ResearchPad - publication-ethics https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Meta-analysis of the correlation between dietary copper supply and broiler performance]]> https://www.researchpad.co/article/elastic_article_15740 To conduct a meta-analysis assessing the correlation between dietary copper supply and broiler performanceMethodsStudies that were published prior to January 2019 and reported the dietary copper supply and broiler growth performance were identified using search functions in the Web of Science, Springer, Elsevier, Science Direct, and Taylor & Francis Online databases; the Journal of Dairy Research; and China National Knowledge Infrastructure (CNKI). We performed stratified analyses on the possible sources of bias, including differences in the study locations and years of publication. The publication bias was assessed with Egger’s test method.ResultsA total of 12 randomized controlled trial (RCT) studies were eligible for inclusion. The pooled WMDs of the ADG, ADFI and FCR were -0.166 (95% CI: -1.587 to 1.254), -0.844 (95% CI: -1.536 to -0.152) and -0.029 (95% CI: -0.057 to 0.000), respectively. In the Israeli and Indian studies, the ADG and ADFI data in the experimental group were higher than those in the control group; however, in America, a relatively high FCR value was found in the experimental group compared to that in the control group. The analysis of the study period showed that for the 1980s and 2010s, the ADG and ADFI of the experimental group were lower than those of the control group, while, in the 1990s and 2010s, the FCR of the experimental group were lower than those of the control group. The observed values were adjusted for study effects, and a model was used to obtain the copper supplementation under the optimal production performance. The results showed that the adjusted average daily gain (ADG), average daily feed intake (ADFI), and feed to gain ratio (FCR) presented a quadratic relationship with Cu supplementation (P<0.05). The maximum value of ADG (31.84 g/d) is reached when Cu is added at amount of 158 mg/kg, and the minimum value of FCR (1.53) is reached when Cu is added at amount of 217 mg/kg. No significant publication bias existed in the studies (Egger's test: P value were 0.81, 0.71 and 0.14).ConclusionFrom this study, it can be concluded that the traditional copper addition is no longer suitable for modern broiler breeding; the higher copper content may be beneficial for the production performance of broilers. ]]> <![CDATA[The prevalence of hepatitis C virus in hemodialysis patients in Pakistan: A systematic review and meta-analysis]]> https://www.researchpad.co/article/elastic_article_14616 Hepatitis C virus (HCV) infection is one of the most common bloodborne viral infections reported in Pakistan. Frequent dialysis treatment of hemodialysis patients exposes them to a high risk of HCV infection. The main purpose of this paper is to quantify the prevalence of HCV in hemodialysis patients through a systematic review and meta-analysis.MethodsWe systematically searched PubMed, Medline, EMBASE, Pakistani Journals Online and Web of Science to identify studies published between 1 January 1995 and 30 October 2019, reporting on the prevalence of HCV infection in hemodialysis patients. Meta-analysis was performed using a random-effects model to obtain pooled estimates. A funnel plot was used in conjunction with Egger’s regression test for asymmetry and to assess publication bias. Meta-regression and subgroup analyses were used to identify potential sources of heterogeneity among the included studies. This review was registered on PROSPERO (registration number CRD42019159345).ResultsOut of 248 potential studies, 19 studies involving 3446 hemodialysis patients were included in the meta-analysis. The pooled prevalence of HCV in hemodialysis patients in Pakistan was 32.33% (95% CI: 25.73–39.30; I2 = 94.3%, p < 0.01). The subgroup analysis showed that the prevalence of HCV among hemodialysis patients in Punjab was significantly higher (37.52%; 95% CI: 26.66–49.03; I2 = 94.5, p < 0.01) than 34.42% (95% CI: 14.95–57.05; I2 = 91.3%, p < 0.01) in Baluchistan, 27.11% (95% CI: 15.81–40.12; I2 = 94.5, p < 0.01) in Sindh and 22.61% (95% CI: 17.45–28.2; I2 = 78.6, p < 0.0117) in Khyber Pukhtoonkhuwa.ConclusionsIn this study, we found a high prevalence (32.33%) of HCV infection in hemodialysis patients in Pakistan. Clinically, hemodialysis patients require more attention and resources than the general population. Preventive interventions are urgently needed to decrease the high risk of HCV infection in hemodialysis patients in Pakistan. ]]> <![CDATA[Association between cigarette smoking and the risk of dysmenorrhea: A meta-analysis of observational studies]]> https://www.researchpad.co/article/N299c77b6-7bcf-4190-8f14-766ff39e61a2

Background

Emerging studies have found inconsistent results on the potential relationship between cigarette smoking and dysmenorrhea. Therefore, the aim of this study was to quantitatively synthesize the previous findings on the preceding relationship using meta-analysis.

