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BMJ Open Jan 2021To determine the effects of coenzyme Q10 (CoQ10) for reduction in the severity, frequency of migraine attacks and duration of headache in adult patients with migraine. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To determine the effects of coenzyme Q10 (CoQ10) for reduction in the severity, frequency of migraine attacks and duration of headache in adult patients with migraine.
DESIGN
Systematic review and meta-analysis.
DATA SOURCES
Cochrane Central Register of Controlled Trials, CENTRAL, MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Psychological Information Database (PsycINFO) from inception till December 2019.
STUDY SELECTION
All randomised control trials comparing CoQ10 with placebo or used as an adjunct treatment included in this meta-analysis. Cross-over designs and controlled clinical trials were excluded.
DATA SYNTHESIS
Heterogeneity at face value by comparing populations, settings, interventions and outcomes were measured and statistical heterogeneity was assessed by means of the I statistic. The treatment effect for dichotomous outcomes were using risk ratios and risk difference, and for continuous outcomes, mean differences (MDs) or standardised mean difference; both with 95% CIs were used. Subgroup analyses were carried out for dosage of CoQ10 and if CoQ10 combined with another supplementation. Sensitivity analysis was used to investigate the impact risk of bias for sequence generation and allocation concealment of included studies.
RESULTS
Six studies with a total of 371 participants were included in the meta-analysis. There is no statistically significant reduction in severity of migraine headache with CoQ10 supplementation. CoQ10 supplementation reduced the duration of headache attacks compared with the control group (MD: -0.19; 95% CI: -0.27 to -0.11; random effects; I statistic=0%; p<0.00001). CoQ10 usage reduced the frequency of migraine headache compared with the control group (MD: -1.52; 95% CI: -2.40 to -0.65; random effects; I statistic=0%; p<0.001).
CONCLUSION
CoQ10 appears to have beneficial effects in reducing duration and frequency of migraine attack.
PROSPERO REGISTRATION NUMBER
CRD42019126127.
Topics: Adult; Dietary Supplements; Humans; Migraine Disorders; Ubiquinone
PubMed: 33402403
DOI: 10.1136/bmjopen-2020-039358 -
Journal of the American Heart... Jun 2023Background Although previous observational studies have shown an association between anemia and cardiovascular disease (CVD), the underlying causal relationship between... (Meta-Analysis)
Meta-Analysis
Background Although previous observational studies have shown an association between anemia and cardiovascular disease (CVD), the underlying causal relationship between anemia and CVD remains uncertain. Methods and Results We conducted a 2-sample bidirectional Mendelian randomization (MR) study to assess the causal association between anemia and CVD. We extracted summary statistics data for anemia, heart failure (HF), coronary artery disease (CAD), atrial fibrillation, any stroke, and any ischemic stroke (AIS) from relevant published genome-wide association studies. After rigorous quality control steps, independent single-nucleotide polymorphisms for each disease were selected as instrumental variables. Inverse-variance weighting was used as the primary method to estimate the causal association between anemia and CVD in the 2-sample MR analysis. Simultaneously, we performed a series of multiple methods analyses (median weighting, maximum likelihood [MR robust adjusted profile score]), sensitivity analyses (Cochran's test and MR-Egger intercept, leave-one-out test [MR pleiotropy residual sum and outlier]), instrumental variable strength evaluations ( statistic), and statistic power estimates to verify the robustness and reliability of our results. Furthermore, the associations between anemia and CVD from different studies, including the UK Biobank and FinnGen studies, were combined by meta-analysis. The MR analysis showed that genetically predicted anemia was significantly associated with HF risk at the Bonferroni-corrected significance level (odds ratio [OR], 1.11 [95% CI, 1.04-1.18]; =0.002) and was suggestively associated with CAD risk (OR, 1.11 [95% CI, 1.02-1.22]; =0.020). However, the associations between anemia and atrial fibrillation, any stroke, or AIS were not statistically significant. In the reverse MR analysis, we found that genetic susceptibility to HF, CAD, and AIS was significantly associated with anemia risk. The ORs of HF, CAD, and AIS were 1.64 (95% CI, 1.39-1.94; =7.60E-09), 1.16 (95% CI, 1.08-1.24; =2.32E-05), and 1.30 (95% CI, 1.11-1.52; =0.001), respectively. Genetically predicted atrial fibrillation was suggestively associated with anemia (OR, 1.06 [95% CI, 1.01-1.12]; =0.015). Sensitivity analyses found weak evidence of horizontal pleiotropy and heterogeneity, which ensured the robustness and reliability of the results. Meta-analysis also showed the statistically significant association between anemia and HF risk. Conclusions Our study supports bidirectional causality between anemia and HF and significant associations between genetic predisposition to CAD and AIS with anemia, which contributes to the clinical management of both diseases.
