Logical Fallacies and the Misuse of RCT Findings: Lessons from Diagnostic Statistics

Margaret MacDougall ()
Additional contact information
Margaret MacDougall: Edinburgh Medical School, Usher Institute

Chapter Chapter 3 in A Medical Educator's Guide to Thinking Critically about Randomised Controlled Trials: Deconstructing the "Gold Standard", 2024, pp 63-88 from Springer

Abstract: Abstract This chapter offers an excursion through many of the important analogies encountered on comparing the conceptual frameworks for diagnostic statistics and null hypothesis significance testing (NHST). We shall meet three common logical fallacies that can prove influential in overestimating the probability of an intervention being effective, given a statistically significant outcome in favour of the intervention. In keeping with previous work, this conditional probability will be referred to as the positive predictive value (PPV) of the hypothesis test for the given study hypothesis. Relatedly, we shall see how researchers can be duped into a false reliance on statistical significance from a single randomised controlled trial (RCT) as an indicator of the reputability of the study hypothesis, while overestimating, and neglecting the importance of, the PPV. Recognition of the need for a higher PPV points to the fallibility of the RCT, in keeping with other study designs, as a source of scientific truth. In addition to training students to recognise and circumvent common misapplications of conditional probabilities in diagnostic statistics and hypothesis testing, the content of this chapter warns against some misconceptions in traditional representations of the relationships between prevalence and diagnostic statistics in medical textbooks and related expository papers. While this ought to support modern teaching on the theme of diagnostic testing, the aim in view is that of preparing the way for consideration in Chap. 4 of the parameterisation and management of the PPV using Bayes’ rule specifically within the context of NHST.

Date: 2024
References: Add references at CitEc
Citations:

There are no downloads for this item, see the EconPapers FAQ for hints about obtaining it.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:spr:sprchp:978-3-031-25859-6_3

Ordering information: This item can be ordered from
http://www.springer.com/9783031258596

DOI: 10.1007/978-3-031-25859-6_3

Access Statistics for this chapter

More chapters in Springer Books from Springer
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().