Unsuccessful Treatments of “Writer's Block”: A Meta-Analysis

2014 ◽  
Vol 115 (1) ◽  
pp. 276-278 ◽  
Author(s):  
Derrick C. McLean ◽  
Benjamin R. Thomas
Keyword(s):  
Meta Analysis ◽  
Small Sample ◽  
The Body ◽  
Effect Sizes ◽  
Sample Sizes ◽  
Writer's Block ◽  
Unsuccessful Treatment ◽  
Group Treatments ◽  
Writer’S Block ◽  
Small Sample Sizes

A wide literature of the unsuccessful treatment of writer's block has emerged since the early 1970's. Findings within this literature seem to confer generalizability of this procedure; however, small sample sizes may limit this interpretation. This meta-analysis independently analyzed effect sizes for “self-treatments” and “group-treatments” using number of words in the body of the publication as indication of a failure to treat writer's block. Results of the reported findings suggest that group-treatments tend to be slightly more unsuccessful than self-treatments.

scholarly journals Looking for crumbs in the obesity forest: anti-obesity interventions in the Mexican population. History, and systematic review with Meta-Analysis

2021 ◽  
Author(s):  
Esperanza M. Garcia-Oropesa ◽  
Yoscelina E. Martinez-Lopez ◽  
Sonia Maria Ruiz-Cejudo ◽  
Jose Dario Martinez-Ezquerro ◽  
Alvaro Diaz-Badillo ◽  
...  
Keyword(s):  
Systematic Review ◽  
Blood Pressure ◽  
Waist Circumference ◽  
Behavioral Interventions ◽  
Meta Analysis ◽  
Small Sample ◽  
Population History ◽  
Sample Sizes ◽  
Obesity And Diabetes ◽  
Small Sample Sizes

Mexicans and Mexican Americans share culture, genetic background, and predisposition for chronic complications associated with obesity and diabetes making imperative efficacious treatments and prevention. Obesity has been treated for centuries focused-on weight loss while other treatments on associated conditions like gout, diabetes (T2D), and hypertriglyceridemia. To date, there is no systematic review that synthetize the origin of obesity clinics in Mexico and the efforts to investigate treatments for obesity tested by randomized clinical trials (RCT). We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve anti-obesity RCT through 2019 and without inferior temporal limit. The systematic review included RCT of anti-obesity treatments in the Mexican adult population, including alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions reporting biometric outcomes such as BMI, weight, waist circumference, triglycerides, glucose, among others. Studies with at least three months of treatment were included in the meta-analysis. We found 634 entries, after removal of duplicates and screening the studies based on eligibility criteria, we analyzed 43, and 2 multinational-collaborative studies. Most of the national studies have small sample sizes, and the studied strategies do not have replications in the population. The nutrition/behavioral interventions were difficult to blind, and most studies have medium to high risk of bias. Nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like plain water instead of sweet beverages decrease triglycerides and systolic blood pressure. Participants with obesity and hypertension can have benefic effects with antioxidants, and treatment with insulin increase weight in those with T2D. The study of obesity in Mexico has been on-going for more than four decades, but the interest on RCT just increased until this millennium, but with small sample sizes and lack of replication. The interventions affect different metabolic syndrome components, which should be analyzed in detail with the population living on the U.S.-Mexico border; therefore, bi-national collaboration is desirable to disentangle the cultural effects on this population's treatment response.

scholarly journals A Meta-Analysis Shows That Screen Bottom Boards Can Significantly Reduce Varroa destructor Population

Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 624
Author(s):  
Fang Liu ◽  
Xinjian Xu ◽  
Yuan Zhang ◽  
Hongxia Zhao ◽  
Zachary Y. Huang
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Varroa Destructor ◽  
Negative Impact ◽  
Meta Analysis ◽  
Small Sample ◽  
Effect Sizes ◽  
Negative Results ◽  
Mite Control ◽  
Small Sample Sizes