Methods

Previous studies on the association between cigarette smoking and dysmenorrhea, published not later than November 2019, were systematically searched, using MeSH heading and/or relevant terms, in the electronic databases of PubMed, Medline, Web of Science and EMBASE. The I2 statistic was used to assess heterogeneity, whose source was explored using subgroup analysis. A pooled effect size was obtained using random effects model, and sensitivity analysis was performed to assess the consistency of the pooled effect size.

Results

After a rigorous screening process, 24 studies involving 27,091 participants were included in this meta-analysis. The results indicated that smokers were 1.45 times more likely to develop dysmenorrhea than non-smokers (odds ratio (OR) = 1.45, 95% confidence interval (CI): 1.30–1.61). In addition, individuals classified as currently smoking were 1.50 times more likely to develop dysmenorrhea than those who were classified as never smoking (OR = 1.50, 95% CI: 1.33–1.70), whereas being a former smoker was 1.31 times more likely to develop dysmenorrhea than being a never smoker (OR = 1.31, 95% CI: 1.18–1.46). Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect.

Conclusion

The evidence from this meta-analysis indicated a significant association between cigarette smoking (both current and former smoking) and dysmenorrhea. The adverse effects of smoking provide further support for prevention of dysmenorrhea and emphasize the need to target women.

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<![CDATA[Scrutinizing assortative mating in birds]]> https://www.researchpad.co/article/5c784fead5eed0c4840078f1

It is often claimed that pair bonds preferentially form between individuals that resemble one another. Such assortative mating appears to be widespread throughout the animal kingdom. Yet it is unclear whether the apparent ubiquity of assortative mating arises primarily from mate choice (“like attracts like”), which can be constrained by same-sex competition for mates; from spatial or temporal separation; or from observer, reporting, publication, or search bias. Here, based on a conventional literature search, we find compelling meta-analytical evidence for size-assortative mating in birds (r = 0.178, 95% CI 0.142–0.215, 83 species, 35,591 pairs). However, our analyses reveal that this effect vanishes gradually with increased control of confounding factors. Specifically, the effect size decreased by 42% when we used previously unpublished data from nine long-term field studies, i.e., data free of reporting and publication bias (r = 0.103, 95% CI 0.074–0.132, eight species, 16,611 pairs). Moreover, in those data, assortative mating effectively disappeared when both partners were measured by independent observers or separately in space and time (mean r = 0.018, 95% CI −0.016–0.057). Likewise, we also found no evidence for assortative mating in a direct experimental test for mutual mate choice in captive populations of Zebra finches (r = −0.020, 95% CI −0.148–0.107, 1,414 pairs). These results highlight the importance of unpublished data in generating unbiased meta-analytical conclusions and suggest that the apparent ubiquity of assortative mating reported in the literature is overestimated and may not be driven by mate choice or mating competition for preferred mates.

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<![CDATA[Thoracic spine manipulation for the management of mechanical neck pain: A systematic review and meta-analysis]]> https://www.researchpad.co/article/5c6dc9ced5eed0c48452a202

Objective

To investigate the role of thoracic spine manipulation (TSM) on pain and disability in the management of mechanical neck pain (MNP).

Data sources

Electronic databases PubMed, CINAHL, Pedro, Embase, AMED, the Cochrane Library, and clinicaltrials.gov were searched in January 2018.

Study selection

Eligible studies were completed RCTs, written in English, had at least 2 groups with one group receiving TSM, had at least one measure of pain or disability, and included patients with MNP of any duration. The search identified 1717 potential articles, with 14 studies meeting inclusion criteria.

Study appraisal and synthesis methods

Methodological quality was evaluated independently by two authors using the guidelines published by the Cochrane Collaboration. Pooled analyses were analyzed using a random-effects model with inverse variance methods to calculate mean differences (MD) and 95% confidence intervals for pain (VAS 0-100mm, NPRS 0-10pts; 0 = no pain) and disability (NDI and NPQ 0–100%; 0 = no disability).

