Table 2.
Mean and percentages of study variables as DRD2 allele types.
| Variables (Range) |
DRD2 C957T Risk Allele Carriers
(n = 14) |
DRD2 C957T Nonrisk
Allele Carriers (n = 154) |
Test Statistics
Differences |
| M(SD) | M(SD) | ||
| Male | 80% | 62% | x2(1) = 1.57 |
| Age (19–33) | 22.29(2.52) | 22.07(2.35) | t(166) = 0.33 |
| Problematic gaming (1–105) | 34.21(21.47) | 40.17(23.20) | t(166) = −0.93 |
| Interpersonal stress (0–15) | 0.21(0.43) | 1.00(1.98) | t(85.86) = −4.01 *,a |
| Avoidant coping (6–22) | 11.21(4.37) | 12.47(3.66) | t(166) = −1.21 |
| Impulsivity (22–69) | 42.50(8.79) | 42.92(8.66) | t(166) = −0.17 |
| Depression (0–25) | 4.64(4.29) | 6.52(5.21) | t(166) = −1.31 |
| Anxiety (0–21) | 2.57(1.95) | 5.03(5.16) | t(33.63) = −3.69 *,a |
| ADHD (0–6) | 2.14(1.17) | 2.87(2.87) | t(18.48) = −2.13 *,a |
| Variables (Range) |
DRD2 Taq1 Risk Allele Carriers (n = 119) |
DRD2 Taq1 Nonrisk
Allele Carriers (n = 49) |
Test Statistics
Differences |
| M(SD) | M(SD) | ||
| Male | 80% | 62% | x2(1) = 0.10 |
| Age (19–33) | 22.03(2.41) | 22.22(2.23) | t(166) = −0.48 |
| Problematic gaming (1–105) | 39.39(23.30) | 40.37(22.66) | t(166) = −0.25 |
| Interpersonal stress (0–15) | 0.96(2.00) | 0.88(1.68) | t(166) = 0.25 |
| Avoidant coping (6–22) | 12.49(3.89) | 12.08(3.32) | t(166) = 0.64 |
| Impulsivity (22–69) | 42.66(9.03) | 43.43(7.67) | t(166) = −0.53 |
| Depression (0–25) | 6.36(5.34) | 6.37(4.73) | t(166) = −0.01 |
| Anxiety (0–21) | 4.91(5.16) | 4.63(4.68) | t(18.85) = 0.32 |
| ADHD (0–6) | 2.74(1.75) | 2.98(1.48) | t(166) = −0.84 |
| Variables (Range) |
Combined DRD2 Risk Allele Carriers
(n = 10) |
Combined DRD2 NonRisk Allele Carriers
(n = 158) |
Test Statistics
Differences |
| M(SD) | M(SD) | ||
| Male | 80% | 62% | x2(1) = 1.31 |
| Age (19–33) | 21.60(2.01) | 22.12(2.38) | t(166) = −0.67 |
| Problematic gaming (1–105) | 35.70(17.89) | 39.92(23.37) | t(166) = −0.56 |
| Interpersonal stress (0–15) | 0.20(0.42) | 0.98(1.96) | t(166) = −1.26 |
| Avoidant coping (6–22) | 12.10(4.75) | 12.39(3.67) | t(166) = −0.24 |
| Impulsivity (22–69) | 43.80(7.76) | 42.82(8.71) | t(166) = 0.35 |
| Depression (0–25) | 4.50(3.34) | 6.48(5.23) | t(166) = −1.18 |
| Anxiety (0–21) | 3.10(1.91) | 4.94(5.13) | t(18.85) = −2.52 *,a |
| ADHD (0–6) | 2.30(0.95) | 2.84(1.71) | t(13.05) = −1.65 a |
Note: Combined DRD2 risk allele carriers refer to individuals carrying both the T allele of DRD2 C957T and the A1 allele of DRD2 Taq1. Combined DRD2 nonrisk allele carriers are those carrying only one or neither of the T allele of DRD2 C957T and the A1 allele of DRD2 Taq1; * p < 0.05. a Because equal variance was not assumed, Welch’s statistical method was used.