Varroa destructor is by far the most serious threat to the western honey bee, Apis mellifera. A screen bottom board, a cultural method for mite control, is a modified bottom board with a screen that allows mites to fall onto a sticky board, or the grass or soil below the screen. Whether or not a screen bottom board can reduce varroa significantly has been controversial. Most studies show a trend of lower varroa populations in colonies with these boards, but the results are usually not statistically significant. To understand whether the negative results have been due to small sample sizes, or because the board is actually ineffective, we conducted a meta-analysis with seven published studies with a total of 145 colonies. Meta-analysis showed that the confidence intervals of the combined effect sizes were negative with a Hedges’ g of −1.09 (SE 0.39, 95% CI −2.0 to −0.19, p < 0.01), which suggests that the varroa population in colonies with screen bottom boards is significantly lower compared to those with traditional wooden floors. We thus conclude that the screen bottom board does have a significantly negative impact on the varroa population and can be part of tool kits for mite control.

The Relationship Between Sample Sizes and Effect Sizes in Systematic Reviews in Education

2009 ◽  
Vol 31 (4) ◽  
pp. 500-506 ◽  
Author(s):  
Robert Slavin ◽  
Dewi Smith
Keyword(s):  
Sample Size ◽  
Effect Size ◽  
Secondary Mathematics ◽  
Significant Negative Correlation ◽  
Small Sample ◽  
Effect Sizes ◽  
Sample Sizes ◽  
Large Samples ◽  
Small Sample Sizes ◽  
The Relationship

Research in fields other than education has found that studies with small sample sizes tend to have larger effect sizes than those with large samples. This article examines the relationship between sample size and effect size in education. It analyzes data from 185 studies of elementary and secondary mathematics programs that met the standards of the Best Evidence Encyclopedia. As predicted, there was a significant negative correlation between sample size and effect size. The differences in effect sizes between small and large experiments were much greater than those between randomized and matched experiments. Explanations for the effects of sample size on effect size are discussed.

scholarly journals The Use of Glycomacropeptide in Patients with Phenylketonuria: A Systematic Review and Meta-Analysis

Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1794 ◽  
Author(s):  
Maria Pena ◽  
Alex Pinto ◽  
Anne Daly ◽  
Anita MacDonald ◽  
Luís Azevedo ◽  
...  
Keyword(s):  
Amino Acids ◽  
Meta Analysis ◽  
Small Sample ◽  
The Body ◽  
Intact Protein ◽  
Patient Acceptability ◽  
Native Form ◽  
Bias Risk ◽  
Small Sample Sizes ◽  
Limiting Amino Acids

In phenylketonuria (PKU), synthetic protein derived from L-amino acids (AAs) is essential in a low-phenylalanine (Phe) diet. Glycomacropeptide (GMP), an intact protein, is very low in Phe in its native form. It has been modified and adapted for PKU to provide an alternative protein source through supplementation with rate-limiting amino acids (GMP-AAs), although it still contains residual Phe. This review aims to systematically evaluate published intervention studies on the use of GMP-AAs in PKU by considering its impact on blood Phe control (primary aim) and changes in tyrosine control, nutritional biomarkers, and patient acceptability or palatability (secondary aims). Four electronic databases were searched for articles published from 2007 to June 2018. Of the 274 studies identified, only eight were included. Bias risk was assessed and a quality appraisal of the body of evidence was completed. A meta-analysis was performed with two studies with adequate comparable methodology which showed no differences between GMP-AAs and AAs for any of the interventions analysed. This work underlines the scarcity and nature of studies with GMP-AAs interventions. All were short-term with small sample sizes. There is a need for better-designed studies to provide the best evidence-based recommendations.

scholarly journals Human Papillomavirus in Sinonasal Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Cancers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 45
Author(s):  
Kim J. W. Chang Sing Pang ◽  
Taha Mur ◽  
Louise Collins ◽  
Sowmya R. Rao ◽  
Daniel L. Faden
Keyword(s):  
Systematic Review ◽  
Human Papillomavirus ◽  
Squamous Cell ◽  
Meta Analysis ◽  
Small Sample ◽  
Squamous Cell Carcinomas ◽  
Causative Role ◽  
Sample Sizes ◽  
Geographic Regions ◽  
Small Sample Sizes

