Book contents
- Evidence-Based Diagnosis
- Evidence-Based Diagnosis
- Copyright page
- Dedication
- Contents
- Preface
- Acknowledgments
- Chapter 1 Introduction
- Chapter 2 Dichotomous Tests
- Chapter 3 Multilevel and Continuous Tests
- Chapter 4 Critical Appraisal of Studies of Diagnostic Test Accuracy
- Chapter 5 Reliability and Measurement Error
- Chapter 6 Risk Predictions
- Chapter 7 Multiple Tests and Multivariable Risk Models
- Chapter 8 Quantifying Treatment Effects Using Randomized Trials
- Chapter 9 Alternatives to Randomized Trials for Estimating Treatment Effects
- Chapter 10 Screening Tests
- Chapter 11 Understanding P-Values and Confidence Intervals
- Chapter 12 Challenges for Evidence-Based Diagnosis
- Answers to Problems
- Index
- References
Chapter 11 - Understanding P-Values and Confidence Intervals
Published online by Cambridge University Press: 02 May 2020
Book contents
- Evidence-Based Diagnosis
- Evidence-Based Diagnosis
- Copyright page
- Dedication
- Contents
- Preface
- Acknowledgments
- Chapter 1 Introduction
- Chapter 2 Dichotomous Tests
- Chapter 3 Multilevel and Continuous Tests
- Chapter 4 Critical Appraisal of Studies of Diagnostic Test Accuracy
- Chapter 5 Reliability and Measurement Error
- Chapter 6 Risk Predictions
- Chapter 7 Multiple Tests and Multivariable Risk Models
- Chapter 8 Quantifying Treatment Effects Using Randomized Trials
- Chapter 9 Alternatives to Randomized Trials for Estimating Treatment Effects
- Chapter 10 Screening Tests
- Chapter 11 Understanding P-Values and Confidence Intervals
- Chapter 12 Challenges for Evidence-Based Diagnosis
- Answers to Problems
- Index
- References
Summary
In the previous two chapters, we discussed using the results of randomized trials and observational studies to estimate treatment effects. We were primarily interested in measures of effect size and in problems with design (in randomized trials) and confounding (in observational studies) that could bias effect estimates. We did not focus on whether the apparent treatment effects could be a result of chance or attempt to quantify the precision of our effect estimates. The statistics used to help us with these issues − P-values and confidence intervals – are the subject of this chapter.
- Type
- Chapter
- Information
- Evidence-Based DiagnosisAn Introduction to Clinical Epidemiology, pp. 280 - 302Publisher: Cambridge University PressPrint publication year: 2020
References
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