Antibiotics for eradicating meningococcal carriages: Network meta-analysis and investigation of evidence inconsistency

AIM

To compare different antibiotics for eradicating the carriage of Neisseria meningitidis (N. meningitidis), and to investigate heterogeneity and evidence inconsistency.

METHODS

From a search of PubMed and published systematic reviews, we identified 23 trials evaluating 15 antibiotics that could be connected in a trial network. The outcome of interest is the eradication of N. meningitidis. We used WinBUGS to conduct random-effects, mixed treatment comparisons. Heterogeneity and evidence inconsistency was investigated by meta-regression modelling and examining characteristics of trial participants and interventions evaluated.

RESULTS

Rifampin, ciprofloxacin, minocycline, ceftriaxone, and azythromycin were statistically significantly (P < 0.05) more effective than placebo. The probability of being the best was 67.0% for a combination of rifampin and minocycline, 25.0% for ceftriaxone, 1.7% for azythromycin, and below 1% for the remaining regimens. Significant inconsistency between the direct and indirect estimates was observed for the comparison of rifampin and ciprofloxacin (P < 0.01), which may be caused by different types of carriers and different doses of ciprofloxacin.

CONCLUSION

A range of prophylactic antibiotic regimens are effective for eradicating meningococcal carriages, and treatment choice will depend on the individual priorities of the patients and physicians. In clinical situations where complete eradication is considered to be of the utmost importance, a combination of rifampin and minocycline seems to offer the highest likelihood of success. Ceftriaxone as a single intramuscular injection is also likely to be more effective as compared with the other two antibiotics (ciprofloxacin or rifampin) recommended by the current guidelines.

Efficacy, safety, and dose comparison of degarelix for the treatment of prostate cancer: A systematic review and meta-analysis

AIM: To conduct a systematic review and meta-analysis into the efficacy, safety, and dosage regimens of degarelix for treating prostate cancer (PCa).

METHODS: PubMed, EMBASE, the Cochrane Library, and Web of Science was systematically searched to identify randomized controlled trials (RCTs) comparing degarelix (240/80 mg vs 240/160 mg) to the gonadotropin-releasing hormone agonists, goserelin and leuprolide, for the treatment of PCa. Two independent reviewers screened putative studies, assessed the risk of bias, and then extracted pertinent data. Analyses were performed using Review Manager 5.2.

RESULTS: Seven papers from six RCTs, involving 1204 patients, were identified. The present meta-analysis showed that treatment with 240/160 mg degarelix is more effective and has fewer adverse events (AEs) relative to conventional 240/80 mg regimen. Degarelix significantly decreased International Prostate Symptom Scores [standardized mean differences (SMD) = -0.32, 95%CI: -0.51 to -0.12, P = 0.02] and caused fewer AEs (SMD = -0.28, 95%CI: -0.48 to -0.07, P = 0.008) than goserelin. Degarelix suppressed testosterone and prostate-specific antigen significantly faster than leuprolide.

CONCLUSION: Degarelix is a useful option in the treatment of advanced PCa. Degarelix 240/160 mg regimen was superior to a 240/80 mg regimen. More rigorously designed RCTs are urgently needed to confirm the efficacy of degarelix.

Helicobacter pylori infection and asthma: Is there a direct or an inverse association? A meta-analysis

AIM: To analyze the consistency of a potential involvement of the bacterium infection in the asthma disease.

METHODS: A systematic literature search of the terms “Helicobacter pylori” (H. pylori) associated to “asthma” using PubMed, Scopus and the Cochrane Library Central was performed. Reference lists from published articles were also employed. Titles of these publications and their abstracts were scanned in order to eliminate duplicates and irrelevant articles. The criteria of inclusion of the studies were: Original studies; the H. pylori diagnostic method has been declared; all ranges of age have been included in our study; a definitive diagnosis of asthma has been reported.

RESULTS: We selected 14 articles in which the association between the two conditions was addressed. In 7 studies the prevalence of H. pylori infection in the asthma population and in the control population was made explicit. There was heterogeneity between the studies (Cohran’s Q = 0.02). The H. pylori infection in the asthma population resulted 33.6% (518 of 1542), while in the control population resulted 37.6% (2746 of 7310) (relative risk of H. pylori infection in the asthma population = 0.87, 95%CI: 0.72-1.05, P = 0.015, random effects model). Instead, considering the more virulent strains, the majority of studies showed an inverse relationship between the prevalence of H. pylori infection and asthma.

CONCLUSION: In our meta-analysis the prevalence of H. pylori infection in the asthma population resulted not statistically significant lower than in control population (P = 0.15). Instead, considering the more virulent strains, the majority of studies showed an inverse relationship between the prevalence of H. pylori infection and asthma.

Environmental tobacco smoke exposure and lung cancer: A systematic review

AIM: To review evidence relating passive smoking to lung cancer risk in never smokers, considering various major sources of bias.

METHODS: Epidemiological prospective or case-control studies were identified which provide estimates of relative risk (RR) and 95%CI for never smokers for one or more of seven different indices of exposure to environmental tobacco smoke (ETS): The spouse; household; workplace; childhood; travel; social and other; and total. A wide range of study details were entered into a database, and the RRs for each study, including descriptions of the comparisons made, were entered into a linked database. RRs were derived where necessary. Results were entered, where available, for all lung cancer, and for squamous cell cancer and adenocarcinoma. “Most adjusted” results were entered based on results available, adjusted for the greatest number of potential confounding variables. “Least adjusted” results were also entered, with a preference for results adjusted at least for age for prospective studies. A pre-planned series of fixed-effects and random-effects meta-analyses were conducted. Overall analyses and analyses by continent were run for each exposure index, with results for spousal smoking given by sex, and results for childhood exposure given by source of ETS exposure. For spousal exposure, more extensive analyses provide results by various aspects of study design and definition of the RR. For smoking by the husband (or nearest equivalent), additional analyses were carried out both for overall risk, and for risk per 10 cigarettes per day smoked by the husband. These adjusted for uncontrolled confounding by four factors (fruit, vegetable and dietary fat consumption, and education), and corrected for misclassification of smoking status of the wife. For the confounding adjustment, estimates for never smoking women were derived from publications on the relationship of the four factors to both lung cancer risk and at home ETS exposure, and on the correlations between the factors. The bias due to misclassification was calculated on the basis that the proportion of ever smokers denying smoking is 10% in Asian studies and 2.5% elsewhere, and that those who deny smoking have the same risk as those who admit it. This approach, justified in previous work, balances higher true denial rates and lower risk in deniers compared to non-deniers.

RESULTS: One hundred and two studies were identified for inclusion, published in 1981 onwards, 45 in Asia, 31 in North America, 21 in Europe, and five elsewhere. Eighty-five were of case-control design and 17 were prospective. Significant (P < 0.05) associations were noted, with random-effects of (RR = 1.22, 95%CI: 1.14-1.31, n = 93) for smoking by the husband (RR = 1.14, 95%CI: 1.01-1.29, n = 45) for smoking by the wife (RR = 1.22, 95%CI: 1.15-1.30, n = 47) for workplace exposure (RR = 1.15, 95%CI: 1.02-1.29, n = 41) for childhood exposure, and (RR = 1.31, 95%CI: 1.19-1.45, n = 48) for total exposure. No significant association was seen for ETS exposure in travel (RR = 1.34, 95%CI: 0.94-1.93, n = 8) or in social situations (RR = 1.01, 95%CI: 0.82-1.24, n = 15). A significant negative association (RR = 0.78, 95%CI: 0.64-0.94, n = 8) was seen for ETS exposure in childhood, specifically from the parents. Significant associations were also seen for spousal smoking for both squamous cell carcinoma (RR = 1.44, 95%CI: 1.15-1.80, n = 24) and adenocarcinoma (RR = 1.33, 95%CI: 1.17-1.51, n = 30). Results generally showed marked heterogeneity between studies. For smoking by either the husband or wife, where 119 RR estimates gave an overall estimate of (RR = 1.21, 95%CI: 1.14-1.29), the heterogeneity was highly significant (P < 0.001), with evidence that the largest RRs were seen in studies published in 1981-89, in small studies (1-49 cases), and for estimates unadjusted by age. For smoking by the husband, the additional analyses showed that adjustment for the four factors reduced the overall (RR = 1.22, 95%CI: 1.14-1.31) based on 93 estimates to (RR = 1.14, 95%CI: 1.06-1.22), implying bias due to uncontrolled confounding of 7%. Further correction for misclassification reduced the estimate to a marginally non-significant (RR = 1.08, 95%CI: 0.999-1.16). In the fully adjusted and corrected analyses, there was evidence of an increase in Asia (RR = 1.18, 95%CI: 1.07-1.30, n = 44), but not in other regions (RR = 0.96, 95%CI: 0.86-1.07, n = 49). Studies published in the 1980’s, studies providing dose-response data, and studies only providing results unadjusted for age showed elevated RRs, but later published studies, studies not providing dose-response data, and studies adjusting for age did not. The pattern of results for RRs per 10 cigs/d was similar, with no significant association in the adjusted and corrected results (RR = 1.03, 95%CI: 0.994-1.07).

CONCLUSION: Most, if not all, of the ETS/lung cancer association can be explained by confounding adjustment and misclassification correction. Any causal relationship is not convincingly demonstrated.

Computed tomography fluoroscopy guided percutaneous lung biopsy for ground-glass opacity pulmonary lesions: A meta-analysis

AIM: To obtain the diagnostic performance of percutaneous transthoracic needle biopsy (PTNB) under Computed tomography (CT) fluoroscopy guidance for lung ground-glass opacity (GGO).

METHODS: We searched for English- and Chinese-language studies in PubMed, EMBASE, EBSCO, OVID, and CNKI (China National Knowledge Infrastructure) database. Data were calculated with Meta-Disc version 1.4 and Rev Man version 5.2 software. From the pooled data, we calculated sensitivity (Sen), specificity (Spe), positive likelihood ratio (+LR), negative likelihood ratio (-LR), and diagnostic odds ratio (DOR). Summary receiver operating characteristic (SROC) curves were constructed and incidence of complications was recorded.

