Table 2.
Variation in fluid intelligence* as a function of psychiatric disorders in a population representation sample of adolescents (N=10,073)
| Past 12 month disorders, all ages | Lifetime, but not 12 months disorders, all ages | |||||||
|---|---|---|---|---|---|---|---|---|
| Mean IQ | SE | Beta | p value+ | Mean IQ | SE | Beta | p value+ | |
| I. Fear disorders | ||||||||
| Specific phobia | 97.1 | 0.39 | −1.31 | 0.001 | 99.1 | 0.76 | −0.11 | 0.89 |
| Agoraphobia | 98.8 | 0.98 | −0.45 | 0.65 | 98.2 | 1.66 | −1.12 | 0.50 |
| Social phobia | 98.6 | 0.43 | −0.51 | 0.25 | 97.4 | 1.17 | −1.67 | 0.15 |
| Panic disorder | 98.4 | 1.04 | −0.90 | 0.39 | 97 | 2.1 | −2.34 | 0.27 |
| No fear disorder | 99.1 | 0.22 | -- | -- | 99.1 | 0.22 | -- | -- |
| II. Distress disorders | ||||||||
| Separation anxiety disorder | 96.8 | 1.13 | −1.89 | 0.10 | 97.2 | 0.61 | −1.56 | 0.01 |
| Post-traumatic stress disorder** | 99.7 | 0.88 | 0.94 | 0.29 | 96.8 | 1.46 | −1.92 | 0.19 |
| Major depressive episode/dysthymia | 100 | 0.5 | 1.32 | 0.01 | 99.7 | 0.72 | 1.07 | 0.14 |
| Generalized anxiety disorder | 97.6 | 1.11 | −1.12 | 0.32 | 96.7 | 1.3 | −2.05 | 0.12 |
| No distress disorder | 98.8 | 0.25 | -- | -- | 98.8 | 0.25 | -- | -- |
| III. Behavior disorders | ||||||||
| ADHD | 96.3 | 0.91 | −2.91 | 0.002 | 97.2 | 1.05 | −2.02 | 0.05 |
| Oppositional defiant disorder | 97.3 | 0.66 | −1.81 | 0.007 | 98.6 | 0.62 | −0.5 | 0.42 |
| Conduct disorder | 97.1 | 0.82 | −1.94 | 0.02 | 97.6 | 0.91 | −1.44 | 0.12 |
| Eating disorders | 97.9 | 0.82 | −1.28 | 0.12 | 98.4 | 0.91 | −0.81 | 0.374 |
| No behavior disorder | 99.1 | 0.21 | -- | -- | 99.1 | 0.21 | -- | -- |
| IV. Substance disorders | ||||||||
| Alcohol abuse | 96.5 | 0.67 | −2.6 | <.001 | 97.6 | 1.1 | −1.49 | 0.18 |
| Drug abuse | 97.6 | 0.64 | −1.44 | 0.02 | 97.9 | 0.81 | −1.18 | 0.14 |
| No substance disorder | 99.1 | 0.21 | -- | -- | 99.1 | 0.21 | -- | -- |
| V. Other disorders | ||||||||
| Bipolar disorder | 94.2 | 1.69 | −4.97 | 0.004 | 98.3 | 3.05 | −0.9 | 0.77 |
| No bipolar disorder | 99.2 | 0.21 | -- | -- | 99.2 | 0.21 | -- | -- |
| VI. Total number of disorders | ||||||||
| Exactly one disorder | 98.2 | 0.42 | −0.99 | 0.02 | 99.7 | 0.51 | 0.88 | 0.09 |
| Exactly two disorders | 98.2 | 0.54 | −0.97 | 0.08 | 97.5 | 1.08 | −1.25 | 0.24 |
| Three or more disorders | 97.8 | 0.43 | −1.36 | 0.002 | 95.9 | 1.76 | −2.93 | 0.10 |
| No disorder | 98.8 | 0.21 | -- | -- | 98.8 | 0.21 | -- | -- |
Scores were first normed in the sample by six-month age groups for mean of 100 and standard deviation of 15. Predicted means were estimated from linear regression models controlling for parental education; race/ethnicity, age, nativity (US born versus not), number of siblings, birth order, and non-focal disorder groups.
Among those with a lifetime exposure to a potentially traumatic event (N=6160, 61.2% of the total sample).
P-values are for the comparison between each disorder category to a reference group of no disorder in that category. For example, mean IQ among those with specific phobia is compared to those with no fear disorder. All p-values are false discovery rate adjusted.