But first, take a look at this figure for what superiority trials aim to assess: What’s better?
2/ So how are NON-inferiority trials different?
They ask if a treatment is much worse than standard of care.
3/ Let’s look at the possible outcomes of a non-inferiority trial.
✔️Superior and non-inferior
✔️Non-inferior
✔️Not non-inferior
✔️Inferior and not non-inferior
✔️Inferior and non-inferior
4/ To close, why do a non-inferiority trial?
✅There is an accepted std of care, so placebo controlled may be unethical
✅If a new treatment is unlikely to outperform std of care
✅If a new treatment is similar to existing treatments, but may have un-tested benefits
5/ Thanks to our awesome team! Shoutout to the author of this byte Dr. Robert Wharton and graphics by @ivannatang
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What would you tell this patient who inquires about lab cancer #screening test to help him “live longer”?
What types of bias can occur in determining whether a cancer screening test reduces mortality?
2/ Take a look at the bolded arrows below that illustrate that early detection doesn’t always mean better outcomes!
Length-time bias applies to slow-growing disease in which patients have a long phase without symptoms.
3/ Lead time bias applies to situations where patients are screened earlier, so they are diagnosed earlier, so they appear to live longer solely by nature of knowing they have the disease for a longer period of time.
We wanted to use this opportunity to shed light on the discussion on post-menopausal hormone therapy (HT) via highlighting the important yet controversial WHI trial
2/ WHI followed the Nurses' Health Study, a prospective investigation that showed HT was associated with decreased cardiovascular disease (CVD) risk
3/ WHI, a randomized controlled trial (RCT), was believed to mitigate the effects of confounding factors better than cohort studies. WHI, in contrast to the Nurses’ Health Study, showed that HT was associated with a slightly increased risk for CVD among other conditions
Let’s jump in– can you decipher the EKG below to find out what’s wrong with this patient’s His-Purkinje system?
2/ If you thought left anterior fascicular block (LAFB), you were right!
What is the formal criteria for LAFB?!
✅Left axis deviation w/o LVH
✅qR pattern in lead aVL
✅R-peak time in lead aVL of 45 ms or more
✅QRS duration less than 120 ms
3/ Why do our patients get LAFB?!
Think fibrosis in the left anterior fascicle! This causes a slowed electrical conduction → EKG findings.