By A.S.
If a doctor or scientist says “there’s a lack of evidence for this” or “there’s no evidence for this”, they are conflating two very different situations:
1) “We have studied this extensively, and we have good evidence suggesting it doesn’t work / isn’t beneficial”
2) “There have been no (good) studies done on this yet, hence we lack evidence whether this works.”
For the doctor / scientist, saying “lack of evidence” is very easy because they don’t have to think whether they’re in situation 1 or 2. Whether they’re in situation 1 or 2, saying “lack of evidence” is always a medically / scientifically accurate statement to make.
However, policymakers and media interpret a doctor or scientist saying “lack of evidence” as meaning the first thing: “this has been extensively studied and we concluded it doesn’t work.”
This way, new and genuinely good ideas get squashed. Namely: it hasn’t been studied yet => a doctor or scientist says “lack of evidence” => everyone falsely interprets that as meaning “it has been extensively studied and it doesn’t work” => the idea is seen as “disproven” rather than “non-studied”.
On top of this, scientists aren’t incentivized for studying unconventional ideas that very well might not work. They probably don’t get money or respect for doing that.
Thank you for this consciousness raising post!
The book “How to Lie with Statistics” by Darrell Huff (written in 1954) is a very revealing read.
How the results of a study is worded, alone, can make HUGE differences.
We’ve been misdirected or outright lied to about so much that I tend to automatically question many things since reading that book back in the 1970’s.
I usually understand “we lack the evidence to support that” as ‘we found that to be true and immediately proceeded to discard the evidence’.
Great point, Pastafarian and Kelly, there’s also that.
So yes, the deck is profoundly stacked:
– bad things are usually accepted based on old, hacked, statistically manipulated (as Kelly said), bad, preliminary evidence
– evidence that bad but profitable things are bad is usually discarded (as Pastafarian said). It’s sometimes literally as simple as just “fund multiple studies, quietly discard all the studies that find that your profitable bad thing is bad, only publish the good-looking studies.”
– nobody’s going to fund a study whether a profitable bad thing we’re already using is actually bad. Scientists who study that also get mocked rather than respected.
– any scientist can accurately say “there’s no evidence that [bad thing we’re using] is bad” because indeed the studies showing it was bad have been quietly discarded by the industry. The public then reads “no evidence” as “we’ve extensively and sincerely studied it and concluded that it’s not bad at all.”
– even if a scientist finds conclusive evidence that a bad thing is bad, there’s no way that a billion-dollar industry is just going to say “whoops, you’re right, guess we’ll disband ourselves now.”
– Plus if I want to publish a “profitable thing is bad” study, peer reviewers and journal editors are going to be much, MUCH more critical and nitpicky of me than they were earlier of the “that profitable thing is good” paper.