Table 2.
Internal consistency, descriptive statistics, and sex differences of the MIA scales and subscales
| N items | Alpha | Total sample | Males | Females | Effect size | |
|---|---|---|---|---|---|---|
| N = 1443 | N = 691 | N = 753 | ||||
| M (SD) | M (SD) | M (SD) | ||||
| Psychopathology scales | ||||||
| Social Phobia | 8 | 0.90 | 2.40 (2.18) | 1.85 (1.91) | 2.91 (2.28) | 0.50*** |
| ADHD | 16 | 0.89 | 2.94 (1.67) | 2.84 (1.69) | 3.03 (1.65) | 0.11* |
| Impulsivity | 6 | 0.84 | 2.78 (1.96) | 2.71 (2.03) | 2.85 (1.89) | 0.07 |
| Hyperactivity | 4 | 0.70 | 2.61 (2.13) | 2.60 (2.14) | 2.62 (2.13) | 0.01 |
| Inattention | 6 | 0.77 | 3.31 (1.97) | 3.13 (1.91) | 3.48 (2.01) | 0.18** |
| Generalized Anxiety | 9 | 0.86 | 4.10 (2.17) | 3.27 (1.97) | 4.86 (2.08) | 0.78*** |
| Eating Disorders | 5 | 0.70 | 1.60 (1.66) | 1.13 (1.35) | 2.04 (1.79) | 0.57*** |
| Conduct Disorder | 16 | 0.95 | 0.65 (0.90) | 0.63 (0.90) | 0.66 (0.91) | 0.02 |
| Lying | 5 | 0.84 | 0.99 (1.27) | 0.97 (1.25) | 1.01 (1.28) | 0.04 |
| Stealing | 5 | 0.90 | 0.22 (0.73) | 0.24 (0.80) | 0.21 (0.66) | –0.05 |
| Rule Breaking | 4 | 0.85 | 0.92 (1.54) | 0.81 (1.41) | 1.01 (1.65) | 0.13* |
| Vandalism | 2 | 0.87 | 0.29 (1.02) | 0.43 (1.18) | 0.17 (0.83) | −0.26*** |
| Depression | 8 | 0.90 | 3.48 (2.25) | 2.63 (1.95) | 4.26 (2.22) | 0.78*** |
| Self‐harm | 3 | 0.72 | 0.37 (1.19) | 0.16 (0.71) | 0.56 (1.47) | 0.34*** |
| Delinquency & Contact with Police | 5 | 0.91 | 0.22 (0.73) | 0.31 (0.86) | 0.14 (0.57) | −0.23*** |
| Oppositional Defiant Disorder | 9 | 0.84 | 2.35 (1.39) | 2.35 (1.36) | 2.35 (1.41) | 0.00 |
| Psychopathy | 4 | 0.46 | 3.35 (1.73) | 3.73 (1.83) | 3.00 (1.55) | −0.43*** |
| Aggression | 18 | 0.96 | 0.74 (0.88) | 0.84 (0.95) | 0.65 (0.79) | −0.22*** |
| Severe Physical Violence | 5 | 0.92 | 0.26 (0.86) | 0.37 (1.05) | 0.16 (0.61) | −0.26*** |
| Proactive Aggression | 4 | 0.91 | 0.18 (0.72) | 0.22 (0.77) | 0.13 (0.67) | −0.12* |
| Reactive Aggression | 3 | 0.84 | 0.66 (1.42) | 0.97 (1.66) | 0.37 (1.09) | −0.44*** |
| Social Aggression | 6 | 0.86 | 1.57 (1.42) | 1.59 (1.43) | 1.56 (1.41) | −0.02 |
| Total of Internalizing Symptoms | 28 | 0.94 | 3.04 (1.74) | 2.35 (1.49) | 3.67 (1.71) | 0.82*** |
| Total of Externalizing Symptoms | 56 | 0.97 | 1.44 (0.93) | 1.45 (0.96) | 1.44 (0.90) | −0.01 |
| Functional impairment scales | ||||||
| Anxiety | 4 | 0.88 | 1.85 (2.21) | 1.34 (1.85) | 2.32 (2.40) | 0.45*** |
| Behaviour | 4 | 0.93 | 0.64 (1.44) | 0.68 (1.40) | 0.62 (1.47) | −0.04 |
| Eating disorders | 4 | 0.94 | 0.59 (1.47) | 0.31 (0.94) | 0.86 (1.78) | 0.38*** |
| Depression | 4 | 0.90 | 1.92 (2.27) | 1.23 (1.86) | 2.54 (2.43) | 0.60*** |
| Total functional impairment | 16 | 0.94 | 1.25 (1.46) | 0.89 (1.15) | 1.58 (1.62) | 0.49*** |
Note: The table reports the descriptive statistics for all the MIA scales, subscales, and dimensions. All scores were rescaled to be expressed on a scale from 0 to 10. ADHD, Attention Deficit Hyperactivity Disorder; M, mean; SD, standard deviation. Effect size based on Hedge's g; p values are based on t‐tests.
*
p < 0.05.
**
p < 0.01.
***
p < 0.001.