Table 2.
Age at onset by onset definition and by sex for mental disorders (ICD-11 blocks highlighted in italics).
| Disorder | Onset definition/sex | Samples | Peak age at onset (years) | Proportion onset by 14 years | Proportion onset by 18 years | Proportion onset by 25 years | p25 | Median | p75 |
|---|---|---|---|---|---|---|---|---|---|
| Any mental disorder | First symptoms | 5 | 4.5 | 41.5% | 50.0% | 69.5% | 8 | 18 | 27 |
| Any mental disorder | First diagnosis | 6 | 5.5 | 38.6% | 54.1% | 68.3% | 9 | 16 | 33 |
| Neurodevelopmental disorders | First symptoms | 8 | 5.5 | 40.4% | 56.0% | 62.9% | 7 | 16 | – |
| Neurodevelopmental disorders | First diagnosis | 11 | 5.5 | 61.3% | 82.6% | 95.0% | 7 | 12 | 16 |
| Neurodevelopmental disorders | Female | 5 | 9.5 | 59.6% | 74.5% | 82.2% | 7 | 12 | 18 |
| Neurodevelopmental disorders | Male | 4 | 9.5 | 67.0% | 81.2% | 89.0% | 7 | 11 | 15 |
| Autism spectrum disorder | First diagnosis | 2 | 5.5 | 72.4% | 89.8% | 94.8% | 5 | 9 | 14 |
| Autism spectrum disorder | Female | 2 | 5.5 | 80.1% | 92.3% | 96.0% | 5 | 8 | 12 |
| Autism spectrum disorder | Male | 2 | 5.5 | 80.6% | 92.4% | 96.0% | 5 | 8 | 12 |
| Attention deficit hyperactivity disorder | First symptoms | 2 | 4.5 | 99.8% | 99.8% | 100.0% | 4 | 5 | 7 |
| Attention deficit hyperactivity disorder | First diagnosis | 9 | 9.5 | 56.2% | 72.5% | 91.8% | 8 | 12 | 18 |
| Attention deficit hyperactivity disorder | Female | 3 | 9.5 | 65.0% | 81.0% | 95.2% | 8 | 11 | 16 |
| Attention deficit hyperactivity disorder | Male | 3 | 9.5 | 67.5% | 81.3% | 94.9% | 8 | 11 | 15 |
| Anxiety and fear-related disorders | First symptoms | 31 | 4.5 | 45.1% | 59.9% | 71.9% | 5 | 15 | 27 |
| Anxiety and fear-related disorders | First diagnosis | 18 | 5.5 | 35.5% | 48.5% | 71.0% | 9 | 18 | 26 |
| Anxiety and fear-related disorders | Female | 6 | 19.5 | 11.6% | 22.9% | 45.8% | 18 | 26 | 40 |
| Anxiety and fear-related disorders | Male | 7 | 19.5 | 21.8% | 31.4% | 52.4% | 15 | 24 | 37 |
| Specific phobia/separation anxiety disorder | First symptoms | 12 | 4.5 | 71.2% | 77.6% | 82.8% | 5 | 7 | 16 |
| Specific phobia/separation anxiety disorder | First diagnosis | 9 | 5.5 | 72.1% | 76.0% | 85.0% | 6 | 9 | 16 |
| Specific phobia/separation anxiety disorder | Female | 2 | 4.5 | 58.3% | 60.6% | 68.2% | 5 | 8 | 30 |
| Specific phobia/separation anxiety disorder | Male | 2 | 5.5 | 50.0% | 53.6% | 70.2% | 7 | 13 | 26 |
| Social anxiety disorder | First symptoms | 9 | 14.5 | 54.6% | 75.4% | 81.5% | 7 | 13 | 17 |
| Social anxiety disorder | First diagnosis | 7 | 14.5 | 47.5% | 77.1% | 85.4% | 10 | 14 | 17 |
| Panic disorder | First symptoms | 10 | 15.5 | 11.9% | 28.9% | 56.4% | 17 | 22 | 32 |
| Panic disorder | First diagnosis | 10 | 39.5 | 9.3% | 20.7% | 43.8% | 19 | 27 | 40 |
| Panic disorder | Female | 3 | 20.5 | 20.8% | 29.0% | 53.4% | 16 | 24 | 31 |