Topics: Humans; Cardiovascular Diseases; Atrial Fibrillation; Genome-Wide Association Study; Mendelian Randomization Analysis; Reproducibility of Results; Heart Failure; Coronary Artery Disease; Anemia; Genetic Predisposition to Disease; Stroke
PubMed: 37301769
DOI: 10.1161/JAHA.123.029689 -
Reproductive Health Apr 2021This article challenges the "tyranny of P-value" and promote more valuable and applicable interpretations of the results of research on health care delivery. We provide...
This article challenges the "tyranny of P-value" and promote more valuable and applicable interpretations of the results of research on health care delivery. We provide here solid arguments to retire statistical significance as the unique way to interpret results, after presenting the current state of the debate inside the scientific community. Instead, we promote reporting the much more informative confidence intervals and eventually adding exact P-values. We also provide some clues to integrate statistical and clinical significance by referring to minimal important differences and integrating the effect size of an intervention and the certainty of evidence ideally using the GRADE approach. We have argued against interpreting or reporting results as statistically significant or statistically non-significant. We recommend showing important clinical benefits with their confidence intervals in cases of point estimates compatible with results benefits and even important harms. It seems fair to report the point estimate and the more likely values along with a very clear statement of the implications of extremes of the intervals. We recommend drawing conclusions, considering the multiple factors besides P-values such as certainty of the evidence for each outcome, net benefit, economic considerations and values and preferences. We use several examples and figures to illustrate different scenarios and further suggest a wording to standardize the reporting. Several statistical measures have a role in the scientific communication of studies, but it is time to understand that there is life beyond the statistical significance. There is a great opportunity for improvement towards a more complete interpretation and to a more standardized reporting.
Topics: Data Interpretation, Statistical; Decision Making; Humans; Jurisprudence; Statistics as Topic
PubMed: 33865412
DOI: 10.1186/s12978-021-01131-w -
Cureus Sep 2022Introduction Decompressive hemicraniectomy (DHC) is a last-resort treatment for refractory intracranial hypertension. Perioperative morbidity is associated with high...
Introduction Decompressive hemicraniectomy (DHC) is a last-resort treatment for refractory intracranial hypertension. Perioperative morbidity is associated with high risks of wound healing disturbances (WHD). Recently, a retromastoidal frontoparietooccipital (RMF) incision type was performed to avoid healing disturbance due to enhanced tissue flap perfusion compared to the classical reverse "question mark" ("Dandy flap") incision. The goal of this study was to analyze the details of tissue healing problems in DHC. Materials and methods A total of 60 patients who underwent DHC were retrospectively analyzed. In 30 patients the "Dandy flap" incision (group A) and in 30 patients the RMF incision (group B) was made. Since no evidence-based data for the incision type that favors better wound healing exists, the form of incision was left at the surgeon´s discretion. Documentation of the patients was screened for the incidence of WHD: wound necrosis, dehiscence, and cerebrospinal fluid (CSF) leakage. Patient age, the time interval from surgery until the appearance of WHD, the length of surgeries in minutes, and the indications of the DHC were analyzed. A Chi-square test of independence was performed to examine the relationship between the incision type and the appearance of WHD with the statistical significance level set at p<0.05. The mean age of the patients, the mean time interval from surgery until the occurrence of WHD, and the mean length of the surgery between the two groups were compared using an independent sample t-test with the statistical significance level set at p<0.05. Results The most common indication for DHC in both groups was malignant MCA infarction (n=20, 66.6% for group A and n=16, 53.3% for group B). CSF leakage was 20% of the most frequent WHD in each group. Wound necrosis was observed only in group A. Although group B showed 13.3% fewer WHD than group A, this difference was not statistically significant. There was no statistically significant difference in the time range between surgery and the occurrence of WHD between the two groups. The length of surgery in group B was significantly shorter than in group A (120.2 mins vs. 103.7 mins). Conclusion A noticeable trend for reduced WHD was observed in the patient group using the RMF incision type although the difference was not statistically significant. We praise that the RMF incision allows an optimized skin-flap vascularization and, thereby, facilitates better wound healing. We were able to show a statistically shorter length of surgery with the RMF incision in contrast to the classic "Dandy flap" incision. Larger multicenter studies should be implemented to analyze and address the major advantages and pitfalls of the routinely applied incision techniques.
