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Index
Cover
Half Title
Title Page
Copyright Page
Dedication
Table of Contents
List of figures
List of tables
List of boxes
Acknowledgements
Part I Introduction
1 Evidence-based health research
Preliminary exercise and installing R
How to install the R program
Answers to the formative numeracy exercise using R
Further reading
PART II Critical numbers
2 Descriptive statistics part 1: levels of measurement and measures of central tendency
Intended learning outcomes
Introducing key terms
Levels of measurement
Why is determining the level of measurement important?
Are levels of measurement potentially misleading?
3 Descriptive statistics part 2: measures of dispersion
Intended learning outcomes
Mean
Sample and population mean
Median
Mode
Range
The normal distribution
Other kinds of distributions
Measures of dispersion
Transformations
Summary
4 Measures of association for categorical outcomes
Introduction
Intended learning outcomes
Risk and odds
Calculating absolute risk
Number needed to treat (NNT) and number needed to harm (NNH)
Odds ratios
Summary
5 Measures of association for continuous outcomes
Intended learning outcomes
Differences between two means
Summary
6 Confounding, effect modification, mediation and causal inference
Intended learning outcomes
Introducing key terms
Confounding variables
Effect modifying variables
Mediating variables
Antecedent variables
Causal variables
PART III Critical appraisal of existing research
7 Literature reviewing and database searching
Intended learning outcomes
Narrative reviews of the literature
Systematic reviews of the literature
Social networking approaches to searching the literature
Bibliographic software
Summary
Web links
8 Randomised controlled trials
Intended learning outcomes
Introducing key terms
A cognitive behavioural intervention to reduce sexually transmitted infections among gay men: randomised trial
Effect on smoking quit rate of telling patients their lung age: the Step2quit randomised controlled trial
Effect of physical activity on cognitive function in older adults at risk for Alzheimer’s disease: a randomised trial
Summary
9 Cohort studies
Intended learning outcomes
What are the essential features of a cohort study?
Environmental tobacco smoke and tobacco related mortality in a prospective study of Californians, 1960–98
Joint effect of cigarette smoking and alcohol consumption on mortality
Institutional risk factors for norovirus outbreaks in Hong Kong elderly homes: a retrospective cohort study
Cohorts do not need to represent populations: a note about internal and external validity of cohort studies
Summary
10 Case-control studies
Intended learning outcomes
What are the essential features of a case-control study?
Introducing key terms
Pet birds and risk of lung cancer in Sweden: a case-control study
Association between maternal sleep practices and risk of late stillbirth: a case-control study
Mobile phone use and brain tumors in children and adolescents: a multicentre case-control study
Summary
11 Research ethics and data management
Intended learning outcomes
Introducing key terms
Practical example of an IRAS application
Questionnaires
Data management
Summary
PART IV Conducting new research
12 Dissemination and publication
Intended learning outcomes
Types of published writing
The structure of original research articles
Choosing a journal
13 Linear regression for continuous outcomes
Intended learning outcomes
Introducing key terms
The linear regression equation
The method of least squares
Linear regression in R
What do the regression coefficients mean?
Interpreting the output
The F-statistic and equivalence to ANOVA
Standardising predictor variables
Regression using centred age
Multiple linear regression
Running a multiple regression in R
Hierarchical multiple regression
Categorical predictor variables
Adjusting for possible mediators to evaluate attenuation of an effect
Adding interaction terms to evaluate effect modification
R-squared
Checking assumptions
Transforming variables
Outcome variables with a preponderance of zeros
Non-normality in outcome variables
Standardised regression coefficients
Summary
Further reading
14 Logistic regression for categorical outcomes
Intended learning outcomes
Why linear regression is not suitable for dichotomous outcomes
Introducing logistic regression
Preparing for logistic regression
The logistic regression equation
Recap: log odds, odds, probability
Getting started with logistic regression
Results from a simple logistic regression model
Comparing the goodness of fit of two logistic regression models: loglikelihood test
Identifying whether a variable significantly improves fit of the model: Wald test
Obtaining predicted probabilities
Summary
Further reading
Appendix 1: Critical values for the t-test
Appendix 2: Critical values for the F-test
Appendix 3: Table of z-values
Appendix 4; T/U table for Mann Whitney U test
Appendix 5: Critical values for the Wilcoxon test
Appendix 6: Consent form
Appendix 7: Statistical power
Appendix 8: Validity and bias
Glossary
References
Index
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