Medical tests consume considerable resources and yet making requests is often left to the most junior members of the team. Medical schools often under prepare junior doctors for these tasks so they tend to request large numbers of tests to make sure 'all bases are covered' by the time a more senior colleague attends to the patient.
Beginning with naïve questions such as 'what is a medical test?' and 'why do we perform tests?', the book also covers the evaluation of tests from a public health perspective and helps the readers to determine whether a test should be introduced into clinical care. By describing the basics of medical decision making based on probability thresholds, students will learn how to avoid unnecessary testing when results are unlikely to influence patient relevant decisions, and the pros and cons of using metrics such as sensitivity, specificity, and predictive values.
Illustrated throughout with real life examples from multiple medical and surgical specialties, it concludes with a novel checklist for doctors to consider every time they think of requesting a test.
Written by a clinician for clinicians, this book is ideal for medical students and junior doctors. It provides everything they need to know to become experts at requesting tests. It will support them in requesting the most appropriate and effective tests, and inform them on how to interpret results, improving patients' outcomes.
Author(s): Tom Boyles
Publisher: Oxford University Press
Year: 2023
Language: English
Pages: 121
City: Oxford
Cover
How to Request a Test
Copyright
Dedication
Contents
Abbreviations
1. Introduction
2. Determining the Accuracy of a Test
3. Test Accuracy, Sensitivity, and Specificity
4. Test Accuracy As Positive and Negative Predictive Values
5. Test Accuracy As Likelihood Ratios
6. Decision Thresholds
7. Frameworks for Evaluating Medical Tests
8. Diagnostic and Prognostic Research
9. Impact Studies
10. Evaluation of a Novel Test
11. Conclusions
Appendix 1: The Reverend Thomas Bayes and the Monty Hall Problem
Appendix 2: Updating Probabilities Using Bayes’ Theorem
Appendix 3: Therapeutic Threshold
Appendix 4: Critical Appraisal of Boehme et al N Engl J Med 2010
Further Reading
Index