3 ms·

I think people misunderstand what evidence based medicine is[0]. There are many types of evidence ranging from lab studies and expert opinion at the bottom to s

I think people misunderstand what evidence based medicine is[0]. There are many types of evidence ranging from lab studies and expert opinion at the bottom to systematic reviews/meta-analyses at the top. The point being that we should strive for RCTs when possible, and that RCTs carry more weight than expert opinion or case-control. Many (I don’t have an exact number) clinical practice guidelines are based on expert opinion or observational studies, and are completely valid/evidence-based (it’s just weak evidence). The point of EBM is not “RCT or bust” it’s really more about the hierarchy, that medicine should not practice in defiance of quality evidence and that we should strive to obtain the highest quality evidence possible. [0] https://en.wikipedia.org/wiki/Hierarchy_of_evidence https://en.wikipedia.org/wiki/Hierarchy_of_evidence

maxbond 3y ago
(Saved you a search: Randomized Controlled Trial) (Corrected)
- psychphysic 3y ago
  Randomised controlled trial. Controlled means there is a control arm that get no treatment, or treatment as usual (depending on what's needed). Ideally a Db-rct a doubly blinded randomised controlled trial.
- haldujai 3y ago
  Apologies, bad medicine habit to use ambiguous acronyms. I meant "randomized controlled trial" in this case (as the post). "Randomized clinical trial" is often used interchangeably but does not necessarily require a control group (e.g. a non-inferiority study comparing two different treatments).
psychphysic 3y ago
> Many (I don’t have an exact number) clinical practice guidelines are based on expert opinion or observational studies, and are completely valid/evidence-based (it’s just weak evidence). A big problem is that humans have a preference for action, and a dislike of waiting for information. Many flawed guidelines are based on a desire to act even in the absence of evidence of benefit. "Primum non nocere" is probably the most accepted but least respected tenant of good medical practice.
- haldujai 3y ago
  > Many flawed guidelines are based on a desire to act even in the absence of evidence of benefit. Very true, I mostly intended to illustrate that many "good" or accepted guidelines are not necessarily based on randomized controlled trials as there seems to be a misconception (based on recent trending posts) that these are the only forms of "evidence" in medicine. Some guidelines are borderline pseudoscience but pertinently guidelines are not binding. You point out the correct approach - one is entirely allowed to deviate from guidelines for good reason (i.e. no/very weak evidence, questionable benefit). That's also the beauty of the EBM, you'll find grade & strength of recommendation in any modern guideline to help interpret them. We also have quality assessment tools like QUADAS-2 and the STARD reporting guidelines to help the reader assess quality. > "Primum non nocere" is probably the most accepted but least respected tenant of good medical practice. Also agree but I think EBM addresses this a lot more than the old days of science-based medicine where we did things because "they made sense" without looking at various outcome measures that sometimes reveal missed harm. > A big problem is that humans have a preference for action, and a dislike of waiting for information. Part of this is also by necessity due to the nature of patient encounters which have a need for decision-making. Where the guideline is clearly poor (e.g. adrenal nodules, homeopathic follow-up at best) I disregard them but sometimes you have to err on the side of caution. As an example I recommend pancreatic cyst follow-up per the ACR guidelines even though my (abdominal radiologist)/institutional expert opinion is they're overkill and unnecessary based on very weak and dated observational evidence. But what's the alternative, everyone just does what they want and a patient's follow-up will be variable depending on the reporting physician?

maxbond 3y ago

(Saved you a search: Randomized Controlled Trial) (Corrected)

psychphysic 3y ago
Randomised controlled trial. Controlled means there is a control arm that get no treatment, or treatment as usual (depending on what's needed). Ideally a Db-rct a doubly blinded randomised controlled trial.
haldujai 3y ago
Apologies, bad medicine habit to use ambiguous acronyms. I meant "randomized controlled trial" in this case (as the post). "Randomized clinical trial" is often used interchangeably but does not necessarily require a control group (e.g. a non-inferiority study comparing two different treatments).

psychphysic 3y ago

> Many (I don’t have an exact number) clinical practice guidelines are based on expert opinion or observational studies, and are completely valid/evidence-based (it’s just weak evidence). A big problem is that humans have a preference for action, and a dislike of waiting for information. Many flawed guidelines are based on a desire to act even in the absence of evidence of benefit. "Primum non nocere" is probably the most accepted but least respected tenant of good medical practice.

haldujai 3y ago
> Many flawed guidelines are based on a desire to act even in the absence of evidence of benefit. Very true, I mostly intended to illustrate that many "good" or accepted guidelines are not necessarily based on randomized controlled trials as there seems to be a misconception (based on recent trending posts) that these are the only forms of "evidence" in medicine. Some guidelines are borderline pseudoscience but pertinently guidelines are not binding. You point out the correct approach - one is entirely allowed to deviate from guidelines for good reason (i.e. no/very weak evidence, questionable benefit). That's also the beauty of the EBM, you'll find grade & strength of recommendation in any modern guideline to help interpret them. We also have quality assessment tools like QUADAS-2 and the STARD reporting guidelines to help the reader assess quality. > "Primum non nocere" is probably the most accepted but least respected tenant of good medical practice. Also agree but I think EBM addresses this a lot more than the old days of science-based medicine where we did things because "they made sense" without looking at various outcome measures that sometimes reveal missed harm. > A big problem is that humans have a preference for action, and a dislike of waiting for information. Part of this is also by necessity due to the nature of patient encounters which have a need for decision-making. Where the guideline is clearly poor (e.g. adrenal nodules, homeopathic follow-up at best) I disregard them but sometimes you have to err on the side of caution. As an example I recommend pancreatic cyst follow-up per the ACR guidelines even though my (abdominal radiologist)/institutional expert opinion is they're overkill and unnecessary based on very weak and dated observational evidence. But what's the alternative, everyone just does what they want and a patient's follow-up will be variable depending on the reporting physician?