RESULTS: Four documents included in this present meta-analysis met the criteria for analysis. The pooled Sen, Spe, +LR, -LR and DOR with 95%CI were 0.91 (0.86-0.95), 1.0 (0.91-1.0), 18.64 (4.83-71.93), 0.11 (0.05-0.26) and 153.17 (30.78-762.33), respectively. The area under the SROC curve was 0.98. The incidence of pneumothorax and hemoptysis was 17.86%-51.80% and 10.50%-19.40%, respectively.

CONCLUSION: CT fluoroscopy-guided PTNB, which has an acceptable incidence of complications, can be used as a primary examination method for lung GGO, with moderate sensitivity and specificity.

Meta-analysis comparing differing methods of endoscopic therapy for colorectal lesions

AIM: To compare the outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) of colorectal lesions.

METHODS: An electronic systematic literature search of four computerized databases was performed in July 2014 identifying studies reporting the outcomes of colorectal ESD and EMR. The primary outcome measures were en-bloc resection rate, endoscopic clearance rate and lesion recurrence rate of the patients followed up. The secondary outcome was the complication rate (including bleeding, perforation and surgery post EMR or ESD rate). Statistical pooling and random effects modelling of the studies calculating risk difference, heterogeneity and assessment of bias and quality were performed.

RESULTS: Six observational studies reporting the outcomes of 1324 procedures were included. The en-bloc resection rate was 50% higher in the ESD group than in the EMR group (95%CI: 0.17-0.83, P < 0.0001, I² = 99.7%). Endoscopic clearance rates were also significantly higher in the ESD group (95%CI: -0.06-0.02, P < 0.0001, I² = 92.5%). The perforation rate was 7% higher in the ESD group than the EMR group (95%CI: 0.05-0.09, P > 0.05, I² = 41.1%) and the rate of recurrence was 50% higher in the EMR group than in the ESD group (95%CI: 0.20-0.79, P < 0.001, I² = 99.5%). Heterogeneity remained consistent when subgroup analysis of high quality studies was performed (with the exception of piecemeal resection rate), and overall effect sizes remained unchanged for all outcomes.

CONCLUSION: ESD demonstrates higher en-bloc resection rates and lower recurrence rates compared to colorectal EMR. Differences in outcomes may benefit from increased assessment through well-designed comparative studies.

Expression of epithelial cellular adhesion molecule in gastric cancer: A meta-analysis

AIM: To obtain an accurate evaluation of the association between high expression of epithelial cellular adhesion molecule (EpCAM) and gastric cancer (GC) risk.

METHODS: Studies that had examined the association between high expression of EpCAM and GC risk were identified by searching electronic databases PubMed, EMBASE, Cochrane library and Chinese Biomedical Literature database. Risk ratios (RRs) together with their 95%CIs were used to assess the association between high expression of EpCAM and GC risk. We selected eligible studies based on inclusion criteria. RevMan 5.3 software was used to calculate the pooled values.

RESULTS: A total of 14 studies were included in this meta-analysis. EpCAM-positive cases were significantly associated with tumor size (RR: 1.68, 95%CI: 1.47-1.91, P < 0.00001 fixed-effect), depth of invasion (RR: 1.37, 95%CI: 1.11-1.68, P = 0.003 random-effect), TNM stage (RR: 2.02, 95%CI: 1.35-3.02, P = 0.0007 random-effect), tumor location (RR: 0.80, 95%CI: 0.71-0.91, P = 0.0007 fixed-effect), histologic differentiation (RR: 1.23, 95%CI: 1.13-1.33, P < 0.00001 fixed-effect) and lymph node metastasis (RR: 1.89, 95%CI: 1.28-2.80, P = 0.001 random-effect). However, we did not observe any significant association between the presence of EpCAM with age, gender, distant metastasis, Borrmann type or Lauren classification. Additionally, EpCAM expression was not associated with the overall survival rate. The pooled HR of the overall effect was 1.39 (95%CI: 0.30-6.48, P = 0.67 random-effect).

CONCLUSION: Our meta-analysis indicates that EpCAM contributes to GC risk, which acts as a prognostic factor and a marker of poor outcome.

Role of self-expanding metal stents in patients with malignant colorectal obstruction: A systematic review and meta-analysis

AIM: To assess the safety and efficacy of self-expandable metal stents (SEMSs) for malignant colorectal obstruction.

METHODS: Data regarding technical success, clinical success, and procedure related complications were collected from included studies. DerSimonian-Laird random effects model was used to generate the overall outcome. Thirty international studies with a total of 2058 patients with malignant colorectal obstruction were included.

RESULTS: The technical and clinical success rates for SEMS placement were 94% (95%CI: 92-96) and 91% (95%CI: 88-93), respectively. Overall complication rate for SEMS was 23% (95%CI: 18-29). Stent migration 8% (95%CI: 6-10) and stent obstruction 8% (95%CI: 6-11) were the most common complications, followed by perforation 5% (95%CI: 4%-7%). Surgical or endoscopic re-interventions were needed in 14% (95%CI: 10-18) of patients. Endoscopic repeat stent placement was required in 8% (95%CI: 6-10), while surgical intervention was needed in 6% (95%CI: 4-8).

CONCLUSION: SEMS are effective when used as palliation or bridge to surgery for malignant colorectal obstruction with high technical and clinical success. About 14% of patients require repeat endoscopic or surgical intervention for stent failure or to manage stent related complications.

Risk of pancreatic adverse events associated with the use of glucagon-like peptide-1 receptor agonist and dipeptidyl peptidase-4 inhibitor drugs: A systematic review and meta-analysis of randomized trials

AIM: To systematically assess risk of pancreatic adverse events with glucagon-like peptide-1 (GLP-1) receptor agonist and dipeptidyl peptidase-4 (DPP-4) inhibitor drugs.

METHODS: We searched PubMed, Embase, CINAHL, Cochrane review of clinical trials, pharmaceutical company clinical trials register, United States Food and Drug Administration website, European Medicines Agency website and ClinicalTrials.gov for randomized controlled trials from inception to October 2013. Randomized control trial studies were selected for inclusion if they reported on pancreatic complication events and/or changes in pancreatic enzyme levels (serum amylase and serum lipase) as adverse events or as serious adverse events for patients who were on GLP-1 receptor agonist and DPP-4 inhibitor drugs. Two independent reviewers extracted data directly. We performed Peto odds ratio (OR) fixed effect meta-analysis of pancreatic adverse events a, and assessed heterogeneity with the I² statistic.

RESULTS: Sixty-eight randomized controlled trials were eligible. A total of 60720 patients were included in our analysis of the association of risk of pancreatic complication events with GLP-1 agents. A total of 89 pancreatic related adverse events occurred among the GLP-1 agents compared to 74 events among the controls. There was a statistically significant increased risk of elevation of pancreatic enzymes associated with GLP-1 agents compared with control (Peto OR = 3.15, 95%CI: 1.56-6.39, P = 0.001, I² = 0%). There was no statistically significant difference in the risk of pancreatic adverse event associated with GLP-1 agent compared with controls (Peto OR = 1.00, 95%CI: 0.73-1.37, P = 1.00, I² = 0%). There were a total of 71 pancreatitis events in patients on GLP-1 agents and 56 pancreatitis events occurred in the control patients. There were 36 reports of pancreatic cancer in these studies. Of these cases, 2 used linagliptin, 2 used alogliptin, 1 used vildagliptin, 7 used saxagliptin while 6 used sitagliptin. The remaining 18 cases occurred among controls.

CONCLUSION: Although GLP-1 based agents are associated with pancreatic enzyme elevation, we were unable to confirm a significant risk of pancreatitis or pancreatic cancer.

Towards better meta-analyses in assisted reproductive technology: Fixed, random or multivariate models?

AIM: To study the validity of the fixed, random, and multivariate meta-analytical models applied in meta-analyses in artificial reproduction technique.

METHODS: Based on common characteristics of in vitro fertilization (IVF) meta-analyses, we simulated a large number of data to compare results issued from the fixed model (FM) with the random model (RM). For multiple endpoints meta-analysis (MA), we compared the univariate RM with the multivariate model (MM). Finally, we illustrate our findings in re-analyzing a recent MA.

RESULTS: In our review, although a homogeneous effect was excluded in 89% of the MAs (11%), FM was utilized in 41 studies (82%). From simulations, a concordance of 59% ± 6% was found between the two tests, with up to 65% of falsely significant results with FM. The Q-test on studies characterized by substantial heterogeneity falsely accepted homogeneity in 46% of studies. Comparing separate univariate RM and MM on multiple endpoints studies, MM reduces the between endpoint discrepancy (BED) of 68%, and increases the power of 57% ± 8%. In the example dealing with the controversial effect of luteneizing hormone supplementation to follicle stimulating hormone during ovarian stimulation in IVF cycles, MM reduced BED by 66%, and consistent effects were found for all the endpoints, irrespective of partial reporting.

CONCLUSION: The FM generally may produce falsely significant differences. The RM should always be used. For multiple endpoints, the MM constitutes the best option.

Antireflux surgery vs medical treatment for gastroesophageal reflux disease: A meta-analysis

AIM: To compare the effect of antireflux surgery with medicine in treating gastroesophageal reflux disease (GERD) patients using meta- analysis.

METHODS: MEDLINE, Embase and the Cochrane Library were searched. We only included randomized controlled trials (RCTs) comparing the effect of surgical intervention with medical therapy for GERD. Statistical analyses were performed using RevMan 5.2 and STATA 12.0 software. RevMan 5.2 was used to assess the risk of bias and calculate the pooled effect size, while Stata 12.0 was used to evaluate publication bias and for sensitivity analysis. We evaluated the primary outcomes with GERD-/health-related quality of life in short (one to three years) and long (three to twelve years) periods of follow-up. Secondary outcomes evaluated were DeMeester scores and the percentage of time that pH < 4 to evaluate the degree of acid exposure.

