Though this study seemed to be a global survey of hospital visits and treatment relating to each substance, rather than each substances pharmacological profile.
The Global Drug Survey, an independent research company that, since 2014, has partnered with medical experts and media groups to conduct its annual survey, compiled responses from more than 115,000 people in over 50 countries for its 2017 edition. More than 10,000 people from the U.S. responded
http://www.huffingtonpost.com/entry/glo ... d8f81ec08f
Additional article on the topic from popular science:
If you’re looking to play it safe when it comes to illicit substances, look no further than the humble shroom. It’s non-addictive, hard to overdose on, and you can grow it yourself. And, according to a massive report by the Global Drug Survey, it sends the fewest people to the emergency room of any drug on the market.
Of coarse, this is old news, psychedelics are safe, however I'm not sure that a comparison of hospital visits is the proper method to determine the safety of a substance, it is good information, but modern pharmacology could have told us this a long time ago.
Below David E. Nichols comments on LSD:
The primary health concerns about LSD use are related to psychological health rather than risk of physical damage to the body or brain. As senior LSD researcher Dr. David Nichols, Distinguished Chair of Pharmacology at Purdue University and head of one of the world's top LSD research labs, stated in his 2004 review article on hallucinogens, "There is no evidence that any of the hallucinogens, even the very powerful semisynthetic LSD, causes damage to any human body organ. [...] Hallucinogens do not cause life-threatening changes in cardiovascular, renal, or hepatic function because they have little or no affinity for the biological receptors and targets that mediate vital vegetative functions." Deaths resulting from the pharmacological effects of LSD are rare to non-existent
However, I am glad that culture is finally comming to terms with the truth about these compounds, which was my main reason for sharing these articles, it's a good sign that the mass perception of these compounds is changing for the better.