Results

Across the included studies, there was increased risk of bias for inadequate provider and participant blinding. The GRADE approach demonstrated an overall level of evidence ranging from very low to moderate. Meta-analysis that compared TSM to thoracic or cervical mobilization revealed a significant effect favoring the TSM group for pain (MD -13.63; 95% CI: -21.79, -5.46) and disability (MD -9.93; 95% CI: -14.38, -5.48). Meta-analysis that compared TSM to standard care revealed a significant effect favoring the TSM group for pain (MD -13.21; 95% CI: -21.87, -4.55) and disability (MD -11.36; 95% CI: -18.93, -3.78) at short-term follow-up, and a significant effect for disability (MD -4.75; 95% CI: -6.54, -2.95) at long-term follow-up. Meta-analysis that compared TSM to cervical spine manipulation revealed a non-significant effect (MD 3.43; 95% CI: -7.26, 14.11) for pain without a distinction between immediate and short-term follow-up.

Limitations

The greatest limitation in this systematic review was the heterogeneity among the studies making it difficult to assess the true clinical benefit, as well as the overall level of quality of evidence.

Conclusions

TSM has been shown to be more beneficial than thoracic mobilization, cervical mobilization, and standard care in the short-term, but no better than cervical manipulation or placebo thoracic spine manipulation to improve pain and disability.

Trial registration

PROSPERO CRD42017068287

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<![CDATA[Effects of angiotensin converting enzyme gene polymorphism on hypertension in Africa: A meta-analysis and systematic review]]> https://www.researchpad.co/article/5c6f1488d5eed0c48467a24c

Background

Hypertension is dramatically increasing in Africa with evidence of increased severity and resistance to treatment. Although angiotensin converting enzyme gene polymorphism is associated with higher prevalence of hypertension, the evidence is inconclusive on its influence on the emerging pattern in Africa. This meta-analysis is conducted to pool the available evidence to inform future research and interventions.

Methods

Articles published through May 2018 were systematically searched in PubMed, Scopus and EMBASE databases. Studies were assessed for inclusion by two independent researchers. Six models were used to assess the effect of angiotensin converting enzyme deletion-insertion gene polymorphism. Heterogeneity and publication bias were tested and sensitivity analysis was carried out. Odds ratio and 95% confidence intervals were measured for pooled effect. Both random effect and fixed effect models were used, whilst the frequency of DD, II and DI genotypes were computed and compared.

Result

Patients with D allele were 1.49 times more likely to develop essential hypertension compared with patients who carry the I allele (OR:1.49; CI:1.07, 2.07). Similarly, patients who had homozygous co-dominance genotype DD (i.e., DD vs II) were at a 2.17 times higher risk of essential hypertension compared to the co-dominant genotype II (OR:2.17, CI:1.79, 3.18), dominant model (I.e., DD+ID vs II) (OR:1.48; CI:1.03, 2.12), and recessive model (OR:1.64; CI:1.03, 2.61). On subgroup analysis, participants from Sub-Saharan Africa were more genetically susceptible to hypertension compared to their North Africa counterparts. There was no publication bias found, but there was high to moderate heterogeneity.

Conclusion

ACE I/D polymorphism is associated with essential hypertension in Africa in the allele contrast model, as well as the dominant, recessive and homozygous codominance model. On subgroup analysis, ACE I/D was associated with essential hypertension in patients from Sub-Saharan Africa but not in North Africa. A future large scale study, which includes different ethnic groups, is recommended.

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<![CDATA[Evidence that nonsignificant results are sometimes preferred: Reverse P-hacking or selective reporting?]]> https://www.researchpad.co/article/5c57e687d5eed0c484ef35c2

There is increased concern about poor scientific practices arising from an excessive focus on P-values. Two particularly worrisome practices are selective reporting of significant results and ‘P-hacking’. The latter is the manipulation of data collection, usage, or analyses to obtain statistically significant outcomes. Here, we introduce the novel, to our knowledge, concepts of selective reporting of nonsignificant results and ‘reverse P-hacking’ whereby researchers ensure that tests produce a nonsignificant result. We test whether these practices occur in experiments in which researchers randomly assign subjects to treatment and control groups to minimise differences in confounding variables that might affect the focal outcome. By chance alone, 5% of tests for a group difference in confounding variables should yield a significant result (P < 0.05). If researchers less often report significant findings and/or reverse P-hack to avoid significant outcomes that undermine the ethos that experimental and control groups only differ with respect to actively manipulated variables, we expect significant results from tests for group differences to be under-represented in the literature. We surveyed the behavioural ecology literature and found significantly more nonsignificant P-values reported for tests of group differences in potentially confounding variables than the expected 95% (P = 0.005; N = 250 studies). This novel, to our knowledge, publication bias could result from selective reporting of nonsignificant results and/or from reverse P-hacking. We encourage others to test for a bias toward publishing nonsignificant results in the equivalent context in their own research discipline.

