6 %), respectively; in case–control studies, there was evidence of increased CHD risk. Our results support the evidence of the prudent/healthy pattern as a protective factor for CVD.


Author(s):  
C Dandurand ◽  
AA Sepehry ◽  
MH Asadi Lari ◽  
R Akagami ◽  
PA Gooderham

Background: The optimal therapeutic approach for adult craniopharyngioma remains controversial. Some advocate for gross total resection (GTR), while others support subtotal resection followed by adjuvant radiotherapy (STR + XRT). Methods: MEDLINE (1946 to July 1st 2016) and EMBASE (1980 to June 30th 2016) were systematically reviewed. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed. At our institution, from 1975 to 2013, 33 patients were treated with initial surgical resection for adult onset craniopharyngioma. 22 patients were included in the present case series. Results: Eligible studies (n=21) were identified from the literature in addition to a case series of our institutional experience. Three groups were available for analysis: GTR, STR + XRT, and STR. The rates of recurrence were 17 %, 27 % and 45%, respectively. This differs from childhood population. The difference in risk of recurrence after GTR vs. STR + XRT did not reach significance (OR: 0.63, 95% confidence interval: 0.33-1.24, P=0.18). This maybe because of low pooled sample size (n=99) who underwent STR+XRT. Conclusions: This is the first and largest meta-analysis examining rate of recurrence in adult craniopharyngioma. Thus, when safe and feasible, a goal of gross total resection should be favored. Each patient should be considered on a case-by-case basis.


2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Kwuntida Uthaisar Kotepui ◽  
Manas Kotepui

Abstract Background Plasmodium spp. and hepatitis B virus (HBV) are among the most common infectious diseases in underdeveloped countries. This study aimed to determine the prevalence of Plasmodium spp. and HBV co-infection in people living in endemic areas of both diseases and to assess the risk factors related to this co-infection. Methods The PubMed, Web of Science, and Scopus databases were searched. Observational cross-sectional studies and retrospective studies assessing the prevalence of Plasmodium species and HBV co-infection were examined. The methodological quality of the included studies was assessed with the Newcastle-Ottawa Scale (NOS), a tool for assessing the quality of nonrandomized studies in meta-analyses, and heterogeneity among the included studies was assessed with Cochran's Q test and the I2 (inconsistency) statistic. The pooled prevalence of the co-infection and its 95% confidence interval (CI) were estimated using the random-effects model, depending on the amount of heterogeneity there was among the included studies. The pooled odds ratio (OR) represented the difference in qualitative variables, whereas the pooled mean difference (MD) represented the difference in quantitative variables. Meta-analyses of the potential risk factors for Plasmodium spp. and HBV co-infection, including patient age and gender, were identified and represented as pooled odds ratios (OR) and 95% CIs. Publication bias among the included studies was assessed by visual inspection of a funnel plot to search for asymmetry. Results Twenty-two studies were included in the present systematic review and meta-analysis. Overall, the pooled prevalence estimate of Plasmodium spp. and HBV co-infection was 6% (95% CI 4–7%, Cochran's Q statistic < 0.001, I2: 95.8%), with prevalences of 10% in Gambia (95% CI: 8–12%, weight: 4.95%), 8% in Italy (95% CI 5–12%, weight: 3.8%), 7% in Nigeria (95% CI 4–10%, weight: 53.5%), and 4% in Brazil (95% CI 2–5%, weight: 19.9%). The pooled prevalence estimate of Plasmodium spp. and HBV co-infection was higher in studies published before 2015 (7%, 95% CI 4–9%, Cochran's Q statistic < 0.001, I2: 96%) than in those published since 2015 (3%, 95% CI 1–5%, Cochran's Q statistic < 0.001, I2: 81.3%). No difference in age and risk of Plasmodium spp. and HBV co-infection group was found between the Plasmodium spp. and HBV co-infection and the Plasmodium monoinfection group (p: 0.48, OR: 1.33, 95% CI 0.60–2.96). No difference in gender and risk of Plasmodium spp. and HBV co-infection group was found between the Plasmodium spp. and HBV co-infection and HBV co-infection group and the Plasmodium monoinfection group (p: 0.09, OR: 2.79, 95% CI 0.86–9.10). No differences in mean aspartate aminotransferase (AST), mean alanine aminotransferase (ALT), or mean total bilirubin levels were found (p > 0.05) between the Plasmodium spp. and HBV co-infection group and the Plasmodium monoinfection group. Conclusions The present study revealed the prevalence of Plasmodium spp. and HBV co-infection, which will help in understanding co-infection and designing treatment strategies. Future studies assessing the interaction between Plasmodium spp. and HBV are recommended.


