An article appearing in the Los Angeles Times discussed a report from the New England Journal of Medicine. The article, titled "Crosswords Reduce Risk of Dementia," stated that "Elderly people who frequently read, do crossword puzzles, practice a musical instrument or play board games cut their risk of Alzheimer's and other forms of dementia by nearly two-thirds compared with people who seldom do such activities. . . ." Comment on the statement in quotes, keeping in mind the type of study for which causation can be reasonably inferred.