PubMed: 36133503
DOI: 10.7759/cureus.29260 -
Journal of Science and Medicine in Sport Mar 2023We aimed to examine the bias for statistical significance using published confidence intervals in sport and exercise medicine research. (Observational Study)
Observational Study
OBJECTIVES
We aimed to examine the bias for statistical significance using published confidence intervals in sport and exercise medicine research.
DESIGN
Observational study.
METHODS
The abstracts of 48,390 articles, published in 18 sports and exercise medicine journals between 2002 and 2022, were searched using a validated text-mining algorithm that identified and extracted ratio confidence intervals (odds, hazard, and risk ratios). The algorithm identified 1744 abstracts that included ratio confidence intervals, from which 4484 intervals were extracted. After excluding ineligible intervals, the analysis used 3819 intervals, reported as 95 % confidence intervals, from 1599 articles. The cumulative distributions of lower and upper confidence limits were plotted to identify any abnormal patterns, particularly around a ratio of 1 (the null hypothesis). The distributions were compared to those from unbiased reference data, which was not subjected to p-hacking or publication bias. A bias for statistical significance was further investigated using a histogram plot of z-values calculated from the extracted 95 % confidence intervals.
RESULTS
There was a marked change in the cumulative distribution of lower and upper bound intervals just over and just under a ratio of 1. The bias for statistical significance was also clear in a stark under-representation of z-values between -1.96 and +1.96, corresponding to p-values above 0.05.
CONCLUSIONS
There was an excess of published research with statistically significant results just below the standard significance threshold of 0.05, which is indicative of publication bias. Transparent research practices, including the use of registered reports, are needed to reduce the bias in published research.
Topics: Humans; Bias; Publication Bias; Sports; Exercise; Odds Ratio
PubMed: 36966124
DOI: 10.1016/j.jsams.2023.03.002 -
Problems and alternatives of testing significance using null hypothesis and -value in food research.Food Science and Biotechnology May 2023A testing method to identify statistically significant differences by comparing the significance level and the probability value based on the Null Hypothesis... (Review)
Review
A testing method to identify statistically significant differences by comparing the significance level and the probability value based on the Null Hypothesis Significance Test (NHST) has been used in food research. However, problems with this testing method have been discussed. Several alternatives to the NHST and the -value test methods have been proposed including lowering the -value threshold and using confidence interval (CI), effect size, and Bayesian statistics. The CI estimates the extent of the effect or difference and determines the presence or absence of statistical significance. The effect size index determines the degree of effect difference and allows for the comparison of various statistical results. Bayesian statistics enable predictions to be made even when only a small amount of data is available. In conclusion, CI, effect size, and Bayesian statistics can complement or replace traditional statistical tests in food research by replacing the use of NHST and -value.
PubMed: 37363053
DOI: 10.1007/s10068-023-01348-4 -
Human Reproduction (Oxford, England) Nov 2023What were the frequency and temporal trends of reporting P-values and effect measures in the abstracts of reproductive medicine studies in 1990-2022, how were reported...
