Rolf Foruli, Scandinavian academic and Watchtower apologist, has come out with a video at times quoting figures on mental disease from the 1930's and 40's, in support of his allegation that the rate of mental problems and depression is actually only a third of what it is among the entire population.
There are numerous holes in his presentation. For one, when JW's are DA'ed or DF'ed they're no longer considered JW's and only active JW's are part of the results. Those who were victimized and suffered the most mental trauma as JW's aren't even considered in the studies he mentions.
Watch his video: "The Mental Health of Jehovah´s Witnesses" R. Furuli, on YouTube:
The real question might be "what is Rolf Foruli's own state of mental health?"