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<![CDATA[Prognostic role of early D-dimer level in patients with acute ischemic stroke]]> https://www.researchpad.co/article/5c5df327d5eed0c484580dc4

Object

The purpose of our study was to assess the prognostic role of early D-dimer level in patients with acute ischemic stroke (AIS).

Methods

The included patients’ D-dimer levels have to be tested within 24 hours from stroke onset. Poor functional outcome was defined as modified Rankin Scale (mRS) ≥3. The endpoints included recurrence on 5-day diffusion-weighted imaging, 30-day mRS ≥3, 30-day mortality and 90-day mRS ≥3. Regarding to each endpoint, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the prognostic role of D-dimer in patients with AIS.

Results

A total of 2,479 patients were included. The results showed that elevated D-dimer levels were associated with recurrence on 5-day diffusion-weighted imaging (OR = 2.28, 95% CI = 1.32–3.95), 30-day mRS≥3 (OR = 1.59, 95% CI = 1.37–1.85), 30-day mortality (OR = 1.92, 95% CI = 1.27–2.90) and 90-day mRS≥3 (OR = 1.61, 95% CI = 1.05–2.46).

Conclusions

In conclusion, for patients with AIS, higher D-dimer level within 24 hours from stroke onset was associated with recurrence on 5-day diffusion-weighted imaging, mortality at 30 days, and poor functional outcome at both 30 days and 90 days. However, more studies are warranted to clarify this issue.

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<![CDATA[Percutaneous nephrolithotomy versus open surgery for surgical treatment of patients with staghorn stones: A systematic review and meta-analysis]]> https://www.researchpad.co/article/5c5ca31ad5eed0c48441f16c

Objectives

To compare the efficacy and safety of percutaneous nephrolithotomy (PCNL) and open surgery (OS) for surgical treatment of patients with staghorn stones based on published literatures.

Materials and methods

A comprehensive literature search of Pubmed, Embase, CNKI and Cochrane Library was conducted to identify studies comparing outcomes of PCNL and OS for treating patients with staghorn stones up to Jan 2018.

Results

There was no significant difference in final-SFR between PCNL and OS (odds ratio[OR]: 1.17; 95% confidence interval [CI]: 0.64, 2.15; p = 0.61), while PCNL provided a significantly lower immediate-SFR compared with OS (OR: 0.29; 95% CI: 0.16, 0.51; P < 0.0001). PCNL provided significantly lower overall complication rate, shorter operative times, hospitalization times, less blood loss and blood transfusion compared with OS (OR: 0.59; 95% CI: 0.41, 0.84; P = 0.004), (weighted mean difference [WMD]: -59.01mins; 95% CI: -81.09, -36.93; p < 0.00001), (WMD: -5.77days; 95% CI: -7.80, -3.74; p < 0.00001), (WMD: -138.29ml; 95% CI: -244.98, -31.6; p = 0.01) and (OR: 0.44; 95% CI: 0.29, 0.68; P = 0.00002), respectively. No significant differences were found in minor complications (Clavien I-II) (OR: 0.72; 95% CI: 0.47, 1.09; p = 0.12) and major complications (Clavien III-V) (OR: 0.5; 95% CI: 0.23, 1.08; P = 0.08). In subgroup analysis, there were no significant differences for overall complications and operative times between mini-PCNL and OS. In sensitivity analysis, there was no significant difference for overall complications between PCNL and OS.

Conclusion

Our analysis suggested that standard PCNL turns out to be a safe and feasible alternative for patients with staghorn stones compared to OS or mini-PCNL. Because of the inherent limitations of the included studies, further large sample, prospective, multi-centric and randomized control trials should be undertaken to confirm our findings.