STUDY QUESTION
What were the frequency and temporal trends of reporting P-values and effect measures in the abstracts of reproductive medicine studies in 1990-2022, how were reported P-values distributed, and what proportion of articles that present with statistical inference reported statistically significant results, i.e. 'positive' results?
SUMMARY ANSWER
Around one in six abstracts reported P-values alone without effect measures, while the prevalence of effect measures, whether reported alone or accompanied by P-values, has been increasing, especially in meta-analyses and randomized controlled trials (RCTs); the reported P-values were frequently observed around certain cut-off values, notably at 0.001, 0.01, or 0.05, and among abstracts present with statistical inference (i.e. P-value, CIs, or significant terms), a large majority (77%) reported at least one statistically significant finding.
WHAT IS KNOWN ALREADY
Publishing or reporting only results that show a 'positive' finding causes bias in evaluating interventions and risk factors and may incur adverse health outcomes for patients.
UNLABELLED
Despite efforts to minimize publication reporting bias in medical research, it remains unclear whether the magnitude and patterns of the bias have changed over time.
STUDY DESIGN, SIZE, DURATION
We studied abstracts of reproductive medicine studies from 1990 to 2022. The reproductive medicine studies were published in 23 first-quartile journals under the category of Obstetrics and Gynaecology and Reproductive Biology in Journal Citation Reports and 5 high-impact general medical journals (The Journal of the American Medical Association, The Lancet, The BMJ, The New England Journal of Medicine, and PLoS Medicine). Articles without abstracts, animal studies, and non-research articles, such as case reports or guidelines, were excluded.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Automated text-mining was used to extract three types of statistical significance reporting, including P-values, CIs, and text description. Meanwhile, abstracts were text-mined for the presence of effect size metrics and Bayes factors. Five hundred abstracts were randomly selected and manually checked for the accuracy of automatic text extraction. The extracted statistical significance information was then analysed for temporal trends and distribution in general as well as in subgroups of study designs and journals.
MAIN RESULTS AND THE ROLE OF CHANCE
A total of 24 907 eligible reproductive medicine articles were identified from 170 739 screened articles published in 28 journals. The proportion of abstracts not reporting any statistical significance inference halved from 81% (95% CI, 76-84%) in 1990 to 40% (95% CI, 38-44%) in 2021, while reporting P-values alone remained relatively stable, at 15% (95% CI, 12-18%) in 1990 and 19% (95% CI, 16-22%) in 2021. By contrast, the proportion of abstracts reporting effect measures alone increased considerably from 4.1% (95% CI, 2.6-6.3%) in 1990 to 26% (95% CI, 23-29%) in 2021. Similarly, the proportion of abstracts reporting effect measures together with P-values showed substantial growth from 0.8% (95% CI, 0.3-2.2%) to 14% (95% CI, 12-17%) during the same timeframe. Of 30 182 statistical significance inferences, 56% (n = 17 077) conveyed statistical inferences via P-values alone, 30% (n = 8945) via text description alone such as significant or non-significant, 9.3% (n = 2820) via CIs alone, and 4.7% (n = 1340) via both CI and P-values. The reported P-values (n = 18 417), including both a continuum of P-values and dichotomized P-values, were frequently observed around common cut-off values such as 0.001 (20%), 0.05 (16%), and 0.01 (10%). Of the 13 200 reproductive medicine abstracts containing at least one statistical inference, 77% of abstracts made at least one statistically significant statement. Among articles that reported statistical inference, a decline in the proportion of making at least one statistically significant inference was only seen in RCTs, dropping from 71% (95% CI, 48-88%) in 1990 to 59% (95% CI, 42-73%) in 2021, whereas the proportion in the rest of study types remained almost constant over the years. Of abstracts that reported P-value, 87% (95% CI, 86-88%) reported at least one statistically significant P-value; it was 92% (95% CI, 82-97%) in 1990 and reached its peak at 97% (95% CI, 93-99%) in 2001 before declining to 81% (95% CI, 76-85%) in 2021.