RESULTS: This meta-analysis included 7 studies with 1972 patients. It showed a positive effect of antireflux surgery compared with medical treatment in terms of health-related quality of life [standardized mean difference (SMD) = 0.18; 95%CI: 0.01 to 0.34] and GERD-related quality of life (SMD = 0.35; 95%CI: 0.11 to 0.59). We also conducted the subgroup analyses based on follow-up periods and found that surgery remained more effective than medicine over the short to medium follow-up time, but the advantage of antireflux surgery probably not maintained for long time. GERD-related quality of life in the surgical group was significantly higher than medical group for the < 3 years follow-up (SMD = 0.45; 95%CI: 0.23 to 0.66); the difference was not statistically significant when the follow-up time was ≥ 3 years (SMD = 0.30; 95%CI: -0.10 to 0.69). Meta-analysis showed a statistically significant difference between the surgical group and medical group in the percentage of time that pH < 4 (SMD = 0.38; 95%CI: 0.14 to 0.61). Meta-analysis indicated a positive effect of antireflux surgery compared with medical treatment concerning DeMeester scores (SMD = 0.32; 95%CI: 0.00 to 0.65).

CONCLUSION: Although both were effective, in some respects surgical intervention was more effective than medical therapy to treat GERD when follow-up time was up to three years.

Radiofrequency ablation with or without transarterial chemoembolization for hepatocellular carcinoma: A systematic review and meta-analysis

AIM: To determine whether combined transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) improve overall and recurrence-free survival (RFS) compared with RFA alone.

METHODS: We reviewed randomized clinical trials (RCTs) comparing overall survival rate as well as recurrence-free rate for hepatocellular carcinoma (HCC) between TACE-RFA therapy and RFA alone published before April 2015 by conducting a systematic review and meta-analysis. Eligible studies were identified by searching PubMed and EMBASE up to April 2015. Additional studies were retrieved via China Medical Collections, Google Scholar or a hand review of the reference lists of the retrieved articles. The summarized relative risks (RRs) with their 95%CIs were estimated using random-effects model. I² statistic was calculated to measure the heterogeneity of RRs across studies and Cochran’s Q test was used to test the statistical significance accordingly. Publication bias was assessed primarily based on visual assessment using a funnel plot, and secondly by using Egger’s regression asymmetry test or Begg’s rank correlation test as appropriate. Meta-regression was implemented to examine potential effect modifiers.

RESULTS: Nine single-center RCTs conducted in China and Japan were included, with a total of 618 patients with HCC; 321 of whom (51.9%) received TACE/RFA therapy and 297 received RFA alone. The pooled RRs with corresponding CIs comparing combined TACE/RFA to RFA alone were 1.12 (1.004-1.26) and 1.20 (1.02-1.41) for 1-year and 3-year survival rates, respectively. Similar positive associations were found for 1-year (1.19; 1.05-1.35) and 3-year (1.44; 1.00-2.07) RFS. The beneficial effect was more evident in patients with medium-sized (3-5 cm) tumors and among the Chinese population.

CONCLUSION: Combined TACE/RFA has a beneficial effect on survival and recurrence rates compared with RFA alone, especially for medium-sized HCC and among Chinese patients.

Traditional Chinese manual acupuncture for management of obesity: A systematic review

AIM: To evaluate the effectiveness and safety of acupuncture for the treatment of obesity by reviewing currently available randomised controlled trials.

METHODS: This review followed the Cochrane Handbook for Systematic Reviews of Interventions. Fifteen English and three Chinese databases were searched from their respective inceptions until July 2014. Key words used in the search consisted of acupuncture, needles, obesity, overweight, randomised trial and their synonyms. The risk of bias of included studies was assessed. The differences in effect size between acupuncture and control (including sham, no treatment, western medicine and dietary therapy/exercise) groups were compared using Cochrane Collaboration’s RevMan 5.3 software.

RESULTS: Two thousand six hundred and twenty-one records were identified; after full-text articles assessed for eligibility, 9 of them met inclusion criteria. Majority of included studies had unclear or high risk of bias across all domains. All included studies had high or unclear risk of bias in randomisation, blinding and outcome data. Meta-analysis showed that acupuncture was more effective for reducing body weight and body mass index than no treatment group. Manual acupuncture was also superior to dietary therapy alone for decreasing body weight. With dietary therapy as co-intervention, combined acupuncture group achieved lower body mass index than combined sham acupuncture group or dietary therapy alone group at the end of treatment period. No severe adverse events from acupuncture group were reported from all included studies.

CONCLUSION: Due to the poor quality of included studies the effectiveness of acupuncture cannot be concluded. Better-designed, large-scale, randomised, sham-controlled clinical trials with long-term follow-up are needed.

How to impute study-specific standard deviations in meta-analyses of skewed continuous endpoints?

AIM: To compare four methods to approximate mean and standard deviation (SD) when only medians and interquartile ranges are provided.

METHODS: We performed simulated meta-analyses on six datasets of 15, 30, 50, 100, 500, and 1000 trials, respectively. Subjects were iteratively generated from one of the following seven scenarios: five theoretical continuous distributions [Normal, Normal (0, 1), Gamma, Exponential, and Bimodal] and two real-life distributions of intensive care unit stay and hospital stay. For each simulation, we calculated the pooled estimates assembling the study-specific medians and SD approximations: Conservative SD, less conservative SD, mean SD, or interquartile range. We provided a graphical evaluation of the standardized differences. To show which imputation method produced the best estimate, we ranked those differences and calculated the rate at which each estimate appeared as the best, second-best, third-best, or fourth-best.

RESULTS: Our results demonstrated that the best pooled estimate for the overall mean and SD was provided by the median and interquartile range (mean standardized estimates: 4.5 ± 2.2, P = 0.14) or by the median and the SD conservative estimate (mean standardized estimates: 4.5 ± 3.5, P = 0.13). The less conservative approximation of SD appeared to be the worst method, exhibiting a significant difference from the reference method at the 90% confidence level. The method that ranked first most frequently is the interquartile range method (23/42 = 55%), particularly when data were generated according to the Standard Normal, Gamma, and Exponential distributions. The second-best is the conservative SD method (15/42 = 36%), particularly for data from a bimodal distribution and for the intensive care unit stay variable.

CONCLUSION: Meta-analytic estimates are not significantly affected by approximating the missing values of mean and SD with the correspondent values for median and interquartile range.

Brassiere wearing and breast cancer risk: A systematic review and meta-analysis

AIM: To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast cancer.

METHODS: Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; original research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a first reviewer and verified by a second. Study quality was rated according to predefined criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was available.

RESULTS: Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times of increased odds.

CONCLUSION: The present review demonstrates insufficient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifically, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.

Application of meta-analysis to specific research fields: Lessons learned

Scientific research is challenged to translate findings from multiple, often conflicting, clinical trials into a simple answer of whether a treatment works or not. The public and healthcare providers alike frequently voice their frustrations when the media reports a treatment working on one day, but seemingly the next day reports a study refuting the previous one. Meta-analyses are being used more commonly by researchers to convey an understandable summary of scientific studies to the general public and healthcare providers. As time goes by, we have learned how to improve meta-analytic techniques to reflect more valid results and when it is appropriate to pool or not to pool results from different studies. Retrospective reviews often don’t acknowledge this learning curve and may fail to recommend the most current valid guidelines. This editorial presents an example of how the current use of meta-analysis has shifted in one field (the therapeutic effects of probiotics) and recommendations on how to correctly interpret the results of such an analysis.

Sleep-associated movement disorders and the risk of cardiovascular disease: A systematic review and meta-analysis

AIM: To investigate whether an association exists between sleep-associated movement disorders and cardiovascular disease (CVD).

METHODS: Several studies have observed the relationship of sleep-associated movement disorders such as restless legs syndrome (RLS) and periodic limb movements during sleep with CVD, but the results were still contradictory. We performed an extensive literature search on PubMed, Medline and Web of Science published from inception to December 2014. Additional studies were manually searched from bibliographies of retrieved studies. Meta-analyses were conducted with Stata version 12.0 (Stata Corp, College Station, Texas). Pooled odds ratios (ORs) and 95%CIs were calculated to assess the strength of association using the random effects model. Sensitivity and subgroup analyses were performed to explore the underlying sources of heterogeneity. The publication bias was detected using Egger’s test and Begg’s test.

RESULTS: A total of 781 unique citations were indentified from electronic databases and 13 articles in English were finally selected. Among these studies, nine are cohort studies; two are case-control studies; and two are cross-sectional studies. The results showed that the summary OR of CVD associated with sleep-associated movement was 1.51 (95%CI: 1.29-1.77) in a random-effects model. There was significant heterogeneity between individual studies (P for heterogeneity = 0.005, I² = 57.6%). Further analysis revealed that a large-scale cohort study may account for this heterogeneity. A significant association was also found between RLS and CVD (OR = 1.54, 95%CI: 1.24-1.92). In a fixed-effects model, we determined a significant relationship between sleep-associated movement disorders and coronary artery disease (CAD) (OR = 1.34, 95%CI: 1.16-1.54; P for heterogeneity = 0.210; I² = 30.0%). Our meta-analysis suggests that sleep-associated movement disorders are associated with prevalence of CVD and CAD.

CONCLUSION: This finding indicates that sleep-associated movement disorders may prove to be predictive of underlying CVD.

Effectiveness of 7-valent pneumococcal conjugate vaccine: A meta-analysis of post-marketing studies

AIM: To investigate the 7-valent pneumococcal conjugate vaccine (PCV7) effectiveness.

METHODS: A systematic literature review of studies which evaluated the effectiveness of PCV7 vaccine was performed searching the keyword “heptavalent pneumococcal conjugate vaccine” in PubMed and Scopus until March 16, 2013. The selection of potential eligible articles was done by two researchers independently on the basis of abstract and title and only post-marketing studies were included in the systematic review. Data extraction was carried out by two researchers with respect to invasive pneumococcal diseases due to both all and vaccine serotypes in pre-vaccine and post-vaccine periods in children less than 5 years. Results of studies which were considered suitable for meta-analysis were combined by means of relative risk (RR) with 95%CI. Vaccine effectiveness was calculated as (1-RR) × 100. Heterogeneity was assessed by I² and a random effects model was used to combine data in the case of heterogeneity. RevMan 5 was used to pool data.

