### Heterogeneity: what is it and why does it matter?

This blog examines what heterogeneity is, why it matters, how you can identify and measure it and how you can then deal with it.

Tutorials and Fundamentals

This blog examines what heterogeneity is, why it matters, how you can identify and measure it and how you can then deal with it.

Tutorials and Fundamentals

This blog, written by Leonard Goh, was the winner of Cochrane Malaysia and Penang Medical College’s recent evidence-based medicine blog writing competition. Leonard has written an insightful and informative piece to answer the question: ‘Evidence-based health practice: a fairytale or reality’.

Tutorials and Fundamentals

This blog follows on from Ammar’s previous post on meta-analysis, and provides further details on the history, value and implementation of this approach.

Tutorials and Fundamentals

This blog provides an introduction to sample size and power; what it is, why it’s important to consider when designing a study, and how to carry out a power calculation.

Tutorials and Fundamentals

This blog discusses fundamental issues affecting healthcare research, which could undermine the field and mean that most medical research may be wrong. Issues discussed include: 1) contradictory findings 2) the illusion of high impact factor journals 3) the reproducibility crisis 4) a lack of translation of research findings from bench to bedside 5) medical reversal 6) bias 7) statistical issues and 8) conflicts of interest and unethical practice. The author then explores possible solutions to these.

Tutorials and Fundamentals

‘Evidence-based practice’ is a commonly used phrase. But this blog asks the question: ‘just how much can we trust published scientific literature?’ with particular reference to the problems of publication bias and statistical approaches.

Tutorials and Fundamentals

This blog explains what is meant by Type I and Type II errors in statistics. Whereby we can end up with false positive and false negative results.

Tutorials and Fundamentals

This blog uses 3 examples to demonstrate that, even though there may be an association between two events or variables, this does not mean that one has caused the other.

Tutorials and Fundamentals

A nuts and bolts tutorial on how to read a forest plot, featuring a couple of exercises so that you can test your own understanding.

Tutorials and Fundamentals

Let’s figure out how to get the essential information from a meta-analysis at a glance, by studying a forest plot.

Tutorials and Fundamentals

Median has come to be known for its fair reflection in the case of outliers. However, it is not a perfect statistic. Let me tell you about 3 defects the median as a measure of average.

Tutorials and Fundamentals

Come with me. I’ll show you the best way to display the efficacy of a drug. And the pitfalls around it. Ladies and gentlemen, welcome to the world of Number needed to treat.

Tutorials and Fundamentals

Confused about Hazard Ratios and their confidence intervals? This blog provides a handy tutorial.

Tutorials and Fundamentals

This post talks about the real meaning of p-value. No fancy words. No complicated definitions. Only simple notions included.

Tutorials and Fundamentals

How can you tell if a variable is nominal, ordinal, or numerical? Why does it even matter? Determining the appropriate variable type used in a study is essential to determining the correct statistical method to use when obtaining your results. It is important not to take the variables out of context because more often than not, the same variable that can be ordinal can also be numerical, depending on how the data was recorded and analyzed. This post will give you a specific example that may help you better grasp this concept.

Learning Resources

Know Your Chances: Understanding Health Statistics is one of the few easily digestible statistics books that teaches anyone the most basic principles and concepts how to question and see the reality behind health news, hype, claims and ads.

Tutorials and Fundamentals

As calculating the mean is so popular it might lead to many intuitive misconceptions. Here are some precautions you can take when interpreting the mean.

Tutorials and Fundamentals

Terms such as significant, hypothesis testing, and p-value are usually found in research papers, here is a review explaining them.

Learning Resources

In search of a book with simple, comprehensible definitions and examples of clinical evidence? Do you want to take the first step in understanding common terms in clinical evidence as well as commonly used methods and their pitfalls? This review will inform you if this is the book you’re looking for.

Learning Resources

Is this your first contact with evidence-based healthcare? This course is a perfect start…

Learning Resources

Sean reviews the Statistics Learning Centre’s Videos – a Youtube channel featuring a series of free tutorials which aim to help you learn the concepts of statistics from identifying types of data to performing t-tests in Excel.

