Table 3.
Differences in variables of interest across Trichotillomania (TTM) subtypes.
| Variable |
Class 1 TTM-Absent/Controls (n = 121) |
TTM Subtype 1 (n = 27) |
TTM Subtype 2 (n = 81) |
TTM Subtype 3 (n = 50) |
Statistic – Overall |
Post hoc tests |
|---|---|---|---|---|---|---|
| Demographics and Clinical Measures | ||||||
| Age, yrs | 30.588 (0.95) | 33.136 (2.288) | 29.186 (1.041) | 30.37 (1.452) | Chi-square = 2.769; df = 3 p = 0.429 (corrected p value = 1) | |
| Sex, proportion females | 0.846 | 0.885 | 0.815 | 80.1 | Chi-square = 0.857; df = 3; p = .836 (corrected p value = 1) | |
| Duration of illness, yrs | 18.27 (1.426) | 19.258 (2.33) | 17.119 (1.211) | 17.271 (1.592) | Chi-square = 0.909; df = 3; p = 0.823 (corrected p value = 1) | |
| ADHD symptoms (Adult ADHD Self-Report Scale Screener total scores) | 1.359 (0.149) | 1.652 (0.339) | 2.232 (0.215) | 2.302 (0.268) | Chi-square = 16.244; df = 3; p = .001 (corrected p value = .013) | Subtype 2 compared to controls (p = .001) and Subtype 3 compared to controls (p = .003) |
| Impairment due to BFRB (Sheehan Disability Scale total score) | 4.389 (0.515) | 7.54 (1.434) | 7.059 (0.789) | 10.776 (1.159) | Chi-square = 29.705; df = 3; p < .001 (corrected p value < .001) | Subtype 1 compared to controls (p = .039) Subtype 2 compared to controls (p = .005) Subtype 3 compared to controls (p < .001) Subtype 3 compared to subtype 2 (p = .008) |
| Short Mood and Feelings Questionnaire | 3.599 (0.386) | 6.684 (1.104) | 5.111 (0.599) | 7.783 (0.872) | Chi-square = 24.298; df = 3; p < .001 (corrected p value < .001) | Subtype 1 compared to controls (p = .008) Subtype 2 compared to controls (p = .034) Subtype 3 compared to controls (p < .001) Subtype 3 compared to subtype 2 (p = .012) |
| The Emotion Regulation Questionnaire – Reappraisal Subscale | 28.112 (0.652) | 26.062 (1.471) | 28.068 (0.776) | 25.337 (1.118) | Chi-square = 6.117; df = 3; p = .106 (corrected p value = 1) | |
| Suppression Subscale | 12.891 (0.473) | 14.846 (1.05)) | 13.197 (0.574) | 14.283 (0.746) | Chi-square = 4.577; df = 3; p = .206 (corrected p value = 1) | |
| Distress Tolerance Scale total score | 56.685 (1.129) | 51.615 (2.816) | 52.919 (1.46) | 43.629 (1.852) | Chi-square = 36.509; df = 3; p < .001 (corrected p value < .001) | Subtype 3 compared to controls (p < .001) compared to Subtype 1 (p = .018) and compared to Subtype 2 (p < .001) Subtype 2 compared to controls (p = .041) |
| Adult sensory profile: Sensory Sensitivity subscale | 30.749 (0.701) | 37.684 (1.808) | 34.189 (0.966) | 36.063 (1.278) | Chi-square = 24.303; df = 3; p < .001 (corrected p value < .001) | Subtype 1 compared to controls (p < .001) Subtype 2 compared to controls (p = .004) Subtype 3 compared to controls (p < .001) |
| Perfectionism (Frost Perfectionism in Adults total score) | 80.011 (1.961) | 80.032 (4.274) | 84.746 (2.464) | 95.562 (3.047) | Chi-square = 19.468; df = 3; p < .001 (corrected p value = .003) | Subtype 3 compared to controls (p < .001) compared to Subtype 1 (p = .003) and compared to Subtype 2 (p = .006) |
| Comorbidity | ||||||
| ADHD diagnosis, proportion meeting diagnostic criteria | 0.017 | 0 | 0 | 0.061 | Chi-square = 5.082; df = 3; p = .166 (corrected p value = 1) | |
| Obsessive Compulsive Disorder (OCD) diagnosis, proportion with diagnosis | 0.017 | 0.074 | 0.037 | 0.141 | Chi-square = 6.890; df = 3; p = .075 (corrected p value = .830) | |
| Family History | ||||||
| Family History of OCD, proportion with | 0.0125 | 0 | 0.037 | 0.020 | Chi-square = 7.198; df = 3; p = .066 (corrected p value = .790) | |
| Family history of Alcohol use disorder, proportion with | 0.182 | 0.146 | 0.178 | 0.213 | Chi-square = 0.422; df = 3; p = .936 (corrected p value = 1) | |
| Family history of Substance use disorder, proportion with | 0.074 | 0.073 | 0.099 | 0.142 | Chi-square = 1.461; df = 3; p = .691 (corrected p value = 1) | |
| Cognitive Measures | ||||||
| Barratt Impulsivity Scale total | 56.12 (1.103) | 58.593 (2.398) | 59.935 (1.266) | 64.282 (1.613) | Chi-square = 18.097; df = 3; p < .001 (corrected p value = .006) | Subtype 3 compared to controls (p < .001), compared to Subtype 1 (p = .049) and compared to subtype 2 (p = .034) Subtype 2 compared to controls (p = 0.023) |
| Extra-dimensional set-shifting errors | 9.491 (0.963) | 12.719 (2.32) | 9.874 (1.225) | 10.18 (1.653) | Chi-square = 1.674; df = 3; p = .643 (corrected p value = 1) | |
| Stop-signal reaction times | 207.762 (6.387) | 239.64 (30.529) | 220.784 (11.386) | 247.528 (25.006) | Chi-square = 3.801; df = 3; p = 1 (corrected p value = 1) | |
Values are Mean (±SE) unless stated otherwise; only significant results are displayed under post-hoc tests.