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Harvard health care policy professor Ronald C Kessler is one of the most widely cited researchers in the world of psychiatry over the last decade. He is the author of more than 700 publications and a member of both the National Academy of Medicine, and the National Academy of Sciences, and a co-director of the WHO's world mental health survey.
A scale devised by Dr Kessler is used by doctors and also in workplace health and safety assessments to determine what psychological distress a person may be experiencing.
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