The Movie Provoking the Most Fearful Responses

From today's New York Times comes this obituary of Dr. Peter B. Neubauer, a child psychologist who focused on violence on television. At the end it says:

In 1982, Dr. Neubauer turned to studying the effects of horror films and likened their gory images to television’s. He concluded that children with a healthy home life could usually see the difference between fantastic images and reality. But he also found that children from emotionally turbulent families sometimes made links between frightening images and their relationships at home.

Fair enough. And what "horror film" did Neubauer find to be the most effective?

Dr. Neubauer found that the film “The Wizard of Oz” provoked the most fearful responses. The film seductively mixed realism with fantasy, he said, and presented the actress playing the dream character of the witch in another role, that of a neighbor, which deeply troubled many child viewers.

Which I think was the moviemakers' point. They created a frightening villain for their young protagonist to overcome.

Neubauer could also find some value in the MGM The Wizard of Oz, citing the Wizard's remarks about courage on one page in Nature's Thumbprint, written with his son Alexander Neubauer.