Rates of depression and anxiety among young people in America have been increasing steadily for the past 50 to 70 years. Today, by at least some estimates, five to eight times as many high school and college students meet the criteria for diagnosis of major depression and/or anxiety disorder as was true half a century or more ago. This increased psychopathology is not the result of changed diagnostic criteria; it holds even when the measures and criteria are constant.
The most recent evidence for the sharp generational rise in young people’s depression, anxiety, and other mental disorders comes from a just-released study headed by Jean Twenge at San Diego State University. Twenge and her colleagues took advantage of the fact that the Minnesota Multiphasic Personality Inventory (MMPI), a questionnaire used to assess a variety of mental disorders, has been given to large samples of college students throughout the United States going as far back as 1938, and the MMPI-A (the version used with younger adolescents) has been given to samples of high school students going as far back as 1951. The results are consistent with other studies, using a variety of indices, which also point to dramatic increases in anxiety and depression—in children as well as adolescents and young adults—over the last five or more decades
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