| Panic disorder | Male | 3 | 15.5 | 16.1% | 32.9% | 56.9% | 16 | 22 | 31 |
| Generalised anxiety disorder | First symptoms | 13 | 15.5 | 9.4% | 21.3% | 32.8% | 19 | 39 | 52 |
| Generalised anxiety disorder | First diagnosis | 8 | 45.5 | 7.5% | 15.2% | 27.3% | 23 | 34 | 48 |
| Obsessive-compulsive related disorder | First symptoms | 6 | 14.5 | 23.4% | 48.1% | 71.6% | 14 | 18 | 25 |
| Obsessive-compulsive related disorder | First diagnosis | 11 | 14.5 | 24.1% | 44.1% | 56.4% | 14 | 20 | 35 |
| Obsessive-compulsive related disorder | Female | 4 | 15.5 | 16.9% | 32.8% | 55.5% | 16 | 23 | 30 |
| Obsessive-compulsive related disorder | Male | 4 | 10.5 | 27.7% | 42.6% | 67.1% | 13 | 20 | 27 |
| Feeding or eating disorders | First symptoms | 4 | 15.5 | 10.2% | 40.1% | 77.2% | 16 | 19 | 24 |
| Feeding or eating disorders | First diagnosis | 7 | 15.5 | 16.0% | 44.7% | 74.2% | 15 | 18 | 25 |
| Feeding or eating disorders | Female | 4 | 14.5 | 23.0% | 54.8% | 76.5% | 14 | 17 | 23 |
| Feeding or eating disorders | Male | 4 | 14.5 | 37.6% | 67.3% | 86.9% | 12 | 15 | 19 |
| Anorexia nervosa | First symptoms | 3 | 15.5 | 20.4% | 59.9% | 89.0% | 14 | 16 | 20 |
| Anorexia nervosa | First diagnosis | 5 | 15.5 | 10.6% | 37.3% | 54.6% | 16 | 22 | 87 |
| Binge eating disorder | First symptoms | 2 | 19.5 | 15.5% | 31.4% | 70.4% | 16 | 20 | 28 |
| Binge eating disorder | First diagnosis | 3 | 15.5 | 8.2% | 34.5% | 73.5% | 16 | 20 | 25 |
| Trauma-related disorders | First symptoms | 6 | 25.5 | 13.3% | 23.4% | 33.0% | 18 | 33 | 48 |
| Trauma-related disorders | First diagnosis | 7 | 15.5 | 19.4% | 31.3% | 46.1% | 15 | 29 | 46 |
| Disorders due to substance use or addictive behaviours | First symptoms | 34 | 15.5 | 8.2% | 39.1% | 78.4% | 16 | 19 | 23 |
| Disorders due to substance use or addictive behaviours | First diagnosis | 21 | 20.5 | 1.6% | 9.5% | 41.3% | 21 | 28 | 43 |
| Disorders due to substance use or addictive behaviours | Female | 11 | 20.5 | 0.8% | 5.7% | 34.3% | 22 | 31 | 45 |
| Disorders due to substance use or addictive behaviours | Male | 12 | 20.5 | 2.5% | 13.2% | 41.8% | 20 | 27 | 41 |
| Disorder due to use of cannabis | First symptoms | 2 | 20.5 | 5.8% | 8.5% | 17.2% | 30 | 44 | 63 |
| Disorder due to use of cannabis | First diagnosis | 5 | 20.5 | 3.0% | 16.7% | 66.0% | 19 | 22 | 27 |
| Disorder due to use of cannabis | Female | 3 | 20.5 | 4.0% | 15.9% | 61.3% | 19 | 23 | 28 |
| Disorder due to use of cannabis | Male | 3 | 20.5 | 3.3% | 14.6% | 61.5% | 19 | 23 | 28 |
| Disorder due to use of alcohol | First symptoms | 25 | 15.5 | 8.4% | 39.2% | 71.9% | 16 | 19 | 26 |
| Disorder due to use of alcohol | First diagnosis | 15 | 20.5 | 0.9% | 4.5% | 27.1% | 24 | 36 | 47 |
| Disorder due to use of alcohol | Female | 9 | 44.5 | 0.1% | 1.5% | 16.2% | 29 | 40 | 50 |
| Disorder due to use of alcohol | Male | 9 | 15.5 | 2.9% | 13.8% | 29.0% | 22 | 36 | 47 |