Human papillomavirus (HPV) drives tumorigenesis in a subset of oropharyngeal squamous cell carcinomas (OPSCC) and is increasing in prevalence across the world. Mounting evidence suggests HPV is also involved in a subset of sinonasal squamous cell carcinomas (SNSCC), yet small sample sizes and variability of HPV detection techniques in existing literature hinder definitive conclusions. A systematic review was performed by searching literature through March 29th 2020 using PubMed, Embase, and Web of Science Core Collection databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed by two authors independently. A meta-analysis was performed using the random-effects model. Sixty studies (n = 1449) were eligible for statistical analysis estimating an overall HPV prevalence of 25.5% (95% CI 20.7–31.0). When stratified by HPV detection method, prevalence with multiple substrate testing (20.5%, 95% CI 14.5–28.2) was lower than with single substrate testing (31.7%, 95% CI 23.6–41.1), highest in high-exposure anatomic subsites (nasal cavity and ethmoids) (37.6%, 95% CI 26.5–50.2) vs. low-exposure (15.1%, 95% CI 7.3–28.6) and highest in high HPV+ OPSCC prevalence geographic regions (North America) (30.9%, 95% CI 21.9–41.5) vs. low (Africa) (13.1, 95% CI 6.5–24.5)). While small sample sizes and variability in data cloud firm conclusions, here, we provide a new reference point prevalence for HPV in SNSCC along with orthogonal data supporting a causative role for virally driven tumorigenesis, including that HPV is more commonly found in sinonasal subsites with increased exposure to refluxed oropharyngeal secretions and in geographic regions where HPV+ OPSCC is more prevalent.

Thymidylate Synthase Expression and Prognosis in Colorectal Cancer: A Systematic Review and Meta-Analysis

2004 ◽  
Vol 22 (3) ◽  
pp. 529-536 ◽  
Author(s):  
Sanjay Popat ◽  
Athena Matakidou ◽  
Richard S. Houlston
Keyword(s):  
Colorectal Cancer ◽  
Overall Survival ◽  
Thymidylate Synthase ◽  
Meta Analysis ◽  
Prognostic Significance ◽  
Progression Free Survival ◽  
Small Sample ◽  
Sample Sizes ◽  
Free Survival ◽  
Small Sample Sizes

Purpose A number of studies have investigated the relationship between thymidylate synthase (TS) expression and survival in colorectal cancer (CRC) patients. Although most have reported poorer overall and progression-free survival with high TS expression, estimates of the hazard ratio (HR) between studies differ wildly. To derive a more precise estimate of the prognostic significance of TS expression, we have reviewed published studies and carried out a meta-analysis. Materials and Methods Twenty studies stratifying overall survival and/or progression-free survival in CRC patients by TS expression status were eligible for analysis. The principal outcome measure was the HR. Data from these studies were pooled using standard meta-analysis techniques. Results Thirteen studies investigated outcome in a total of 887 cases with advanced CRC, and seven studies investigated outcome in a total of 2,610 patients with localized CRC. A number of methods were used both to assess TS expression and to assign TS status. Sample sizes varied greatly, small sample sizes being a feature of the advanced disease studies. The combined HR estimate for overall survival (OS) was 1.74 (95% CI, 1.34 to 2.26) and 1.35 (95% CI, 1.07 to 1.80) in the advanced and adjuvant settings, respectively, but there was evidence of heterogeneity and possible publication bias. Conclusion Tumors expressing high levels of TS appeared to have a poorer OS compared with tumors expressing low levels. Additional studies with consistent methodology are needed to define the precise prognostic value of TS.

scholarly journals A Comparative Study of the Nonlinear Methods for Estimate Body Weight by Body Measurements on Different Sample Sizes in Morkaraman Sheeps

