It is pretty bad, but people have seriously argued that the evacuation itself killed more people: Japan (like any other highly populated First World country!) is stuffed full of old or sick people, and when you force them to evacuate quickly and be separated from all their stuff, their doctors and medical records, their local pharmacies, and subject them to a ton of stress in every respect - well, quite a few people are going to kick the bucket.
I think the evidence on that point is incontrovertible. On the other hand it would have been politically impossible to refuse to evacuate people in the area.
