Оригинал
I've heard about 1 in 100. That wouldn't be all extreme cases though. People with severe trich who pull from their scalp would have to resort to covering their natural hair - or lack of, with wigs or scarves or shaving, because there just isn't hair left on the scalp for covering the loss up. The same with those with severe eyelash or brow trich - the loss would be obvious.