Thirdly, a further, broader clinical implication of these results is that it demonstrates that age 18 as an intake threshold for adult mental health services is artificial and not based on global epidemiological evidence (nor on biological evidence of age when major brain changes occur [41]). To the best of our knowledge, mental health specialist training and mental health services in most parts of the world, including North America, Australia, most European countries, including Italy, Germany, UK, are divided between child/adolescent psychiatry and adult psychiatry. Given that the vast majority of mental disorders diagnoses seen in adulthood show a peak of onset before age 18, such a bifurcated mental health system is not evidence-based and may disadvantage individuals with developmental disorders from accessing and receiving adequate and continuous care [62]. Moreover, most psychiatry training programmes fail to target the transition period from childhood and adolescence to adult psychiatry [63]. Although many mental health services have tried to address this discontinuity of care [63, 64], significant gaps remain. Future mental health reforms could leverage and refine clinical high-risk services for young