| Schizophrenia-spectrum and primary psychotic disorders | First symptoms | 11 | 24.5 | 6.0% | 15.0% | 51.1% | 20 | 24 | 29 |
| Schizophrenia-spectrum and primary psychotic disorders | First diagnosis | 10 | 20.5 | 2.1% | 11.2% | 45.3% | 20 | 26 | 39 |
| Schizophrenia-spectrum and primary psychotic disorders | First hospitalisation | 14 | 24.5 | 12.9% | 17.8% | 45.4% | 20 | 25 | 32 |
| Schizophrenia-spectrum and primary psychotic disorders | Female | 18 | 20.5 | 2.4% | 10.0% | 45.4% | 21 | 26 | 35 |
| Schizophrenia-spectrum and primary psychotic disorders | Male | 18 | 20.5 | 7.6% | 15.9% | 49.9% | 20 | 25 | 32 |
| Schizophrenia | First symptoms | 8 | 24.5 | 7.2% | 18.0% | 54.8% | 19 | 24 | 28 |
| Schizophrenia | First diagnosis | 8 | 20.5 | 0.9% | 6.5% | 43.7% | 21 | 26 | 39 |
| Schizophrenia | First hospitalisation | 10 | 25.5 | 30.2% | 34.5% | 52.0% | 11 | 24 | 31 |
| Schizophrenia | Female | 16 | 20.5 | 2.5% | 8.3% | 45.7% | 21 | 25 | 33 |
| Schizophrenia | Male | 16 | 20.5 | 6.0% | 11.6% | 48.7% | 20 | 25 | 31 |
| Acute and transient psychotic disorder | First diagnosis | 2 | 19.5 | 1.8% | 6.6% | 20.6% | 27 | 35 | 45 |
| Personality disorders | First symptoms | 2 | 5.5 | 93.6% | 96.3% | 96.5% | 5 | 7 | 10 |
| Personality disorders | First diagnosis | 4 | 20.5 | 2.2% | 10.0% | 49.2% | 20 | 25 | 32 |
| Personality disorders | Female | 3 | 20.5 | 0.8% | 5.5% | 37.7% | 22 | 27 | 37 |
| Personality disorders | Male | 3 | 20.5 | 14.4% | 19.6% | 47.7% | 19 | 25 | 34 |
| Mood disorders | First symptoms | 32 | 19.5 | 12.2% | 26.1% | 51.7% | 17 | 24 | 36 |
| Mood disorders | First diagnosis | 40 | 20.5 | 2.2% | 10.7% | 33.3% | 22 | 32 | 48 |
| Mood disorders | Female | 22 | 20.5 | 1.0% | 5.4% | 22.0% | 26 | 40 | 56 |
| Mood disorders | Male | 22 | 20.5 | 3.4% | 9.0% | 24.9% | 25 | 38 | 55 |
| Depressive disorder | First symptoms | 22 | 15.5 | 10.2% | 25.9% | 47.0% | 17 | 26 | 34 |
| Depressive disorder | First diagnosis | 35 | 19.5 | 2.5% | 12.0% | 35.8% | 21 | 31 | 46 |
| Depressive disorder | Female | 18 | 20.5 | 1.1% | 5.9% | 22.4% | 26 | 40 | 55 |
| Depressive disorder | Male | 17 | 20.5 | 3.5% | 9.0% | 24.5% | 25 | 38 | 54 |
| A bipolar or related disorder | First symptoms | 15 | 19.5 | 10.3% | 30.9% | 68.8% | 16 | 21 | 26 |
| A bipolar or related disorder | First diagnosis | 24 | 20.5 | 0.6% | 2.7% | 18.8% | 28 | 40 | 52 |
| A bipolar or related disorder | Female | 8 | 19.5 | 1.7% | 7.8% | 23.3% | 26 | 39 | 52 |
| A bipolar or related disorder | Male | 7 | 49.5 | 4.4% | 12.2% | 24.5% | 25 | 39 | 52 |
p25, p75, 25th and 75th percentile. Only the earliest peaks are shown. Curves were calculated when at least two studies were included for each ICD-11 block or disorder. Bootstrap comparisons were run when at least five studies were included for each disorder; no significant difference emerged by sex or onset definition.