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<![CDATA[Cigarette smoking as a risk factor for diabetic nephropathy: A systematic review and meta-analysis of prospective cohort studies]]> https://www.researchpad.co/article/5c61e925d5eed0c48496f872

Background

Observational studies suggested that tobacco smoking was associated with diabetic nephropathy (DN). However, the results were conflicting and inconsistent. In the study, we performed a meta-analysis to assess the relationship between tobacco smoking and the development of DN.

Materials and methods

We searched in PubMed, Embase, Web of Science and the Cochrane Library (CENTRAL) from database inception until Mar 8, 2018, and updated our search on May 1, 2018. We screened the reference lists of the retrieved articles. Only original prospective cohort studies which have investigated the association between smoking and DN incidence or its progression were included. Pooled HRs and 95% confidence intervals (CIs) were calculated using a random effects model.

Results

A total of 9 prospective cohort studies were identified, including more than 203337 participants. Compared with those of no smoking, smoking participants increased the risk of developing DN (HR = 1.07, 95% CI: 1.01–1.13, P = 0.01). The subgroup analysis showed that the current and total smoking may increase the risk of DN, but these results did not reach statistical significance (current: HR = 1.69, 95% CI = 0.79–3.64, p = 0.17; total: HR = 1.17, 95% CI = 0.97–1.41, p = 0.10), whereas former smoking significantly increased the risk of DN (HR = 1.04, 95% CI = 1.03–1.05, p<0.001). Compared with no-smokers, smokers showed an elevated risk of developing DN (HR = 1.05; 95% CI, 1.00–1.11, P = 0.05). In patients with T2DM, those who smoked were at an increased risk of developing DN, as compared to those who had never smoked (HR = 1.05; 95% CI, 1.00–1.11, P = 0.05). However, compared to no smoking, smoking did not increase the risk of DN development in patients with T2DM (HR = 1.15; 95% CI, 0.9–1.47, P = 0.25). Univariate and multivariate meta-regression did not find any confounding factors. No publication bias was found in the meta-analysis.

Conclusions

The present study highlighted that smoking was an independent risk factor for DN, especially in patients with T1DM. This is the first meta-analysis of prospective cohort studies to discuss the relationship between smoking and DN.

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<![CDATA[The effect of gender on food insecurity among HIV-infected people receiving anti-retroviral therapy: A systematic review and meta-analysis]]> https://www.researchpad.co/article/5c3d0159d5eed0c48403a7c8

Background

HIV-infected adults receiving anti-retroviral therapy have a high prevalence of food insecurity in both high- and low-income settings., Women bear an inequitable burden of food insecurity due to lack of control over resources and over household food allocation decision-making. The few studies conducted on the association between food insecurity and gender among HIV-infected adults have inconclusive findings. Therefore, the objective of this systematic review and meta-analysis was to estimate the pooled effect of gender on food insecurity among HIV-infected adults receiving antiretroviral therapy.

Method

We conducted an electronic, web-based search using PubMed, CINAHL, PopLine, MedNar, Embase, Cochrane library, the JBI Library, the Web of Science and Google Scholar. We included studies which reported the association between food insecurity and gender among HIV-infected adults receiving antiretroviral therapy whose age was greater than 18 years. The analysis was conducted using STATA 14 software. A random effects model was used to estimate the pooled effect a 95% confidence interval(CI). Forest plots were used to visualize the presence of heterogeneity. Funnel plots and Egger’s and Begg’s tests were used to check for publication bias.

Results

A total of 776 studies were identified of which seventeen studies were included in the meta-analysis, with a total of 5827 HIV infected adults receiving antiretroviral therapy. We found that the gender of HIV-infected adults receiving anti-retroviral therapy had statistically significant effects on food insecurity. The pooled odds of developing food insecurity among female HIV infected adults receiving anti-retroviral therapy was 53% higher than male HIV infected adults (OR: 1.53, 95% CI: 1.29, 1.83). Our analysis indicate the findings of studies conducted in the high-income countries showed weakest associations between gender and food insecurity than those conducted in low- and middle-income countries.

Conclusion

Our systematic review and meta-analysis showed statistically significant effect of gender on food insecurity among HIV-infected adults receiving anti-retroviral therapy in which odds of food insecurity was higher among female HIV infected adults compared to male HIV-infected adults. These findings suggest that the need to include within food and nutrition interventions for HIV-infected adults receiving antiretroviral treatment, culture- and context-specific gender-based policies to address the sex/gender related vulnerability to food insecurity.

