Determining Sample Size and Power in Research Studies

Determining Sample Size and Power in Research Studies
Title Determining Sample Size and Power in Research Studies PDF eBook
Author J. P. Verma
Publisher Springer Nature
Pages 138
Release 2020-07-20
Genre Mathematics
ISBN 9811552045

Download Determining Sample Size and Power in Research Studies Book in PDF, Epub and Kindle

This book addresses sample size and power in the context of research, offering valuable insights for graduate and doctoral students as well as researchers in any discipline where data is generated to investigate research questions. It explains how to enhance the authenticity of research by estimating the sample size and reporting the power of the tests used. Further, it discusses the issue of sample size determination in survey studies as well as in hypothesis testing experiments so that readers can grasp the concept of statistical errors, minimum detectable difference, effect size, one-tail and two-tail tests and the power of the test. The book also highlights the importance of fixing these boundary conditions in enhancing the authenticity of research findings and improving the chances of research papers being accepted by respected journals. Further, it explores the significance of sample size by showing the power achieved in selected doctoral studies. Procedure has been discussed to fix power in the hypothesis testing experiment. One should usually have power at least 0.8 in the study because having power less than this will have the issue of practical significance of findings. If the power in any study is less than 0.5 then it would be better to test the hypothesis by tossing a coin instead of organizing the experiment. It also discusses determining sample size and power using the freeware G*Power software, based on twenty-one examples using different analyses, like t-test, parametric and non-parametric correlations, multivariate regression, logistic regression, independent and repeated measures ANOVA, mixed design, MANOVA and chi-square.

The Health Effects of Cannabis and Cannabinoids

The Health Effects of Cannabis and Cannabinoids
Title The Health Effects of Cannabis and Cannabinoids PDF eBook
Author National Academies of Sciences, Engineering, and Medicine
Publisher National Academies Press
Pages 487
Release 2017-03-31
Genre Science
ISBN 0309453070

Download The Health Effects of Cannabis and Cannabinoids Book in PDF, Epub and Kindle

Significant changes have taken place in the policy landscape surrounding cannabis legalization, production, and use. During the past 20 years, 25 states and the District of Columbia have legalized cannabis and/or cannabidiol (a component of cannabis) for medical conditions or retail sales at the state level and 4 states have legalized both the medical and recreational use of cannabis. These landmark changes in policy have impacted cannabis use patterns and perceived levels of risk. However, despite this changing landscape, evidence regarding the short- and long-term health effects of cannabis use remains elusive. While a myriad of studies have examined cannabis use in all its various forms, often these research conclusions are not appropriately synthesized, translated for, or communicated to policy makers, health care providers, state health officials, or other stakeholders who have been charged with influencing and enacting policies, procedures, and laws related to cannabis use. Unlike other controlled substances such as alcohol or tobacco, no accepted standards for safe use or appropriate dose are available to help guide individuals as they make choices regarding the issues of if, when, where, and how to use cannabis safely and, in regard to therapeutic uses, effectively. Shifting public sentiment, conflicting and impeded scientific research, and legislative battles have fueled the debate about what, if any, harms or benefits can be attributed to the use of cannabis or its derivatives, and this lack of aggregated knowledge has broad public health implications. The Health Effects of Cannabis and Cannabinoids provides a comprehensive review of scientific evidence related to the health effects and potential therapeutic benefits of cannabis. This report provides a research agendaâ€"outlining gaps in current knowledge and opportunities for providing additional insight into these issuesâ€"that summarizes and prioritizes pressing research needs.

Research Methods for Organizational Studies

Research Methods for Organizational Studies
Title Research Methods for Organizational Studies PDF eBook
Author Donald P. Schwab
Publisher Psychology Press
Pages 320
Release 2013-06-17
Genre Business & Economics
ISBN 1135704910

Download Research Methods for Organizational Studies Book in PDF, Epub and Kindle

This revision of a best selling research methods textbook introduces social science methods as applied broadly to the study of issues that arise as part of organizational life. These include issues involving organizational participants such as managers, teachers, customers, patients and clients, and transactions within and between organizations. In this new edition, chapter 19 now focuses on describing the modeling process and outcomes. An entirely new chapter 20 now addresses challenges to modeling. It goes substantially beyond a discussion of statistical inference. It also discusses issues in interpreting variance, explained estimates, and standardized and unstandardized regression coefficients. A new capstone chapter 21 helps students recognize good research. This textbook is accompanied by an Instructor's Manual for course use.