RESULTS: On the whole, 757 eligible papers were identified from the literature search in PubMed and Scopus. Of them, 62 were finally considered in the systematic review and 38 were included in the meta-analysis. In all post-marketing studies included in the systematic review the incidence of invasive pneumococcal diseases due to vaccine serotypes declined significantly with the exception of few studies showing stability or a slight, but not significant, increase. Furthermore most of studies highlighted also a reduction in the incidence of invasive pneumococcal diseases due to all serotypes. With regards to meta-analysis, a random effects model was used to combine data because of the high heterogeneity. Data combination showed that the effectiveness of PCV7 in reducing invasive pneumococcal diseases due to vaccine serotypes and to all serotypes was 84% (95%CI: 74%-90%) and 53% (95%CI: 46%-59%) respectively. These results are confirmatory with respect to the efficacy of PCV7 against invasive pneumococcal diseases due to vaccine serotypes.

CONCLUSION: PCV7 implementation determines a significant decrease of invasive pneumococcal diseases.

Evolving role of salvage reirradiation: Is global harmonization required before treatment guidelines can be developed?

Up to 90% of patients initially treated with curative-intent radiotherapy (RT) will experience locoregional failure. Historically, reirradiation (ReRT) was offered purely with palliative intent, if considered at all, due to concerns surrounding toxicity, tolerance of normal tissues, and choice of appropriate dose schedule. With technological advancements in RT delivery, coupled with longer survival in many malignancies secondary to improvements in systemic therapy, a small subset of patients presenting with localized recurrence is increasingly being offered salvage ReRT. However, this is largely on an ad hoc basis, guided mainly by small retrospective, single-institution reports. The patient population retreated, RT modality, dose received, degree of attrition and follow-up are extremely variable. The opportunity presently exists to apply lessons learned from the harmonization of the research efforts within the bone metastases community to the salvage ReRT situation: the adoption of common endpoints, minimum features to be incorporated into clinical trial design, and methods of data analysis and reporting. The ReRT data available must be harmonized so that valid, clinically applicable conclusions can be drawn. Collaboration in the form of an international registry of prospectively collected outcomes of patients reirradiated for cure for a variety of tumour sites would further support the evolution of Radiation Oncology towards personalized medicine, and away from the current “one-dose-fits-all” approach.

Is the traditional Chinese medicine helpful for patients with hematologic malignant diseases? A meta-analysis of randomized controlled trials

AIM: To evaluate the efficacy of traditional Chinese medicine (TCM) for the treatment of hematologic malignant diseases.

METHODS: We searched the Cochrane CENTRAL, PubMed, Embase, Web of Science, AMED, CNKI, Wanfang Platform; China Sinomed and the clinical trial registry web sites and Googlescholar electronically up to June 19^th, 2014 and hand searched related publications. Only randomized controlled trials (RCTs) researching on whether TCM as the adjuvant treatment improved the effect for hematologic malignant diseases were included. Two reviewers extracted data and evaluated the studies independently. Pooled risk ratios (RR) were calculated as outcome measures. Our primary outcomes were the overall response (OR) rate.

RESULTS: We retrieved 13143 references and included 11 RCTs involved 891 participants after screening. Because the non-significant heterogeneity we used the fixed effect model to combine data and TCM had a significantly higher OR and CR (complete response) rates than the control [RR = 1.17, 95%CI: (1.10, 1.25), P < 0.00001; RR = 1.24, 95%CI: (1.11, 1.37), P < 0.0001, respectively]. Only three studies included in the survival rate analysis. We combined them with random effects model and there was no significant difference between the TCM and control arms. Because of the low heterogeneity we used the fixed effect model to combine the non-hematologic adverse effects (AEs) data. Our results showed that TCM significantly decreased non-hematologic AEs rates we researched, the gastrointestinal reaction [RR = 0.50, 95%CI: (0.37, 0.68), P < 0.0001], liver and/or kidney injury [RR = 0.37, 95%CI: (0.26, 0.53), P < 0.00001] and heart injury [RR = 0.24, 95%CI: (0.09, 0.68), P = 0.007]. Additionally, TCM had a trend to decrease the infection rate [RR = 0.16, (0.02, 1.12), P = 0.07], but not statistically significantly.

CONCLUSION: TCM increases OR and CR rates for hematologic malignances and reduces treatment associated serious non-hematologic AEs. Therefore, TCM should be included in the treatment of hematologic malignances.

Development of the Documentation and Appraisal Review Tool for systematic reviews

AIM: To develop a tool to more explicitly assess and document the quality of systematic reviews.

METHODS: We developed the Documentation and Appraisal Review Tool (DART) using epidemiologic principles of study design and the following resources: the modified Overview Quality Assessment Questionnaire (modified OQAQ), Assessment of Multiple Systematic Reviews (AMSTAR), the Cochrane Handbook, and the standards promoted by the Agency for Healthcare Research and Quality, and the Institutes of Medicine (IOM). We designed the DART tool to include the following: more detail to provide guidance and improve standardization of use, an approach to assess quality of systematic reviews addressing a variety of research designs, and additional space for recording notes to facilitate recall. DART underwent multiple rounds of testing with methodologists of varying levels of training and experience. Based on the results of six phases of pilot testing, we revised DART to improve performance, clarity and consistency. Pilot testing also included comparisons between DART, and the two most commonly used tools to evaluate the quality of systematic reviews, the modified OQAQ and AMSTAR.

RESULTS: Compared to AMSTAR and modified OQAQ, DART includes two unique questions and several questions covered by modified OQAQ or AMSTAR but not both. Modified OQAQ and DART had the highest reporting consistency. Four AMSTAR questions were unclear and elicited inconsistent responses. Identifying reviewer rationale was most difficult using the modified OQAQ tool, and easiest using DART. DART allows for documentation of reviewer rationale, facilitating reconciliation between reviewers and documentation for future updates. DART also provides a comprehensive, systematic approach for reviewers with limited experience with systematic review methodology, to critically analyze systematic reviews. In addition, DART is the only one of the three tools to explicitly include quality review for biases specific to observational studies. This is now more widely recognized as important for assessing risk in order to generate recommendations that balance benefit to harm. The tool also includes the assessment of standards recommended by the March 2011 IOM Standards for Systematic Review.

CONCLUSION: This comprehensive tool improves upon existing tools for assessing the quality of systematic reviews and guides reviewers through critically analyzing a systematic review.

Systematic reviews and meta-analyses: Why are they clinically significant?

This review aims to clarify the clinical significance of systematic reviews and meta-analyses by illustrating several classical examples. Firstly, systematic reviews can provide the highest level of evidence for clinical decisions. Secondly, systematic reviews can propose unresolved issues and future directions. Thirdly, systematic reviews can avoid harm to the human body. Fourthly, systematic reviews can prevent a waste of resources. Generally speaking, clinical researchers should be encouraged to perform systematic reviews and meta-analyses.

Red meat intake and the risk of endometrial cancer: Meta-analysis of observational studies

AIM: To evaluate whether red meat intake is related to the risk of endometrial cancer (EC) using meta-analysis.

METHODS: We searched PubMed, EMBASE, and the Cochrane Library up to June 2013, using common keywords related to red meat and EC. Case-control studies and cohort studies comparing the risk of endometrial cancer among categories by the amount of intake were included. Eleven case-control studies and five cohort studies met our criteria. We performed a conventional and a dose-response meta-analysis of case-control studies using the DerSimonian-Laird method for random-effects. For cohort studies we performed a conventional meta-analysis. Publication bias was evaluated using Egger’s test.

RESULTS: In the meta-analysis of 11 case-control studies including 5419 cases and 12654 controls, higher red meat consumption was associated with an increased risk of EC [summary relative risk (SRR) = 1.43, 95%CI: 1.15-1.79; I² = 73.3% comparing extreme intake categories). In a dose-response analysis, for red meat intake of 100 g/d, SRR was 1.84 (95%CI: 1.64-2.05). In contrast, in the meta-analysis of five prospective studies including a total of 2549 cases among 247746 participants, no significant association between red meat intake and EC risk (SRR = 0.97, 95%CI: 0.85-1.11; I² = 4.9% comparing extreme intake categories) was observed.

CONCLUSION: Our meta-analysis found a significant linear association between red meat intake and EC risk based on case-control studies but this was not confirmed in prospective studies.

Unsaturation index and type 2 diabetes: Unknown, unloved

A useful parameter for interpreting analyses of membrane fatty-acid composition is the unsaturation index (UI), a measure of unsaturation that is calculated as the mean number of cis double bonds per fatty-acid residue multiplied by 100. The UI is a fundamental parameter that contains information about many membrane biophysical properties and behavior. UI is a crucial index for type 2 diabetes (T2D) and other disorders, yet it is not properly considered in the scientific community. The goal of the present editorial is to familiarize the scientific T2D community with the UI. The idea of early systemic cell-membrane disease necessitates new thinking and suggests that UI should feature prominently on the research agenda.

Addition of hip exercises to treatment of patellofemoral pain syndrome: A meta-analysis

AIM: To determine if the addition of hip-strengthening exercises decreases pain and improves function in patients with patellofemoral pain syndrome.

METHODS: The authors completed a systematic review searching eight databases (i.e., PubMed, Cochrane, CINHAL, MEDLINE, SportsDiscus, EMBASE, APTA Hooked on Evidence, and PEDro). Two independent reviewers screened and excluded studies if they did not meet the following inclusion criteria: subjects had a primary diagnosis of patellofemoral pain syndrome (PFPS), intervention group included hip-strengthening exercises, control group included a traditional physical therapy intervention, study included outcome measures of pain and/or function, study used a randomized controlled trial design, PEDro score was ≥ 7, and study was published in a peer-reviewed journal. Primary outcome measures were subjective scales of pain and function. These measures were converted to standardized mean difference [effect size (ES)], and a random-effects model was used to calculate the overall ES.

RESULTS: Two hundred eighty-three studies were screened for inclusion in our meta-analysis. Nine studies were deemed suitable for data extraction and analysis. A total of 426 subjects were used in the nine studies. Overall, there was a significant positive effect of hip-strengthening exercises on measures of pain and function in subjects with PFPS (ES = 0.94, P = 0.00004). None of the individual studies had a negative ES, with study ES ranging from 0.35 to 2.59. Because of the high degree of between-study variance (I² = 76%; Q = 34.0, P < 0.001), subgroup meta-analyses and meta-regressions were performed. None of the potential moderator variables that were investigated (e.g., outcome type, hip region targeted, duration of treatment) could explain a significant amount of the between-study variance in ES (P≥ 0.23).