Tutorials and Fundamentals

Sean reviews ‘What is Evidence Based Medicine and Why Should I care?’, an article for students and healthcare professionals which covers Evidence-Based Medicine from first principles to medical statistics in the course of one free paper.

Learning Resources

Danny has reviewed Testing Treatments Interactive, a website to help you understand more about fair tests and research.

Tutorials and Fundamentals

An introduction to the role of statistical power in the search for evidence.

Tutorials and Fundamentals

The nuts and bolts 20 minute tutorial from Tim.

Tutorials and Fundamentals

Systematic reviews aren’t cheap or quick – Alice looks at some suggestions from the blogs of Jon Brassey from TRIP and Mona Nasser from Cochrane.

Learning Resources

Revealing the truth behind rates, ratios and risk with QMP statistics tutorials. This is one of a series that helps with understanding of statistics and study design.

Learning Resources

Understanding uncertainty is a site from the Winton programme based at the University of Cambridge, UK, that encourage healthy criticism of the statistics the media gives us.

Learning Resources

QMP Statistics tutorials talks you through chi-squared and t-tests – a useful resource for different statistical levels.

Tutorials and Fundamentals

Conducting trials where the trialled therapeutic must be commenced urgently raises specific practical and ethical problems. Here I discuss a recent New England Journal of Medicine paper looking at the use of intracranial pressure monitoring for severe traumatic brain injury as an example of how these issues may affect a trial’s utility and how this can be managed.

Evidence Reviews

David explains risk and number needed to treat using an article from the New England Journal of Medicine

Learning Resources

Need something for your EBM task? Check out EBHC wiki!! You will find it there..

Learning Resources

Dr Cates provides easy to read re-freshers on statistics and EBM topics

Learning Resources

This tutorial teaches the essentials about the statistics in medicine and covers various aspects of normal distribution (ND): central limit theorem, properties of ND, NDs with different means and with different variances, variables that follow a ND, normal plot and introduction to t-distribution

Learning Resources

A must-have tutorial on how to critically appraise research.

Learning Resources

QMP Medical Statistics Tutorials are a great place to start learning about the principles of evidence-based medicine. The probability & significance test, in my opinion, should be one of the first tutorials for a medical student.

Learning Resources

This tutorial teaches you about one of the biggest enemies of strong evidence in clinical research – bias, as well as measurements and outcomes in the clinical trial.

Learning Resources

A review of an evaluating risk online course for 11 – 16 year olds, by our youngest blogger Liv!

Learning Resources

A short article on the uses of Facebook friend finder…

Tutorials and Fundamentals

Beginners often get confused with odds ratio and relative risk, which are almost used in same sense.

A simple way to understand both.

Learning Resources

The QMP Medical Statistics tutorial that is designed to show you how to apply evidence-based medicine to clinical practice in a practical and logical manner.

Learning Resources

Statistically funny – the blog that combines cartoons, humour, and demystifying evidence-based medicine.

Learning Resources

This tutorial covers how to use appropriate statistical tests and what are confidence intervals and how do you use them.

Learning Resources

This is a tutorial that looks at the statistical basis of randomised controlled trials, the theory behind meta-analyses and how to read a meta-analysis

Learning Resources

This is an information skills tutorial that provides the opportunity for students to learn more about searching for information

Learning Resources

A good website from the Centre for Evidence-Based Medicine (CEBM) – with a wide range of tools to help with evidence-based research

Learning Resources

The BMJ has on its website a series of articles on how to read papers, including clear explanations of the statistics commonly used and common pitfalls found in studies.

Learning Resources

This is a short, clearly written tutorial explaining the basic concepts of evidence-based medicine.

Learning Resources

A short poem about regression to the mean illustrated with a few examples!

Learning Resources

SPSS is a computer program used for statistical analysis. This tutorial will take you through a series of activities to help improve your SPSS skills.

Learning Resources

In this medical statistics tutorial we will be looking at how the data that are collected by studies are summarized and presented in order to extract useful information. We will then start to look at how to analyse the data.

Learning Resources

This interactive online course on ‘making sense of research & evidence’, assumes no previous knowledge of research or evidence-based medicine.

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