Women and Health Research

Women and Health Research
Title Women and Health Research PDF eBook
Author Institute of Medicine
Publisher National Academies Press
Pages 286
Release 1994-02-01
Genre Medical
ISBN 030904992X

Download Women and Health Research Book in PDF, Epub and Kindle

In the nineteenth century some scientists argued that women should not be educated because thinking would use energy needed by the uterus for reproduction. The proof? Educated women had a lower birth rate. Today's researchers can only shake their heads at such reasoning. Yet professional journals and the popular press are increasingly criticizing medical research for ignoring women's health issues. Women and Health Research examines the facts behind the public's perceptions about women participating as subjects in medical research. With the goal of increasing researchers' awareness of this important topic, the book explores issues related to maintaining justice (in its ethical sense) in clinical studies. Leading experts present general principles for the ethical conduct of research on womenâ€"principles that are especially important in the light of recent changes in federal policy on the inclusion of women in clinical research. Women and Health Research documents the historical shift from a paternalistic approach by researchers toward women and a disproportionate reliance on certain groups for research to one that emphasizes proper access for women as subjects in clinical studies in order to ensure that women receive the benefits of research. The book addresses present-day challenges to equity in four areas: Scientificâ€"Do practical aspects of scientific research work at cross-purposes to gender equity? Focusing on drug trials, the authors identify rationales for excluding people from research based on demographics. Social and Ethicalâ€"The authors offer compelling discussions on subjectivity in science, the evidence for male bias, and issues related to race and ethnicity, as well as the recruitment, retention, and protection of research participants. Legalâ€"Women and Health Research reviews federal research policies that affect the inclusion of women and evaluates the basis for researchers' fears about liability, citing court cases. Riskâ€"The authors focus on risks to reproduction and offspring in clinical drug trials, exploring how risks can be identified for study participants, who should make the assessment of risk and benefit for participation in a clinical study, and how legal implications could be addressed. This landmark study will be of immediate use to the research community, policymakers, women's health advocates, attorneys, and individuals.

Reproducibility and Replicability in Science

Reproducibility and Replicability in Science
Title Reproducibility and Replicability in Science PDF eBook
Author National Academies of Sciences, Engineering, and Medicine
Publisher National Academies Press
Pages 257
Release 2019-10-20
Genre Science
ISBN 0309486165

Download Reproducibility and Replicability in Science Book in PDF, Epub and Kindle

One of the pathways by which the scientific community confirms the validity of a new scientific discovery is by repeating the research that produced it. When a scientific effort fails to independently confirm the computations or results of a previous study, some fear that it may be a symptom of a lack of rigor in science, while others argue that such an observed inconsistency can be an important precursor to new discovery. Concerns about reproducibility and replicability have been expressed in both scientific and popular media. As these concerns came to light, Congress requested that the National Academies of Sciences, Engineering, and Medicine conduct a study to assess the extent of issues related to reproducibility and replicability and to offer recommendations for improving rigor and transparency in scientific research. Reproducibility and Replicability in Science defines reproducibility and replicability and examines the factors that may lead to non-reproducibility and non-replicability in research. Unlike the typical expectation of reproducibility between two computations, expectations about replicability are more nuanced, and in some cases a lack of replicability can aid the process of scientific discovery. This report provides recommendations to researchers, academic institutions, journals, and funders on steps they can take to improve reproducibility and replicability in science.

Handbook of EHealth Evaluation

Handbook of EHealth Evaluation
Title Handbook of EHealth Evaluation PDF eBook
Author Francis Yin Yee Lau
Publisher
Pages 487
Release 2016-11
Genre Medical care
ISBN 9781550586015

Download Handbook of EHealth Evaluation Book in PDF, Epub and Kindle

To order please visit https://onlineacademiccommunity.uvic.ca/press/books/ordering/

The Design of Studies for Medical Research

The Design of Studies for Medical Research
Title The Design of Studies for Medical Research PDF eBook
Author David Machin
Publisher John Wiley & Sons
Pages 286
Release 2005-05-13
Genre Medical
ISBN 0470012986

Download The Design of Studies for Medical Research Book in PDF, Epub and Kindle

The same careful rigour imposed on the design of phase III randomised controlled trials is not always applied to medical research in other areas such as trials conducted at earlier stages of drug development. With the emphasis that is now placed on evidence-based medicine, such care and rigour will inevitably impact on these areas with increasing attention turned to the quality of design. This title describes what principles can be used to structure research effectively allowing for the required degree of accuracy. Written by two best selling authors, this book includes many examples from medical literature and will be of great value to all groups conducting studies at the interface of clinical and laboratory research.