LIMITATIONS, REASONS FOR CAUTION
First, our analysis focused solely on reporting patterns in abstracts but not full-text papers; however, in principle, abstracts should include condensed impartial information and avoid selective reporting. Second, while we attempted to identify all types of statistical significance reporting, our text mining was not flawless. However, the manual assessment showed that inaccuracies were not frequent.
WIDER IMPLICATIONS OF THE FINDINGS
There is a welcome trend that effect measures are increasingly reported in the abstracts of reproductive medicine studies, specifically in RCTs and meta-analyses. Publication reporting bias remains a major concern. Inflated estimates of interventions and risk factors could harm decisions built upon biased evidence, including clinical recommendations and planning of future research.
STUDY FUNDING/COMPETING INTEREST(S)
No funding was received for this study. B.W.M. is supported by an NHMRC Investigator grant (GNT1176437); B.W.M. reports research grants and travel support from Merck and consultancy from Merch and ObsEva. W.L. is supported by an NHMRC Investigator Grant (GNT2016729). Q.F. reports receiving a PhD scholarship from Merck. The other author has no conflict of interest to declare.
TRIAL REGISTRATION NUMBER
N/A.
PubMed: 38015794
DOI: 10.1093/humrep/dead248 -
Jornal de Pediatria 2021The study aimed to evaluate the link between the IL-4-C590T polymorphism and asthma susceptibility in children by meta-analysis. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The study aimed to evaluate the link between the IL-4-C590T polymorphism and asthma susceptibility in children by meta-analysis.
SOURCES
The study collected all the case-control studies found in PubMed, Embase, CNKI, Wanfang, VIP, and other databases until September 2019. Stata v. 15.0 was used to conduct meta-analysis, calculate the combined OR and its 95% CI, and then conduct subgroup analysis.
SUMMARY OF THE FINDINGS
Seven studies were included in the study, containing 860 cases and 810 controls. Relative to the C allele, the T allele at the IL-4-C590T locus was associated with susceptibility to asthma in children (OR = 1.45, 95% CI: 1.05-2.01). The results of ethnicity subgroup analysis showed that there was statistical significance, with OR = 1.61 (95% CI: 1.01-2.57) in the Asian population. In the dominant and recessive genetic models, the overall test and the Asian population subgroup analysis were statistically significant. In the homozygous model, there was statistical significance, but no statistical significance in heterozygous model.
CONCLUSIONS
The IL-4-C590T polymorphism was associated with asthma susceptibility, and T allele and TT genotype may increase the risk of asthma susceptibility in children, especially in the Asian population.
Topics: Asian People; Asthma; Child; Genetic Predisposition to Disease; Humans; Interleukin-4; Polymorphism, Single Nucleotide; Risk Factors
PubMed: 32781035
DOI: 10.1016/j.jped.2020.05.005 -
Cancers Mar 2022The diagnosis and prognostic outcome of STS pose a therapeutic challenge in an interdisciplinary setting. The treatment protocols are still discussed controversially.... (Review)
Review
The diagnosis and prognostic outcome of STS pose a therapeutic challenge in an interdisciplinary setting. The treatment protocols are still discussed controversially. This systematic meta-analysis aimed to determine prognostic factors leading to the development and recurrence of STS. Eligible studies that investigated potential risk factors such as smoking, genetic dispositions, toxins, chronic inflammation as well as prognostic relapse factors including radiation, chemotherapy and margins of resection were identified. Data from 24 studies published between 1993 and 2019 that comprised 6452 patients were pooled. A statistically significant effect developing STS was found in overall studies stating a causality between risk factors and the development of STS (p < 0.01). Although subgroup analysis did not meet statistical significances, it revealed a greater magnitude with smoking (p = 0.23), genetic predisposition (p = 0.13) chronic inflammation, (p = 0.20), and toxins (p = 0.14). Secondly, pooled analyses demonstrated a higher risk of relapse for margin of resection (p = 0.78), chemotherapy (p = 0.20) and radiation (p = 0.16); after 3 years of follow-up. Therefore, we were able to identify risk and relapse prognostic factors for STS, helping to diagnose and treat this low incidental cancer properly.
PubMed: 35267581
DOI: 10.3390/cancers14051273