Some time ago I wrote a post complaining that the New England Journal of Medicine was promoting testing of baseline characteristics in randomised trials, in their Instructions for Authors (post is here). After I wrote that I wondered if I was being fair; it could possibly refer to comparisons of outcomes, not baseline characteristics. The … Continue reading NEJM again
Maybe hilarity is a bit strong. I've just been looking at the recently published (in JAMA) Guidelines for the Content of Statistical Analysis Plans in Clinical Trials. Most of the action is in the eAppendix2 "Explanation and Elaboration of Essential Items," where they go through the essential items in exhaustive and sometimes mind-numbing detail. It's … Continue reading Unintentional hilarity in statistical analysis plan guidelines
Via Twitter, I came across a blog post by Dr John Mandrola (here) on the VEST trial, whose results have recently been presented at the American College of Cardiology Annual Scientific Session. The trial evaluated a wearable cardioverter-defibrillator in patients after myocardial infarction (conference abstract (without results) here). Dr Mandrola seems not to like the … Continue reading The Vest
This post arose from a discussion on Twitter about a recently-published randomised trial. Twitter isn’t the best forum for debate so I wanted to summarise my thoughts here in some more detail. What was interesting about the trial was that it used a Bayesian analysis, but this provoked a lot of reaction on Twitter that … Continue reading Bayesian trial in the real world
People often speak and write about values of treatment effects outside their confidence intervals as being “excluded.” For example; “the risk ratio for major morbidity was 0.98 (95% CI 0.91, 1.06), which excluded any clinically important effects.” I just made that up but you often see and hear similar statements. What understanding do people take from … Continue reading Language, confidence intervals and beliefs
I don't want to start obsessing about sample size calculations, because most of the time they're pretty pointless and irrelevant, but I came across a great one recently. My award for least logical sample size calculation goes to Mitesh Patel et al, Intratympanic methylprednisolone versus gentamicin in patients with unilateral Meniere's disease: a randomised, comparative … Continue reading Best sample size calculation ever!
I found a paper in a clinical journal about confidence intervals. I’m not going to give the reference, but it was published in 2017, and written by a group of clinicians and methodologists, including a statistician. Its main purpose was to explain confidence intervals to clinical readers – which is undoubtedly a worthwhile aim, as … Continue reading Confidence (again)