CONCLUSION: Overall, the addition of hip-strengthening exercises to traditional physical therapy produced greater improvements in measures of pain and function.

Arthroscopic capsular release and manipulation under anaesthesia for frozen shoulders: A hot topic

A frozen shoulder is a common cause of shoulder pain and stiffness. The etiology and pathology of frozen shoulders is not fully understood yet. Frozen shoulder is characterized by a decrease in intra-articular volume and capsular compliance. This can lead to significant limitations in daily life. The majority of the patients can be treated conservatively, with functional recovery to be expected in two to three years. However, if conservative treatment fails, manipulation under anaesthesia and arthroscopic capsular release can both be considered as appropriate treatments. Manipulation is a traditionally well-established technique but in recent years it seems that arthroscopic capsular release has gained popularity. Manipulation is a relative time efficient and technically low-demanding procedure in which the glenohumeral joint is forced into different directions under general anaesthesia to release the capsular contracture, thereby increasing the range of motion of the joint. In arthroscopic capsular release the glenohumeral capsule can be released in a more controlled manner under direct vision. There are no prospective comparative trials available to display superiority of one procedure over the other. In addition, the optimal timing of both these interventions still has to be determined. An overview of the literature concerning this topic and a description of both procedures with its own advantages and disadvantages is provided.

Low back pain-related meta-analysis: Caution is needed when interpreting published research results

The systematic reviews (SRs) including a meta-analysis are considered as the top level of evidence. Although the existence of more than a hundred of low back pain (LBP)-related SRs seems very appealing and might therefore suggest significant evidence on the topic, a deep analysis indicates that several of these SRs included only very few studies. Other SRs raise concerns because they included some randomized controlled trials which had a low methodological quality, or some studies which differed significantly regarding the studied populations and/or the experimental procedure. The sometimes controversial results of different SRs conducted on the same topic also highlight the significant influence of the inclusion/exclusion criteria used in the SRs to select the articles. To conclude, although meta-analysis is at the top of the evidence pyramid and have several strengths, the conclusions drawn from SRs should always be interpreted with caution because they can also have weaknesses. This is true, whether it be for LBP-related SRs including a meta-analysis, or any other. Therefore a critical analysis of any SR is always needed before integrating the results of the SR in its own clinical practice. Furthermore, clinical reasoning remains crucial, especially to consider the potential differences between one’s patient and the patients included in the meta-analysis.

Meta-analysis of single strain probiotics for the eradication of Helicobacter pylori and prevention of adverse events

AIM: To assess the efficacy and safety of single strain probiotics for the: (1) eradication of Helicobacter pylori (H. pylori); (2) prevention of adverse events; and (3) prevention of antibiotic-associated diarrhea associated with eradication therapy.

METHODS: We searched PubMed (1960-2014), EMBASE (1974-2014), Cochrane Database of Systematic Reviews (1990-2014), and ISI Web of Science (2000-2014). Additionally, we conducted a grey literature search including contact with National Institutes of Health Clinical Trials Registry, abstracts from annual infectious disease and gastroenterology meetings, experts in the field and correspondence with authors. Randomized controlled trials of H. pylori positive adults or children treated with eradication therapy and assessing the adjunctive therapy with a single strain of probiotics were included. The primary outcomes were the rates of eradication of H. pylori and frequency of patients with adverse events or antibiotic-associated diarrhea. Outcomes were pooled using fixed or random-effects models to calculate the relative risk and corresponding 95%CI and weighted on study size. To explore possible explanations for heterogeneity, a priori subgroup analyses were conducted on daily probiotic dose, study population, and quality of the study. The overall quality of the evidence for each probiotic strain was assessed using the GRADE criteria.

RESULTS: A total of 25 randomized controlled trials (28 treatment arms, with a total of 3769 participants) assessed one of six single probiotic strains as adjunctive treatments to standard eradication therapy. Only one probiotic strain significantly improved H. pylori eradication rates: Saccharomyces boulardii (S. boulardii) CNCM I-745 [pooled relative risks (pRR) = 1.11, 95%CI: 1.07-1.16]. Only one probiotic strain (S. boulardii CNCM I-745) significantly prevented any adverse events (pRR = 0.42, 95%CI: 0.28-0.62). Both S. boulardii CNCM I-745 and Lactobacillus rhamnosus GG significantly reduced antibiotic-associated diarrhea (pRR = 0.47, 95%CI: 0.37-0.60 and pRR = 0.29, 95%CI: 0.17-0.48, respectively) associated with H. pylori eradication therapy. Meta-regression of sub-groups did not detect significant differences by dose, adult vs pediatric, symptom status, or study quality, but did find significant differences by the strain of probiotic. Potential mild publication bias was found for antibiotic-associated diarrhea, but not for eradication or adverse event outcomes. Analysis of the study quality illuminated areas for improvement in future studies (use of placebos, study size calculations, attrition reasons and discussion of limitations and generalizability).

CONCLUSION: The pooled evidence suggests that the adjunctive use of a few probiotic strains may improve H. pylori eradication rates and prevent the development of adverse events and antibiotic-associated diarrhea in those treated with standard eradication therapies. The type of probiotic strain was the most important factor in predicting efficacy.

Fate of meta-analyses: The case of Helicobacter pylori

AIM: To overview the current diversity of meta-analysis and the implementation of their results in international guidelines.

METHODS: Relevant meta-analysis were identified from PubMed/Medline. The topics of meta-analyses were determined. Some topics (genetics, extragastric tumors) were analysed separately. Core journals publishing meta-analyses on Helicobacter pylori were ranked. The rate of citation of meta-analysis in major guidelines was calculated.

RESULTS: Between 1992 and 2014, some 356 meta-analyses were published on PubMed. These mainly appeared in core journals, but were also found in 128 other journals. Eradicating of the infection was the most addressed topic with 134 articles. Meta-analyses were rarely used in formulating statements and recommendations in the international guidelines. In other topics - genetics, extraintestinal manifestations - meta-analyses were rather overused.

CONCLUSION: The implementation of meta-analysis in current guidelines is rather rare, while other topics benefit from many studies. A more extensive use of meta-analyses in evidence-based medicine is recommended in the future, otherwise their continuous proliferation will lose reason and scientific significance.

Why meta-analyses are important for complementary and alternative medicine research

Complementary and alternative medicine (CAM) is defined as a group of interventions that are not generally considered part of conventional medicine. This definition already implies that CAM interventions are often not systematically studied; and the research evidence from single trials on CAM is often limited by small sample sizes, unclear methodology, and inadequate statistics. As a result, both, significant and insignificant results are often hard to interpret based on single trials. Summarizing the evidence from single CAM trials, qualitative systematic reviews still have to deal with the same problems as individual trials as they can only rely on the original reports. Thus, effects of CAM interventions are often underestimated or overestimated based on single trials or qualitative systematic reviews. While meta-analyses still are limited by the methodological shortcomings of the included studies, a well-conducted meta-analysis can deal with two common problems of CAM trials: inadequate statistics that rely on within-group comparisons and small underpowered sample sizes. Although large and high quality trials are urgently needed for most CAM interventions, funding often is limited. Until higher quality research is available, meta-analyses provide a useful tool to investigate the actual level of evidence of currently published CAM trials. This editorial presents examples of meta-analyses in the field of CAM and discusses how they contribute to the consolidation of evidence.

Operative vs nonoperative treatment of displaced intra-articular calcaneal fracture: A meta-analysis of randomized controlled trials

AIM: To investigate clinical efficacy of displaced intra-articular calcaneal fracture (DIACF) following operation and nonoperation.

METHODS: Literature search was performed of PubMed and Cochrane Library by two independent authors to identify randomized controlled trials (RCTs) comparing operative vs nonoperative treatment of DIACF from inception to December 31^st, 2013. RCT quality was evaluated by the modified Jadad scale. Dichotomous variables were pooled using risk ratios by review manager 5.3 software. Fixed-effects or random-effects models were adopted with P > 0.05 or P≤ 0.05 for heterogeneity tests, respectively.

RESULTS: Eight RCTs comprising 767 cases met inclusion criteria. Results revealed that more surgically treated patients could resume pre-injury job (P = 0.006). No statistical differences were found between the two groups in residual pain (P = 0.33), shoe fitting problems (P = 0.07), limited walking distance (P = 0.56) or secondary late arthrodesis (P = 0.38). However, operative treatment was associated with a higher complication rate (P = 0.003). Subgroup analyses of specific complications revealed that except for a higher risk of superficial wound problems (P < 0.0001) in operative group, the two groups had similar complication rate in deep wound infection (P = 0.34), compartment syndrome (P = 0.46), thromboembolism (P = 0.32), reflex sympathetic dystrophy (P = 0.51) or traumatic arthritis secondary to DIACF (P = 0.43).

CONCLUSION: Current evidence demonstrates that compared with operative treatment, conservative treatment of DIACF lead to similar clinical outcomes regarding residual pain, shoe fitting, walking distance and secondary subtalar arthrodesis but a significantly lower complication rate.

Effect of supervised exercise on aerobic capacity in cancer survivors: Adherence and workload predict variance in effect

AIM: To examine the efficacy of supervised aerobic exercise training on aerobic capacity in survivors of cancer.

METHODS: We conducted a systematic search identifying randomized controlled trials of supervised aerobic exercise interventions among adult cancer survivors with aerobic capacity (VO_2max/peak) as the primary outcome. We calculated pooled effect sizes and performed multiple regression moderator analysis.

RESULTS: We identified 18 studies including 1149 survivors of cancer. Studies included mixed cancer groups (4 studies), breast cancer (10 studies), hematological cancers (2 studies), lung cancer (1 study) and liver cancer (1 study). Survivors of cancer who participated in supervised aerobic exercise training improved aerobic capacity (VO_2peak) more than controls (18 comparisons, 1093 participants; standardized mean effect: 0.74; 95%CI: 0.52, 0.96; P < 0.001). However, there was significant heterogeneity among the included trials (I²: 63%; P < 0.001). Sixty-six percent of the between-study heterogeneity was explained by differences in exercise adherence and total exercise workload among studies (R²: 65.8%; P < 0.04).

CONCLUSION: Supervised aerobic exercise training provides a moderate-to-large beneficial effect on aerobic capacity among survivors of cancer. Aerobic capacity was improved to a greater degree in exercise studies with better participant attendance and higher overall exercise workload.