2020 ◽  
pp. 019459982095796
Author(s):  
Claudia I. Cabrera ◽  
Alexander Joseph Jones ◽  
Noah Philleo Parker ◽  
Amy Emily Lynn Blevins ◽  
Mark S. Weidenbecher

Objective To evaluate the difference in pharygocutaneous fistula (PCF) development between pectoralis major flap onlay and interpositional reconstructions after salvage total laryngectomy (STL). Data Sources Medline, Cochrane, Embase, Web of Science, CINAHL, and ClinicalTrials.gov. Review Methods A systematic review was performed during January 2020. English articles were included that described minor and major PCF rates after STL reconstructed with pectoralis major onlay or interposition. PCFs were classified as major when conservative therapy was unsuccessful and/or revision surgery was needed. Articles describing total laryngopharyngectomies were excluded. Meta-analyses of the resulting data were performed. Results Twenty-four articles met final criteria amassing 1304 patients. Three articles compared onlay with interposition, and 18 compared onlay with primary closure. Pectoralis interposition demonstrated elevated odds ratio (OR) of PCF formation as compared with onlay (OR, 2.34; P < .001). Onlay reconstruction reduced overall (OR, 0.32; P < .001) and major (OR, 0.21; P < .001) PCF development as compared with primary pharyngeal closure alone. Data were insufficient to compare interposition against primary closure. Conclusions This research shows evidence that pectoralis onlay after STL diminishes the odds of total and major PCF development. Pectoralis interposition reconstruction showed elevated odds of PCF formation as compared with pectoralis onlay.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Satoshi Ida ◽  
Ryutaro Kaneko ◽  
Kanako Imataka ◽  
Kazuya Murata

Previous studies involving patients with diabetes have indicated that sarcopenia is related to renal function. The objective of the present study was to investigate the association between sarcopenia and urinary albumin level, urinary protein level, and estimated glomerular filtration rate (eGFR) in patients with diabetes. A meta-analysis of observational studies was conducted. A literature search was performed using MEDLINE, Cochrane Controlled Trials Registry, and ClinicalTrials.gov. Data were extracted from studies investigating the association between sarcopenia and urinary albumin level, urinary protein level, and eGFR and by calculating odds ratio (OR) and 95% confidence intervals (CIs). Statistical analysis was performed using a random-effects model to calculate pooled OR and 95% CI. Six studies (2662 patients) that met the criteria were included in the meta-analysis. Sarcopenia was significantly associated with urinary albumin level with a pooled OR of 2.11 (95% CI, 1.55–2.88; P<0.001). The pooled ORs of the associations between sarcopenia and urinary protein level and decreased eGFR were 1.82 (95% CI, 1.13–2.92; P=0.01) and 3.75 (95% CI, 1.24–11.41), respectively. Sarcopenia was significantly associated with urinary albumin level, urinary protein level, and decreased eGFR. However, further investigations are needed, including meta-analyses with a larger number of studies.


