Table 1 Descriptives and mean group differences in the Youth Psychopathic traits Inventory (YPI) and the Antisocial Process Screening Device-self-report (APSD-SR) scores between 15- to 16-year-old boys (n = 174) and girls (n = 198) attending the 9th grade at 5 secondary schools in Finland. Comparisons are performed using the Mann–Whitney U-test. Effect sizes (Cohen’s d) are reported
| Â | Boys | Girls | Statistics | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|  | Mean (SD) | Minimum-maximum | Median | Skewness (SE = 0.184) | Kurtosis (SE = 0.366) | Mean (SD) | Minimum-maximum | Median | Skewness (SE = 0.173) | Kurtosis (SE = 0.344) | Mann–Whitney U Test | Cohen’s d |
YPI Sub-dimension | ||||||||||||
Dishonest charm | 1.80 (0.68) | 1.00-4.00 | 1.80 | 0.839 | 0.579 | 1.73 (0.66) | 1.00-4.00 | 1.60 | 0.860 | 0.309 | 16083.50 | 0.104 |
Grandiosity | 1.89 (0.68) | 1.00-4.00 | 1.80 | 1.040 | 1.103 | 1.58 (0.61) | 1.00-3.60 | 1.40 | 1.079 | 0.529 | 12092.50* | 0.480 |
Lying | 1.80 (0.67) | 1.00-4.00 | 1.80 | 0.887 | 0.687 | 1.65 (0.61) | 1.00-4.00 | 1.50 | 0.927 | 0.381 | 14955.00** | 0.234 |
Manipulation | 1.69 (0.69) | 1.00-4.00 | 1.50 | 1.075 | 0.838 | 1.63 (0.62) | 1.00-4.00 | 1.40 | 1.058 | 0.973 | 16690.50 | 0.091 |
Remorselessness | 1.69 (0.64) | 1.00-4.00 | 1.60 | 1.256 | 1.962 | 1.44 (0.53) | 1.00-4.00 | 1.40 | 1.810 | 4.532 | 12999.50* | 0.425 |
Unemotionality | 2.13 (0.56) | 1.00-4.00 | 2.20 | 0.306 | 0.442 | 1.80 (0.53) | 1.00-4.00 | 1.80 | 1.319 | 2.733 | 10740.00* | 0.605 |
Callousness | 2.23 (0.50) | 1.00-3.40 | 2.20 | −0.292 | −0.135 | 1.67 (0.47) | 1.00-4.00 | 1.60 | 0.970 | 2.183 | 6988.00* | 1.154 |
Thrill-seeking | 2.55 (0.72) | 1.00-4.00 | 2.60 | 0.021 | −0.530 | 2.49 (0.64) | 1.00-4.00 | 2.60 | 0.006 | −0.322 | 16349.00 | 0.088 |
Impulsiveness | 2.14 (0.67) | 1.00-4.00 | 2.00 | 0.347 | −0.348 | 2.22 (0.67) | 1.00-4.00 | 2.20 | 0.242 | −0.447 | 15909.50 | −0.119 |
Irresponsibility | 1.85 (0.70) | 1.00-4.00 | 1.80 | 0.754 | −0.102 | 1.60 (0.57) | 1.00-3.80 | 1.40 | 1.114 | 1.058 | 13722.00* | 0.392 |
YPI Dimension | ||||||||||||
Interpersonal | 7.18 (2.38) | 4.00-16.00 | 7.00 | 0.998 | 1.635 | 6.59 (2.10) | 4.00-15.40 | 6.40 | 1.024 | 1.381 | 14645.00** | 0.263 |
Affective | 6.05 (1.26) | 3.00-11.40 | 6.00 | 0.768 | 1.724 | 4.92 (1.25) | 3.00-12.00 | 4.60 | 1.667 | 5.534 | 8097.50* | 0.900 |
Behavioral | 6.54 (1.84) | 3.00-12.00 | 6.35 | 0.390 | −0.287 | 6.31 (1.60) | 3.20-11.40 | 6.20 | 0.414 | −0.960 | 16166.00 | 0.133 |
YPI Total | 19.77 (4.94) | 11.80-38.80 | 19.60 | 0.876 | 1.546 | 17.82 (4.19) | 10.40-37.40 | 17.20 | 1.257 | 3.4160 | 13066.00* | 0.426 |
APSD-SR Dimension | ||||||||||||
Interpersonal | 0.44 (0.40) | 0.00-2.00 | 0.29 | 1.212 | 1.650 | 0.33 (0.32) | 0.00-2.00 | 0.29 | 1.788 | 4.992 | 11552.50* | 0.304 |
Affective | 0.73 (0.34) | 0.00-1.67 | 0.67 | 0.391 | −0.041 | 0.55 (0.28) | 0.00-1.67 | 0.50 | 1.038 | 2.083 | 14392.50* | 0.578 |
Behavioral | 0.73 (0.44) | 0.00-2.00 | 0.80 | 0.423 | −0.218 | 0.68 (0.43) | 0.00-2.00 | 0.80 | 0.566 | 0.219 | 6197.50 | 0.115 |
APSD-SR Total | 1.90 (0.82) | 0.37-4.33 | 1.77 | 0.526 | 0.022 | 1.56 (0.77) | 0.31-5.18 | 1.41 | 1.284 | 2.901 | 12658.00* | 0.427 |