I didn't say that all positive evidence is low quality, and I definitely didn't say that all negative evidence is high quality.
My logic works like this:
1. Cannabis has a number of plausibly pharmacologically active chemicals.
2. The effects these pharmacologically active chemicals have may help some things, and make other things worse. Both are almost certainly true, depending on which things we are talking about.
3. Many of the sources of information on this topic are biased, either by the anti-drug movement, which cannot abide any positive findings, and the pro-drug movement driven both by the counter-culture and more recently commercial interests.
4. In the face of both of these biases, US federal regulations has made study of therapeutic use next to impossible. Studies of those using voluntarily in the community, however, is still possible.
5. Of the studies that have been done, most focus on the negative impacts. Not all of these studies are good, but many of them are. In fact, a good number of them are excellent. I'm not saying it's a fair fight, but that is the state of the science in 2015.
6. Perhaps, in time, as the playing field is leveled and good randomized controlled trials with strong blinding can be conducted, high-quality evidence for cannabis as a legitimate therapy can happen. That has not yet happened.
7. Despite the absence of evidence, many people are making lots of money off of cannabis, and have a strong incentive to promote this message regardless of the evidence (or lack thereof).
8. As the benefits are mostly unknown, and the risks are quite well known (based on lots of poor research but also quite a bit of high quality research), I cannot recommend medical marijuana at this time.
9. This is a moving target. I will need to continue to follow research trends, and my recommendations will change based on available data.
I hope that is more explicit.
Also, I know it's ad hominem, but I would be remiss not to point out that linking to reddit and wikipedia is not nearly as strong as pointing to well-conducted primary literature sources. Also, take a look at the reddit link you posted. The ratio of negative outcomes of use to positive is very high.
I appreciate that you have clarified your reasoning, and I certainly don't intend to insult, but I really feel there is some amount of cognitive dissonance going on here. For example, from your original comment and new comment:
> but no amount of enthusiasm changes the fact that high-quality research hasn't happened yet.
> I didn't say that all positive evidence is low quality
You are now conceding that there is high-quality research, but have since made more claims which are completely dismissive of that evidence. So, while I wouldn't argue with most of the points you just made, I still feel that your basis for dismissing positive research is flawed, at best.
The purpose of linking to Reddit was to provide an encompassing list of the published papers. It isn't a list of comments from random people on the internet, it's a list of scientific journals and websites which you, yourself, would recognize as being respectable sources. Likewise, the purpose of linking to Wikipedia entries was to give an overview or example. You are more than welcome to scroll to the bottom of the page and look at the actual sources for that information. It is unreasonable to insist that someone provide hundreds of sources at the bottom of a comment, when they are already consolidated elsewhere.
As to your point about negative results being more likely or common than positive ones, I don't see how that has anything to do with the topic at hand, which is that you seem to be convinced that positive claims are either flawed or tainted to the point of being illegitimate. Even if 99 out of 100 research efforts resulted in negative outcomes, that is not a reason to dismiss the one. Just as it is not a reason to dismiss positive research based on some (or even a majority) of it being supported or influenced by third parties.
You are right to point this out as contradictory, and I'm happy to clarify. It's more a product of trying to reply quickly.
Often in medical research, we see early high-quality studies purporting an effect. As a recent example, fish oil for hyperlipidemia. Positive studies (meaning ones that show an effect beyond placebo) are more likely to get picked up for publication, and ones that show new/interesting findings even more so. But the general trend, for nearly everything, is that continued research shows less effectiveness than the original studies. All too commonly, the effect with more and better studies becomes nearly indistinguishable from placebo. The media is very fond of pointing out this apparent "fip-flopping" as evidence that scientists are idiots.
That's where we are now with marijuana research. A handful of high-quality studies is a compelling start for more research, but not a basis for a robust conclusion, especially in the face of the large body of evidence for harm. Fish oil does not have that degree of harm, for example, so the early studies of effectiveness could meet a threshold of risk/benefit much more easily.
Hope that helps.
The reddit link does indeed have a bunch of peer-reviewed studies, but they are of highly variable quality. Not all articles, regardless of journal, are great. The negative outweighing the positive was related to my observation of the bias of cannabis research, and as you rightly point out that does not preclude a well-conducted body of research on a specific indication (for example, pain) from demonstrating an effect beyond placebo.
My logic works like this:
1. Cannabis has a number of plausibly pharmacologically active chemicals.
2. The effects these pharmacologically active chemicals have may help some things, and make other things worse. Both are almost certainly true, depending on which things we are talking about.
3. Many of the sources of information on this topic are biased, either by the anti-drug movement, which cannot abide any positive findings, and the pro-drug movement driven both by the counter-culture and more recently commercial interests.
4. In the face of both of these biases, US federal regulations has made study of therapeutic use next to impossible. Studies of those using voluntarily in the community, however, is still possible.
5. Of the studies that have been done, most focus on the negative impacts. Not all of these studies are good, but many of them are. In fact, a good number of them are excellent. I'm not saying it's a fair fight, but that is the state of the science in 2015.
6. Perhaps, in time, as the playing field is leveled and good randomized controlled trials with strong blinding can be conducted, high-quality evidence for cannabis as a legitimate therapy can happen. That has not yet happened.
7. Despite the absence of evidence, many people are making lots of money off of cannabis, and have a strong incentive to promote this message regardless of the evidence (or lack thereof).
8. As the benefits are mostly unknown, and the risks are quite well known (based on lots of poor research but also quite a bit of high quality research), I cannot recommend medical marijuana at this time.
9. This is a moving target. I will need to continue to follow research trends, and my recommendations will change based on available data.
I hope that is more explicit.
Also, I know it's ad hominem, but I would be remiss not to point out that linking to reddit and wikipedia is not nearly as strong as pointing to well-conducted primary literature sources. Also, take a look at the reddit link you posted. The ratio of negative outcomes of use to positive is very high.