Association between SHBG (TAAAA)n and AR (CAG)n polymorphisms and PCOS risk: A meta-analysis

AIM: To systematically assess the association between sex hormone-binding globulin (SHBG) (TAAAA)n and androgen receptor (AR) (CAG)n polymorphisms and polycystic ovarian syndrome (PCOS) risk.

METHODS: We searched MEDLINE (PubMed), EMBASE and Web of Science database from inception to May 2014. To avoid missing any additional studies, we looked through all the references of relevant articles. Case-control studies concerning the (CAG)n variants in the AR gene or the (TAAAA)n polymorphism in the SHBG gene in PCOS patients were included. Five studies regarding the (TAAAA)n polymorphism in the SHBG gene and 14 studies regarding the (CAG)n polymorphism in the AR gene met our criteria. Odd ratio (OR) and weighted mean difference (WMD) were selected as the effect size measurements to evaluate the influence of the (TAAAA)n polymorphism and (CAG)n variants on PCOS risk. Begg’s test was used for the evaluation of publication bias.

RESULTS: With respect to the relationship between the (TAAAA)n polymorphism and PCOS risk, the statistical results showed that there was no significant difference between PCOS patients and controls in the alleles of TAAAA (S: OR = 0.91, 95%CI: 0.78-1.05; L: OR = 1.10, 95%CI: 0.95-1.27). Subgroup analyses of the combination of alleles indicated similar results (short-short: OR = 0.87, 95%CI: 0.66-1.14; short-long: OR = 1.12, 95%CI: 0.86-1.46; long-long: OR = 1.03, 95%CI: 0.72-1.47). As for the relationship between the (CAG)n polymorphism and PCOS risk, we found no association between CAG repeat variants and PCOS risk (WDM = 0.03, 95%CI: -0.13-0.08). Subgroup analyses by race and diagnosis criteria indicated the same results (Asian: WMD = -0.03, 95%CI: -0.14-0.07; Caucasian: WMD = -0.02, 95%CI: -0.24-0.21; the criteria of Rotterdam: WMD = 0.01, 95%CI: -0.01-0.03).

CONCLUSION: There is no association between (TAAAA)n polymorphism in SHBG gene, (CAG)n repeat variants in AR gene and PCOS.

Antithrombotic treatment in chronic heart failure and sinus rhythm: Systematic review

AIM: To assess the efficacy and safety of antithrombotic drugs (antiplatelet or anticoagulant drugs) compared to no antithrombotic treatment or placebo in patients with heart failure (HF) and sinus rhythm.

METHODS: We searched Medline and Cochrane Library for randomized controlled trials evaluating antithrombotic treatment and no antithrombotic treatment in patients with HF and sinus rhythm. Risk ratio (RR) and 95%CIs were estimated performing meta-analysis with random effects method.

RESULTS: Two studies met the inclusion criteria: Heart failure Long-term Antithrombotic Study and Warfarin/Aspirin Study in Heart failure, with 336 patients and mean follow-up 1.8-2.25 years. Stroke risk was not reduced by acetylsalicylic acid (RR = 1.18, 95%CI: 0.17-8.15), oral anticoagulation (RR = 0.30, 95%CI: 0.03-2.65) or overall antithrombotic drugs (RR = 0.52, 95%CI: 0.10-2.74). Acetylsalicylic acid showed a significant increased risk of worsening HF (RR = 1.78, 95%CI: 1.08-2.92), while oral anticoagulation had no impact in this outcome (RR = 1.03, 95%CI: 0.61-1.75). Overall antithrombotic drugs showed a significant risk increase of major bleeding (RR = 6.99, 95%CI: 0.89-54.64).

CONCLUSION: Best available evidence does not support the routine use of antithrombotic drugs in patients with HF and sinus rhythm. These drugs, particularly oral anticoagulation has the hazard of increase significantly major bleeding risk.

Hypertension in Zimbabwe: A meta-analysis to quantify its burden and policy implications

AIM: To estimate the pooled prevalence of hypertension in Zimbabwe and describe its trend since independence in 1980 using secondary source data.

METHODS: MEDLINE, EMBASE and Scopus databases from April 1980 to December 2013 were searched for population and community based studies on the prevalence of hypertension among adults (≥ 18 years) in Zimbabwe. The key words used were “prevalence”, “epidemiologic studies”, “hypertension” or “high blood pressure”, based on the cut-off (≥ 140 mmHg systolic blood pressure and/or ≥ 90 mmHg diastolic blood pressure). We conducted a meta-analysis on the published studies, using the random-effects model to estimate the pooled prevalence.

RESULTS: The search retrieved 87 publications, of which four studies met the selection criteria. The four studies had a total of 4829 study participants between 1997 and 2010 across 5 provinces in Zimbabwe. Two studies were in urban areas, while the other two had mixed study settings (urban and rural). The overall pooled prevalence of hypertension was 30% (95%CI: 19%, 42%, I²= 98%, χ² = 164.15, P = 0.00).

CONCLUSION: Our results show a high prevalence of hypertension in Zimbabwe, with urban areas having higher prevalence than rural areas.

Prophylactic tracheal intubation for upper GI bleeding: A meta-analysis

AIM: To evaluate usefulness of prophylactically intubating upper gastrointestinal bleeding (UGIB) patients.

METHODS: UGIB results in a significant number of hospital admissions annually with endoscopy being the key intervention. In these patients, risks are associated with the bleeding and the procedure, including pulmonary aspiration. However, very little literature is available assessing the use of prophylactic endotracheal intubation on aspiration in these patients. A comprehensive search was performed in May 2014 in Scopus, CINAHL, Cochrane databases, PubMed/Medline, Embase, and published abstracts from national gastroenterology meetings in the United States (2004-2014). Included studies examined UGIB patients and compared prophylactic intubation to no intubation before endoscopy. Meta-analysis was conducted using RevMan 5.2 by Mantel-Haenszel and DerSimonian and Laird models with results presented as odds ratio for aspiration, pneumonia (within 48 h), and mortality. Funnel plots were utilized for publication bias and I² measure of inconsistency for heterogeneity assessments.

RESULTS: Initial search identified 571 articles. Of these articles, 10 relevant peer-reviewed articles in English and two relevant abstracts were selected to review by two independent authors (Almashhrawi AA and Bechtold ML). Of these studies, eight were excluded: Five did not have a control arm, one was a letter the editor, one was a survey study, and one was focused on prevention of UGIB. Therefore, four studies (N = 367) were included. Of the UGIB patients prophylactically intubated before endoscopy, pneumonia (within 48 h) was identified in 20 of 134 (14.9%) patients as compared to 5 of 95 (5.3%) patients that were not intubated prophylactically (P = 0.02). Despite observed trends, no significant differences were found for mortality (P = 0.18) or aspiration (P = 0.11).

CONCLUSION: Pneumonia within 48 h is more likely in UGIB patients who received prophylactic endotracheal intubation prior to endoscopy.

Effect of institutional volume on laparoscopic cholecystectomy outcomes: Systematic review and meta-analysis

AIM: To determine whether institutional laparoscopy cholecystectomy (LC) volume affects rates of mortality, conversion to open surgery, bile leakage and bile duct injury (BDI).

METHODS: Eligible studies were prospective or retrospective cohort studies that provided data on outcomes from consecutive LC procedures in single institutions. Relevant outcomes were mortality, conversion to open surgery, bile leakage and BDI. We performed a Medline search and extracted data. A regression analysis using generalized estimating equations were used to determine the influence of annual institutional LC caseload on outcomes. A sensitivity analysis was performed including only those studies that were published after 1995.

RESULTS: Seventy-three cohorts (127404 LC procedures) were included. Average complication rates were 0.06% for mortality, 3.23% for conversion, 0.44% for bile leakage and 0.28% for bile duct injury. Annual institutional caseload did not influence rates of mortality (P = 0.142), bile leakage (P = 0.111) or bile duct injury (P = 0.198) although increasing caseload was associated with reduced incidence of conversion (P = 0.019). Results from the sensitivity analyses were similar.

CONCLUSION: Institutional volume is a determinant of LC complications. It is unclear whether volume is directly linked to complication rates or whether it is an index for protocolised care.

Risk of infectious diseases and cutaneous tumours in solid organ recipients: A meta-analysis of literature

AIM: To compare the risk of cutaneous infections and tumours in kidney transplant recipients with data recently published about this topic.

METHODS: In the present work, we evaluated the incidence of bacterial, fungal and viral cutaneous infectious diseases and the development of skin cancers in a cohort of 436 patients who underwent a renal transplantation. The median age at transplantation of our patients was 50 years and the median duration of the immunosuppression was of 7.2 years. Data obtained from our cohort were compared with those obtained by a systematic review of the literature of the last 20 years about the same topic.

RESULTS: Infectious diseases were the most frequent dermatological disorders that were diagnosed after transplantation, affecting about the 16.5% of patients. Herpes virus reactivation occurs in about the 35% of patients and is more common within 6 mo from transplantation, whereas when the immunosuppression is reduced, skin infections are mainly represented by Human Papilloma Virus infections and localized mycosis, such as pityriasis versicolor and superficial candidiasis. Bacterial infections were relatively rare and occur mainly in the first months after transplantation. The cumulative risk to develop skin cancer enhance significantly over the time, as consequence of long-term immunosuppressive regiments. Endogenous and exogenous risk factors, as well as the schedule of immunosuppression can play a role and justify the different incidence of skin cancer in the various series.

CONCLUSION: Skin infections and cancer, commonly diagnosed in transplanted patients, impact on survival and life-quality, justifying the realization of follow-up programs for the early diagnosis and treatment.

Systematic review and meta-analysis of Statins-Fibrates therapy in diabetic dyslipidemia patients

AIM: To evaluate the efficacy, effect of preventing cardiovascular diseases and safety of statins-fibrates combination therapy in diabetic dyslipidemia patients.

METHODS: We searched the databases of MEDLINE, EMBASE, web of knowledge and Cochrane central register of Controlled Trials for literatures about the coadministration of statins and fibrates as the treatment of patients with dyslipidemia and type 2 diabetes mellitus. We included related randomized controlled trials, controlled clinical trials and cross-sectional studies and excluded animal trials and clinical observations. The primary endpoints outcomes were the concentration of plasma total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). The secondary outcomes were cardiovascular diseases (CVD) and adverse events.