2021 ◽  
Author(s):  
Mutlu YAGANOGLU
Keyword(s):  
Body Weight ◽  
Correlation Analysis ◽  
Body Length ◽  
Growth Models ◽  
Nonlinear Models ◽  
Small Sample ◽  
The Body ◽  
Body Measurements ◽  
Sample Sizes ◽  
Small Sample Sizes

Abstract The objective of this study was to estimate body weight of Morkaraman sheeps from body measurements with nonlinear models. Selected 110 sheeps 3-5 years were scored for body weight, body length, height at wither, chest width and pump width. For determine relationships with body weight between body measurements, correlation analysis was performed. The results of the correlation analysis indicated that the highest relationship according to the all sample sizes were body weight between body length (0.95, 0.90, 0.83, 0.81). Considering all parameters included in the model, the parameter showing the highest correlation with body weight was determined as body length according to all sample sizes. the highest correlation was found in 50 sample sizes (r:0.95). According to the small sample sizes (10-20), Logistic and Saturation growth models can be used to determine the body weight by using body length, on the other hand, Incomplete gamma model is more succesful to estimate body weight when sample size is nearly 30 and 50.

scholarly journals How to be Successful in Football: A Systematic Review

2018 ◽  
Vol 11 (1) ◽  
pp. 3-23 ◽  
Author(s):  
Hannes Lepschy ◽  
Hagen Wäsche ◽  
Alexander Woll
Keyword(s):  
Performance Indicators ◽  
Success Factors ◽  
Small Sample ◽  
The Body ◽  
Future Research ◽  
Sample Sizes ◽  
Situational Variables ◽  
Critical Success ◽  
Small Sample Sizes

Background:Despite the popularity of football, the analysis of success factors in football remains a challenge. While reviews on performance indicators in football are available, none focuses solely on the identification of success factors and addresses the large and growing body of recent research up until 2016.Objective:To find out what determines success in football and to organize the body of literature, a systematic literature review analyzing existing studies with regard to success factors in football was undertaken.Methods:The studies included in this review had to deal with performance indicators related to success in football. The studies were published in 2016 or before. The initial search revealed 19,161 articles. Finally, sixty-eight articles were included in this review. The studies were clustered with regard to comparative analyses, predictive analyses and analyses of home advantage.Results:In total, 76 different variables were investigated in the reviewed papers. It appeared that the most significant variables are efficiency (number of goals divided by the number of shots), shots on goal, ball possession, pass accuracy/successful passes as well as the quality of opponent and match location. Moreover, new statistical methods were used to reveal interactions among these variables such as discriminant analysis, factor analysis and regression analysis. The studies showed methodological deficits such as clear operational definitions of investigated variables and small sample sizes.Conclusion:The review allows a comprehensive identification of critical success factors in football and sheds light on utilized methodological approaches. Future research should consider precise operational definitions of the investigated variables, adequate sample sizes and the involvement of situational variables as well as their interaction.

scholarly journals Power Analysis for Conjoint Experiments

2020 ◽  
Author(s):  
Julian Schuessler ◽  
Markus Freitag
Keyword(s):  
Power Analysis ◽  
R Package ◽  
Small Sample ◽  
Effect Sizes ◽  
Sample Sizes ◽  
Social Scientists ◽  
Standard Tool ◽  
Sample Size Planning ◽  
Small Sample Sizes ◽  
Power Analyses

Conjoint experiments aiming to estimate average marginal component effects and related quantities have become a standard tool for social scientists. However, existing solutions for power analyses to find appropriate sample sizes for such studies have various shortcomings and accordingly, explicit sample size planning is rare. Based on recent advances in statistical inference for factorial experiments, we derive simple yet generally applicable formulae to calculate power and minimum required sample sizes for testing average marginal component effects (AMCEs), conditional AMCEs, as well as interaction effects in forced-choice conjoint experiments. The only input needed are expected effect sizes. Our approach only assumes random sampling of individuals or randomization of profiles and avoids any parametric assumption. Furthermore, we show that clustering standard errors on individuals is not necessary and does not affect power. Our results caution against designing conjoint experiments with small sample sizes, especially for detecting heterogeneity and interactions. We provide an R package that implements our approach.

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