2019 ◽  
Vol 78 (6) ◽  
pp. 474-485 ◽  
Author(s):  
Jeffery L Heileson

Abstract The American Heart Association (AHA) recently published a meta-analysis that confirmed their 60-year-old recommendation to limit saturated fat (SFA, saturated fatty acid) and replace it with polyunsaturated fat to reduce the risk of heart disease based on the strength of 4 Core Trials. To assess the evidence for this recommendation, meta-analyses on the effect of SFA consumption on heart disease outcomes were reviewed. Nineteen meta-analyses addressing this topic were identified: 9 observational studies and 10 randomized controlled trials. Meta-analyses of observational studies found no association between SFA intake and heart disease, while meta-analyses of randomized controlled trials were inconsistent but tended to show a lack of an association. The inconsistency seems to have been mediated by the differing clinical trials included. For example, the AHA meta-analysis only included 4 trials (the Core Trials), and those trials contained design and methodological flaws and did not meet all the predefined inclusion criteria. The AHA stance regarding the strength of the evidence for the recommendation to limit SFAs for heart disease prevention may be overstated and in need of reevaluation.


2020 ◽  
pp. e1-e17
Author(s):  
Richard J. Wang ◽  
Sudhamayi Bhadriraju ◽  
Stanton A. Glantz

Objectives. To determine the association between e-cigarette use and smoking cessation. Methods. We searched PubMed, Web of Science Core Collection, and EMBASE and computed the association of e-cigarette use with quitting cigarettes using random effects meta-analyses. Results. We identified 64 papers (55 observational studies and 9 randomized clinical trials [RCTs]). In observational studies of all adult smokers (odds ratio [OR] = 0.947; 95% confidence interval [CI] = 0.772, 1.160) and smokers motivated to quit smoking (OR = 0.851; 95% CI = 0.684, 1.057), e-cigarette consumer product use was not associated with quitting. Daily e-cigarette use was associated with more quitting (OR = 1.529; 95% CI = 1.158, 2.019) and less-than-daily use was associated with less quitting (OR = 0.514; 95% CI = 0.402, 0.665). The RCTs that compared quitting among smokers who were provided e-cigarettes to smokers with conventional therapy found e-cigarette use was associated with more quitting (relative risk = 1.555; 95% CI = 1.173, 2.061). Conclusions. As consumer products, in observational studies, e-cigarettes were not associated with increased smoking cessation in the adult population. In RCTs, provision of free e-cigarettes as a therapeutic intervention was associated with increased smoking cessation. Public Health Implications. E-cigarettes should not be approved as consumer products but may warrant consideration as a prescription therapy. (Am J Public Health. Published online ahead of print December 22, 2020: e1–e17. https://doi.org/10.2105/AJPH.2020.305999 )


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Qiang Li ◽  
Ying Liu ◽  
Hong-Mei Zhang ◽  
Yin-Peng Huang ◽  
Tian-Yi Wang ◽  
...  

Our meta-analysis aggregated existing results from relevant studies to comprehensively investigate the correlations between genetic polymorphisms in dihydropyrimidine dehydrogenase (DPYD) gene and 5-fluorouracil (5-FU) toxicities in patients with colorectal cancer (CRC). The MEDLINE (1966∼2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980∼2013), CINAHL (1982∼2013), Web of Science (1945∼2013), and the Chinese Biomedical Database (CBM) (1982∼2013) were searched without language restrictions. Meta-analyses were conducted with the use of STATA software (Version 12.0, Stata Corporation, College Station, TX, USA). Seven clinical cohort studies with a total of 946 CRC patients met our inclusion criteria, and NOS scores of each of the included studies were ≥5. Our findings showed thatDPYDgenetic polymorphisms were significantly correlated with high incidences of 5-FU-related toxicity in CRC patients. SNP-stratified analysis indicated that there were remarkable connections of IVS14+1G>A, 464T>A, and 2194G>A polymorphisms with the incidence of marrow suppression in CRC patients receiving 5-FU chemotherapy. Furthermore, we found that IVS14+1G>A, 496A>G, and 2194G>A polymorphisms were correlated with the incidence of gastrointestinal reaction. Ethnicity-stratified analysis also revealed thatDPYDgenetic polymorphisms might contribute to the development of marrow suppression and gastrointestinal reaction among Asians, but not among Caucasians. The present meta-analysis suggests thatDPYDgenetic polymorphisms may be correlated with the incidence of 5-FU-related toxicity in CRC patients.


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