RESULTS: Ten studies were included in this meta-analysis. For lipid modifying efficacy, the combination of statins and fibrates therapy had more significant effect on reducing TC [P = 0.004, weighted mean difference (WMD) = -8.19, 95%CI: -13.82--2.56] and TG concentration (P < 0.001, WMD = -47.29, 95%CI: -68.66--25.92) and increasing HDL-C concentration (P < 0.00001, WMD = 3.79, 95%CI: 2.25-5.33) when compared with statins monotherapy, while the effect of reducing LDL-C concentration (P = 0.50, WMD = -2.52, 95%CI: -9.76-4.72) was insignificant. To fibrates monotherapy, the combination therapy was more effective on reducing TC (P < 0.00001, WMD = -48.51, 95%CI: -57.14--39.89), TG (P < 0.00001, WMD = -26.07, 95%CI: -30.96--21.18), LDL-C concentration (P < 0.00001, WMD = -45.74, 95%CI: -53.35--38.13) and increasing HDL-C concentration (P = 0.04, WMD = 1.38, 95%CI: 0.04-2.73). For cardiovascular diseases, the coadministration therapy had no significant effect on reducing the incidence of these events when compared with monotherapy (For primary clinical endpoints, P = 0.12, OR = 0.61, 95%CI: 0.33-1.14); for secondary clinical endpoints, P = 0.13, OR = 0.66, 95%CI: 0.38-1.14). For adverse events happened during the follow-up, both the incidence of hepatic-related (alanine aminotransferase and/or aspartate aminotransferase of patients were ≥ 3 times of upper limit of normal) (P = 0.38, OR = 0.55, 95%CI: 0.15-2.06) and muscular-related (myopathy and/or creatine phosphokinase ≥ 3 times of upper limit of normal) adverse events (P = 0.10, OR = 1.62, 95%CI: 0.91-2.86) had no significant difference between these two therapies.

CONCLUSION: The results showed statins-fibrates combination therapy was more effective on lipid modification and well tolerated but there was no significant effect on preventing cardiovascular diseases.

Alcohol consumption and the risk of Barrett’s esophagus: A meta-analysis

AIM: To evaluate the possible association between alcohol consumption and Barrett’s esophagus (BE).

METHODS: We performed a systematic literature search of multiple online electronic databases. Inclusion criteria entailed studies about alcohol and BE. Meta-analysis was conducted to evaluate odds ratio (OR) and 95%CIs for the association between alcohol consumption and BE.

RESULTS: Twenty studies comprising 4758 patients with BE were included in the meta-analysis. The risk of BE in patients with alcohol consumption was increased compared with control groups (OR = 1.01; 95%CI: 1.00-1.02), especially in case-control and cohort, European and Asian, and hospital studies, but there was a decreased risk of BE associated with alcohol consumption from American studies (OR = 0.86; 95%CI: 0.77-0.96). At the same time, there was no significant association between BE and alcohol consumption in community studies (OR = 0.97; 95%CI: 0.84-1.12) and the type of alcohol (wine, beer and liquor) studies.

CONCLUSION: Our meta-analysis found that alcohol consumption was associated with an increased risk of BE, especially for European and Asian drinkers.

Diagnostic yield of third eye retroscope on adenoma detection during colonoscopy: A systematic review and meta-analysis

AIM: To determine the diagnostic yield of the “third eye retroscope”, on adenoma detection rate during screening colonoscopy.

METHODS: The “third eye retroscope” when used with standard colonoscopy provides an additional retrograde view to visualize lesions on the proximal aspects of folds and flexures. We searched MEDLINE (PubMed and Ovid), SCOPUS (including MEDLINE and EMBASE databases), Cochrane Database of Systemic Reviews, Google Scholar, and CINAHL Plus databases to identify studies that evaluated diagnostic yield of “third eye retroscope” during screening colonoscopy. DerSimonian Laird random effects model was used to generate the overall effect for each outcome. We evaluated statistical heterogeneity among the studies by using the Cochran Q statistic and quantified by I² statistics.

RESULTS: Four distinct studies with a total of 920 patients, mean age 59.83 (95%CI: 56.77-62.83) years, were included in the review. The additional adenoma detection rate (AADR) defined as the number of additional adenomas identified due to “third eye retroscope” device in comparison to standard colonoscopy alone was 19.9% (95%CI: 7.3-43.9). AADR for right and left colon were 13.9% (95%CI: 9.4-20) and 10.7 (95%CI: 1.9-42), respectively. AADR for polyps ≥ 6 mm and ≥ 10 mm were 24.6% (95%CI: 16.6-34.9) and 24.2% (95%CI: 12.9-40.8), respectively. The additional polyp detection rate defined as the number of additional polyps identified due to “third eye retroscope” device in comparison to standard colonoscopy alone was 19.8% (95%CI: 7.9-41.8). There were no complications reported with use of “third eye retroscope” device.

CONCLUSION: The “third eye retroscope” device when used with standard colonoscopy is safe and detects 19.9% additional adenomas, compared to standard colonoscopy alone.

Hydrocephalus after subarachnoid hemorrhage: A meta-analytic comparison of aneurysm treatments

AIM: To compare two treatments for ruptured cerebral aneurysm with reference to the relative risk of developing hydrocephalus.

METHODS: We reviewed the English language literature on the risk of developing hydrocephalus after aneurysm treatment. Data were divided by type of study (randomized controlled trial, cohort trial, nonrandomized comparison, prospectively- and retrospectively-collected observational study). They were also divided by type of aneurysm treatment (microvascular - clipping, or endovascular - coiling). Additional predictive variables collected for each publication were average age, gender distribution, measures of hemorrhage volume and subarachnoid hemorrhage severity, aneurysm locations, time to treatment, duration of follow-up and date of publication. We employed meta-analysis to calculate pooled risk ratios of developing hydrocephalus in cases receiving aneurysm clipping vs those receiving coiling. Meta-regression was used to correct pooled results for covariates.

RESULTS: Because indications for the two treatments are different, there is little clinical equipoise for treating most cases. The single randomized, controlled trial dealt with a small subset of ruptured aneurysms. Neither this nor pooled values from other studies which compared the two treatments had the power to demonstrate significant differences between the two treatments. Nor was there an apparent difference when observational data were meta-analytically pooled. However, when meta-regression was used to correct for predictive variables known to differ between the two treatment groups, a highly-significant difference appeared. Coiling is used more commonly in older, sicker patients with aneurysms in certain locations. These cases are more likely to develop hydrocephalus. When corrected for these covariates, the risk of hydrocephalus was found to be significantly lower in coiled vs clipped cases (P = 0.014).

CONCLUSION: Pooled observational data were necessary to demonstrate that coiling ruptured cerebral aneurysms is associated with a lower risk of developing hydrocephalus than is clipping.

Russian clinical research policy does not guarantee results availability

AIM: To investigate results availability from clinical studies enrolling Russian subjects and Russian clinical research policy.

METHODS: We analyzed Russian legislation and ethical regulations about drug and devices approval, clinical research registration and the results availability. In August 2012, we searched International Clinical Trials Registry Platform and clinicaltrials.gov to find all registered studies that had an investigational site in the territory of the Russian Federation. To find publication status, we searched the PubMed and Scirus bibliographical databases with trial registration number to find journal publications of the registered studies.

RESULTS: We identified 2062 registered research protocols comprising 2017 international and 45 protocols sponsored by the Russian funding agencies. The number of the studies enrolling Russian subjects increased dramatically from three studies in 2002 to 252 studies in 2012. Most studies (92%) were funded exclusively by industry, were interventions (94.6%), examined drugs (87%) and enrolled exclusively adults (86%) of both genders (89%). Only 383 (19%) of multinational studies and two (4.4%) of exclusively Russian studies were published. Posting of patient outcomes was available for 16% of the trials that recruited trial participants in the Russian territory including one study funded exclusively by Russian sponsors. Investigators terminated 99 studies of 38111 participants and did not provide the results in clinicaltrials.gov or in published manuscripts. Federal laws require clinical study registration and conflict of interest disclosure. However, routine monitoring of compliance to clinical research policy is not available.

CONCLUSION: Russian legislation does not guarantee the availability of clinical research results. Russian legislation should mandate transparent evidence- based market approval of the drugs and devices.

Anti-obesity drugs currently used and new compounds in clinical development

Obesity is a chronic disease which requires treatment. As lifestyle interventions alone hardly ever result in long-term weight loss, pharmacotherapy is an important adjunct to lifestyle measures to improve the induction and maintenance of weight loss. Owing to the limited options currently available for the pharmacological treatment of obesity, it is imperative to develop new safe compounds. This study aims to review the current medications approved by European Medicines Agency and United States Food and Drug Administration (FDA) for the treatment of obesity, focusing essentially on their benefits and risks, as well as on the new drugs which are presently under clinical trials. Moreover, it lists the anti-obesity agents that have been recently withdrawn from the market. A revision of the scientific literature was carried out, through a search on Pubmed for papers published from January 2010 to January 2013. Orlistat (Xenical^®) is currently the only long-term pharmacotherapy for obesity available in the European market, as rimonabant and sibutramine were withdrawn in 2008 and 2010, respectively, due to serious psychiatric and cardiovascular adverse effects. Lorcaserin (Belviq^®) and the association of phentermine and topiramate (Qsymia^TM) were recently approved by FDA. Orlistat suppresses appetite inhibiting gastrointestinal lipase, being its adverse effects mostly gastrointestinal. Lorcaserin activates 5-HT_2C receptors, phentermine is a norepinephrine releasing drug, and topiramate is an anticonvulsivant drug with weight loss properties.

Observed communication between oncologists and patients: A causal model of communication competence

AIM: To investigate and test a causal model derived from previous meta-analytic data of health provider behaviors and patient satisfaction.

