Electroconvulsive therapy is about as effective as bloodletting. There are conditions for which bloodletting is an effective treatment, such as iron overload. But in most people, and under most circumstances, losing meaningful quantities of blood leads to long-term injury and/or death. Likewise, electrocuting the nervous system often causes permanent disability and/or death, and is a fairly effective torture method.

Lobotomy, too, can be an effective treatment for epilepsy. But I'm sure we can all agree that certain people in the past were way too quick to resort to it. (The Soviet Union banned it in the 1950s, on human rights grounds.) Likewise, I'm rather worried by the high incidence of involuntary (read: forced, non-consensual) electroconvulsive therapy. 10% is way too high, and I've seen numbers higher than that…