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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Which of the following disorders may be diagnosed even if the onset is after age 18 years?
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The correct answer is  Ans. D. Tic disorder not otherwise specifiedAll tic disorders with onset after age 18 years must be diagnosed as tic disorder not otherwise specified, a residual category for tics that do not meet the criteria for a specific tic disorder. Transient tic disorder, chronic motor or vocal tic disorder, and Tourette's disorder all specify onset before age 18 years.