METHODS: A literature search was conducted for relevant manuscripts that met the following criteria: Reported an analysis of provider-patient interaction in the context of an oncology interview; the study had to measure at least two of the variables of interest to the model (provider activity, provider patient-centered communication, provider facilitative communication, patient activity, patient involvement, and patient satisfaction or reduced anxiety); and the information had to be reported in a manner that permitted the calculation of a zero-order correlation between at least two of the variables under consideration. Data were transformed into correlation coefficients and compiled to produce the correlation matrix used for data analysis. The test of the causal model is a comparison of the expected correlation matrix generated using an Ordinary Least Squares method of estimation. The expected matrix is compared to the actual matrix of zero order correlation coefficients. A model is considered a possible fit if the level of deviation is less than expected due to random sampling error as measured by a chi-square statistic. The significance of the path coefficients was tested using a z test. Lastly, the Sobel test provides a test of the level of mediation provided by a variable and provides an estimate of the level of mediation for each connection. Such a test is warranted in models with multiple paths.

RESULTS: A test of the original model indicated a lack of fit with the summary data. The largest discrepancy in the model was between the patient satisfaction and the provider patient-centered utterances. The observed correlation was far larger than expected given a mediated relationship. The test of a modified model was undertaken to determine possible fit. The corrected model provides a fit to within tolerance as evaluated by the test statistic, χ² (8, average n = 342) = 10.22. Each of the path coefficients for the model reveals that each one can be considered significant, P < 0.05. The Sobel test examining the impact of the mediating variables demonstrated that patient involvement is a significant mediator in the model, Sobel statistic = 3.56, P < 0.05. Patient active was also demonstrated to be a significant mediator in the model, Sobel statistic = 4.21, P < 0.05. The statistics indicate that patient behavior mediates the relationship between provider behavior and patient satisfaction with the interaction.

CONCLUSION: The results demonstrate empirical support for the importance of patient-centered care and satisfy the need for empirical casual support of provider-patient behaviors on health outcomes.

Using fluorodeoxy-D-glucose-positron emission tomography to monitor neoadjuvant chemotherapy response in sarcoma: A meta-analysis

AIM: To systematically evaluate the accuracy of 18-fluorodeoxy-D-glucose-positron emission tomography (18-FDG PET) to assess response to neoadjuvant chemotherapy in bone and soft tissue sarcomas.

METHODS: Studies published in English language regarding the accuracy of F-18 FDG PET for the indication were retrieved from MEDLINE. The QUADAS tool was utilized for methodological quality appraisal. Relevant data were extracted, and quantitative data synthesis included pooled estimation and subgroup analysis.

RESULTS: A total of fifteen studies involving 420 patients with pathologically confirmed sarcoma were collected. Methodological quality was relatively high. The pooled sensitivity and specificity of PET to predict histopathological response were 87% (95%CI: 81%-91%) and 83% (95%CI: 77%-87%), respectively. Ten studies employed a lower standardized uptake value (SUV) after chemotherapies (mostly 2.5) and/or a higher SUV reduction rate (mostly around 50%) as PET criteria of good response. Subgroup analysis showed that PET exhibited a significantly better specificity in osteosarcoma (OS) and Ewing sarcoma (ES) than in soft-tissue sarcoma (STS) (91% vs 75%, P < 0.05), and a higher specificity in pediatric patients than in adults (90% vs 74%, P < 0.01). PET yielded a lower specificity in ifosfamide-contained chemotherapies than in the alternative regimen (70% vs 97%, P < 0.01).

CONCLUSION: F-18 FDG PET is promising to predict neoadjuvant therapy response in sarcoma, especially in pediatric patients with OS or ES. Certain chemotherapeutic agents could potentially cause false positives of PET.

Female-specific vs conventional knee prostheses after total knee arthroplasty: A meta-analysis

AIM: To study whether female-specific prostheses are superior to conventional prostheses after total knee arthroplasty (TKA) by conducting this meta-analysis to evaluate the effects of the 2 different designs.

METHODS: A systematic electronic search was conducted in the databases of PubMed, EMBASE and the Cochrane Library for prospective and retrospective trials. Meta-analysis was performed for the outcomes, including range of motion (ROM), Knee Society score, Hospital for Special Surgery scores (HSS) and complications including deep infection, manipulation under anesthesia (MUA), revisions, anterior knee pain, deep vein thrombosis and overhang rate. Meta-analysis was conducted where applicable. Weighted mean difference (WMD) and odds ratio were calculated according to study type.

RESULTS: Seven studies including 1174 knees were eligible for data extraction and pooled analysis. The overhang rate of female-specific prostheses was significantly lower than the conventional ones (WMD, 3.25; 95%CI: 0.00-0.27; P = 0.001). ROM in the female-specific prostheses group after TKA tended to be greater than the conventional prostheses group; however, with insignificant difference (WMD, 2.48; 95%CI: -0.83-5.78; P = 0.14). HSS (WMD, 0.48; 95%CI: -1.45-0.88; P = 0.63) and complications including deep infection (WMD, 0.39; 95%CI: 0.19-3.08; P =0 .70), MUA (WMD, 1.53; 95%CI: 0.02-1.61; P = 0.13) and revisions (WMD, 0.55; 95%CI: 0.07-4.34; P = 0.13) were all comparable between the two groups with at least 1 year follow-up. Other indexes were revealed to be similar between the two treatments with a descriptive analytical method.

CONCLUSION: Although the overhang rate is lower with female-specific prostheses, the current evidence does not support that female-specific prostheses outweigh conventional ones after TKA.

Meta-analysis of bivariate P values

AIM: To propose a new meta-analysis method for bivariate P value which account for the paired structure.

METHODS: Studies that look to test two different features from the same sample gives rise to bivariate P value. A relevant example of this is testing for periodicity as well expression from time-course gene expression studies. Kocak et al (2010) uses George and Mudholkar’ (1983) “Difference of Two Logit-Sums” method to pool bivariate P value across independent experiments, assuming independence within a pair. As bivariate P value need not to be independent within a given study, we propose a new meta-analysis approach for pooling bivariate P value across independent experiments, which accounts for potential correlation between paired P-values. We compare the “Difference of Two Logit Sums”method with our novel approach in terms of their sensitivity and specificity through extensive simulations by generating P value samples from most commonly used tests namely, Z test, t test, chi-square test, and F test, with varying sample sizes and correlation structure.

RESULTS: The simulations results showed that our new meta-analysis approach for correlated and uncorrelated bivariate P value has much more desirable sensitivity and specificity features compared to the existing method, which treats each member of the paired P value as independent. We also compare these meta-analysis approaches on bivariate P value from periodicity and expression tests of 4936 S.Pombe genes from 10 independent time-course experiments and we showed that our new approach ranks the periodic, conserved, and cycling genes significantly higher, and detects many more periodic, “conserved” and “cycling” genes among the top 100 genes, compared to the ‘Difference of Two Logit-Sums’ method. Finally, we used our meta-analytic approach to compare the relative evidence in the association of pre-term birth with preschool wheezing versus pre-school asthma.

CONCLUSION: The new meta-analysis method has much better sensitivity and specific characteristics compared to the “Difference of Two-Logit Sums” method and it is not computationally more expensive.

Decision-tree analysis for cost-effective management of solitary pulmonary nodules in China

AIM: To analyze the cost-effectiveness of the diagnosis of solitary pulmonary nodule (SPN) in China.

METHODS: Decision analysis models were constructed to assess the cost-effectiveness of four strategies for the management of SPN: computed tomography (CT) alone, CT plus CT-guided automated cutting needle biopsy (ACNB), CT plus positron emission tomography/computed tomography (PET/CT), CT plus diffusion-weighted magnetic resonance imaging (DWI) plus PET/CT.

RESULTS: The prevalence of lung cancer among SPN discovered in the clinical setting was approximately 50%. The CT plus ACNB strategy had higher diagnostic accuracies (87% vs 81%), with a cost saving of ￥1945 RMB per patient, and reducing unnecessary thoracotomy by 16.5%; this was associated with a 4.5% missed diagnosis rate. CT plus DWI plus PET/CT strategy also had higher accuracies (95% vs 81%), with a cost saving of ￥590 RMB per patient, and reducing unnecessary thoracotomy by 13.5%; this was accompanied by 0.3% missed diagnosis rate. CT plus PET strategy is cost effective at a prevalence rate of 0-34%, but there was a larger prevalence range of lung cancer for CT plus ACNB strategy (from 0 to 0.6) and CT plus DWI plus PET/CT strategy(from 0 to 0.64).

CONCLUSION: CT plus DWI plus PET/CT strategy was cost-effective, and had a higher accuracy accompanied by a lower missed diagnosis rate than CT plus ACNB strategy.

Robot-assisted vs laparoscopy-assisted gastrectomy for gastric cancer: A meta-analysis based on 3518 subjects

AIM: To compare the short-term clinical outcomes of robot-assisted gastrectomy (RAG) with laparoscopy-assisted gastrectomy (LAG) in gastric cancer patients.

METHODS: Articles were identified through a literature search of Pubmed, EMBASE, Scopus, Web of Science, Chinese National Knowledge Infrastructure and the Cochrane Library. Weighted mean differences (WMDs) and odds ratios (ORs) were selected as effect sizes for quantitative variables and qualitative variables, respectively. And 95%CIs were also calculated.

RESULTS: A total of 13 studies with 3518 patients were included. RAG was associated with longer operative time (WMD = 46.26 min, 95%CI: 31.89-60.63, P < 0.00001), less blood loss [WMD = -37.19 mL, 95%CI: -60.16-(-14.23), P = 0.002] and shorter postoperative hospital stay [WMD = -0.65 d, 95%CI: -1.24-(-0.05), P = 0.03] than LAG. No significant difference in the numbers of retrieved lymph nodes was found between the two groups (WMD = 1.46, 95%CI: -0.19-3.10, P = 0.08). There was no significant difference in mortality (OR = 1.55, 95%CI: 0.49-4.94, P = 0.45), overall complications (OR = 1.00, 95%CI: 0.80-1.26, P = 0.98), anastomosis leakage (OR = 1.02, 95%CI: 0.62-1.65, P = 0.95) and anastomosis stenosis rates (OR = 0.54, 95%CI: 0.18-1.57, P = 0.25).

CONCLUSION: RAG is effective and safe in the treatment of gastric cancer. RAG is a promising alternative to laparoscopic surgery. Long-term randomized controlled studies with large scale and improved designs are needed to further evaluate the long-term outcomes.