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<![CDATA[Association of PPARGC1A Gly428Ser (rs8192678) polymorphism with potential for athletic ability and sports performance: A meta-analysis]]> https://www.researchpad.co/article/5c3fa576d5eed0c484ca4a0f

Background

Genetics plays a role in determining potential for athletic ability (AA) and sports performance (SP). In this study, AA involves comparing sedentary controls with competitive athletes in power and endurance activities as well as a mix between the two (SP). However, variable results from genetic association studies warrant a meta-analysis to obtain more precise estimates of the association between PPARGC1A Gly482Ser polymorphism and AA/SP.

Methods

Multi-database literature search yielded 14 articles (16 studies) for inclusion. Pooled odds ratios (ORs) and 95% confidence intervals (CI) were used to estimate associations. Summary effects were modified based on statistical power. Subgroup analysis was based on SP (power, endurance and mixed) and race (Caucasians and Asians). Heterogeneity was assessed with the I2 metric and its sources examined with outlier analysis which dichotomized our findings into pre- (PRO) and post-outlier (PSO).

Results

Gly allele effects significantly favoring AA/SP (OR > 1.0, P < 0.05) form the core of our findings in: (i) homogeneous overall effect at the post-modified, PSO level (OR 1.13, 95% CI 1.03–1.25, P = 0.01, I2 = 0%); (ii) initially homogeneous power SP (ORs 1.22–1.25, 95% CI 1.05–1.44, P = 0.003–0.008, I2 = 0%) which precluded outlier treatment; (iii) PRO Caucasian outcomes (ORs 1.29–1.32, 95% CI 1.12–1.54, P = 0.0005) over that of Asians with a pooled null effect (OR 0.99, 95% CI 0.72–1.99, P = 0.53–0.92) and (iv) homogeneous all > 80% (ORs 1.19–1.38, 95% CI 1.05–1.66, P = 0.0007–0.007, I2 = 0%) on account of high statistical power (both study-specific and combined). In contrast, none of the Ser allele effects significantly favored AA/SP and no Ser-Gly genotype outcome favored AA/SP. The core significant outcomes were robust and showed no evidence of publication bias.

Conclusion

Meta-analytical applications in this study generated evidence that show association between the Gly allele and AA/SP. These were observed in the overall, Caucasians and statistically powered comparisons which exhibited consistent significance, stability, robustness, precision and lack of bias. Our central findings rest on association of the Gly allele with endurance and power, differentially favoring the latter over the former.

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<![CDATA[The quest for an optimal alpha]]> https://www.researchpad.co/article/5c3667f0d5eed0c4841a6a36

Researchers who analyze data within the framework of null hypothesis significance testing must choose a critical “alpha” level, α, to use as a cutoff for deciding whether a given set of data demonstrates the presence of a particular effect. In most fields, α = 0.05 has traditionally been used as the standard cutoff. Many researchers have recently argued for a change to a more stringent evidence cutoff such as α = 0.01, 0.005, or 0.001, noting that this change would tend to reduce the rate of false positives, which are of growing concern in many research areas. Other researchers oppose this proposed change, however, because it would correspondingly tend to increase the rate of false negatives. We show how a simple statistical model can be used to explore the quantitative tradeoff between reducing false positives and increasing false negatives. In particular, the model shows how the optimal α level depends on numerous characteristics of the research area, and it reveals that although α = 0.05 would indeed be approximately the optimal value in some realistic situations, the optimal α could actually be substantially larger or smaller in other situations. The importance of the model lies in making it clear what characteristics of the research area have to be specified to make a principled argument for using one α level rather than another, and the model thereby provides a blueprint for researchers seeking to justify a particular α level.

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<![CDATA[Caveat emptor, computational social science: Large-scale missing data in a widely-published Reddit corpus]]> https://www.researchpad.co/article/5b4a289a463d7e4513b8980b

As researchers use computational methods to study complex social behaviors at scale, the validity of this computational social science depends on the integrity of the data. On July 2, 2015, Jason Baumgartner published a dataset advertised to include “every publicly available Reddit comment” which was quickly shared on Bittorrent and the Internet Archive. This data quickly became the basis of many academic papers on topics including machine learning, social behavior, politics, breaking news, and hate speech. We have discovered substantial gaps and limitations in this dataset which may contribute to bias in the findings of that research. In this paper, we document the dataset, substantial missing observations in the dataset, and the risks to research validity from those gaps. In summary, we identify strong risks to research that considers user histories or network analysis, moderate risks to research that compares counts of participation, and lesser risk to machine learning research that avoids making representative claims about behavior and participation on Reddit.

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<![CDATA[How Industry Uses the ICMJE Guidelines to Manipulate Authorship&#8212;And How They Should Be Revised]]> https://www.researchpad.co/article/5989da73ab0ee8fa60b95bf6

Based upon his 15 years of experience as a medical writer, Alastair Matheson argues that rather than obstructing industry, the current ICMJE authorship guidelines have become its preferred tool for misattributing authorship.

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<![CDATA[Financial Conflicts of Interest and Reporting Bias Regarding the Association between Sugar-Sweetened Beverages and Weight Gain: A Systematic Review of Systematic Reviews]]> https://www.researchpad.co/article/5989d9d4ab0ee8fa60b654f6

Maira Bes-Rastrollo and colleagues examine whether financial conflicts of interest are likely to bias conclusions from systematic reviews that investigate the relationship between sugar-sweetened beverages and weight gain or obesity.

Please see later in the article for the Editors' Summary

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<![CDATA[The Imperative to Share Clinical Study Reports: Recommendations from the Tamiflu Experience]]> https://www.researchpad.co/article/5989dabaab0ee8fa60bae708

Peter Doshi and colleagues describe their experience trying and failing to access clinical study reports from the manufacturer of Tamiflu and challenge industry to defend their current position of RCT data secrecy.

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<![CDATA[Getting Closer to a Fully Correctable and Connected Research Literature]]> https://www.researchpad.co/article/5989da6cab0ee8fa60b93258

The PLOS Medicine Editors discuss the need for a dynamic publishing system that enables linkage to corrections of errors in scientific literature (whatever their source) and full integration of articles with post-publication commentary.

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<![CDATA[A Systematic Review of Re-Identification Attacks on Health Data]]> https://www.researchpad.co/article/5989d9e4ab0ee8fa60b6a86a

Background

Privacy legislation in most jurisdictions allows the disclosure of health data for secondary purposes without patient consent if it is de-identified. Some recent articles in the medical, legal, and computer science literature have argued that de-identification methods do not provide sufficient protection because they are easy to reverse. Should this be the case, it would have significant and important implications on how health information is disclosed, including: (a) potentially limiting its availability for secondary purposes such as research, and (b) resulting in more identifiable health information being disclosed. Our objectives in this systematic review were to: (a) characterize known re-identification attacks on health data and contrast that to re-identification attacks on other kinds of data, (b) compute the overall proportion of records that have been correctly re-identified in these attacks, and (c) assess whether these demonstrate weaknesses in current de-identification methods.

Methods and Findings

Searches were conducted in IEEE Xplore, ACM Digital Library, and PubMed. After screening, fourteen eligible articles representing distinct attacks were identified. On average, approximately a quarter of the records were re-identified across all studies (0.26 with 95% CI 0.046–0.478) and 0.34 for attacks on health data (95% CI 0–0.744). There was considerable uncertainty around the proportions as evidenced by the wide confidence intervals, and the mean proportion of records re-identified was sensitive to unpublished studies. Two of fourteen attacks were performed with data that was de-identified using existing standards. Only one of these attacks was on health data, which resulted in a success rate of 0.00013.

Conclusions

The current evidence shows a high re-identification rate but is dominated by small-scale studies on data that was not de-identified according to existing standards. This evidence is insufficient to draw conclusions about the efficacy of de-identification methods.

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<![CDATA[Excess Success for Psychology Articles in the Journal Science]]> https://www.researchpad.co/article/5989dadbab0ee8fa60bb9a6c

This article describes a systematic analysis of the relationship between empirical data and theoretical conclusions for a set of experimental psychology articles published in the journal Science between 2005–2012. When the success rate of a set of empirical studies is much higher than would be expected relative to the experiments' reported effects and sample sizes, it suggests that null findings have been suppressed, that the experiments or analyses were inappropriate, or that the theory does not properly follow from the data. The analyses herein indicate such excess success for 83% (15 out of 18) of the articles in Science that report four or more studies and contain sufficient information for the analysis. This result suggests a systematic pattern of excess success among psychology articles in the journal Science.

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