Table 1.
Hair cortisol concentrations obtained using different methods. Data of “Part-of-body” and “Hair color” were taken from Yamanashi et al. [1] for comparison.
| Variable | Correlation | M (pg/mg hair) | SD | CV (%) |
|---|---|---|---|---|
| (a) Body part-arm only (N = 14) | ||||
| Arm1 | 0.70* | 14.5 | 2.74 | 10.5 |
| Arm2 | 14.6 | 4.03 | ||
| (a) Body part | ||||
| Arm | 0.61–0.71* | 16.8 | 4.90 | 17.9* |
| Side | 20.8 | 7.44 | ||
| Back | 19.4 | 6.11 | ||
| (b) Reproducibility (N = 22) | ||||
| First | 0.92* | 22.9 | 6.73 | 8.20 |
| Second | 23.9 | 7.93 | ||
| (b) Preserve 1 yr (N = 29) | ||||
| First | 0.76* | 15.9 | 3.47 | 7.40 |
| Second | 15.4 | 3.04 | ||
| (b) Preserve 2 yrs (N = 16) | ||||
| First | 0.90* | 14.5 | 2.83 | 5.10 |
| Second | 14.4 | 2.86 | ||
| (c) Fineness of homogenized hair (N = 19) | ||||
| Fine | 0.85* | 24.5 | 9.86 | 25.0* |
| Coarse | 18.9 | 13.0 | ||
| (d) Hair weight (N = 6) | ||||
| 20 mg | 0.68–0.98 | 24.0 | 3.68 | 22.3* |
| 10 mg | 25.8 | 3.56 | ||
| 5 mg | 27.9 | 3.74 | ||
| 2.5 mg | 29.2* | 3.81 | ||
| 1 mg | 40.8* | 5.14 | ||
| (e) Extraction time (N = 11) | ||||
| 1 h | 0.73–0.82* | 14.5 | 1.61 | 18.2* |
| 8 h | 18.0* | 2.26 | ||
| 24 h | 20.6* | 2.83 | ||
| (f) Drying (N = 26) | ||||
| Nitrogen gas | 0.76* | 15.3 | 3.09 | 6.80 |
| Vacuum oven | 14.8 | 2.65 | ||
| (–) Hair color | 0.42 | |||
| Black | 12.6 | 3.40 | 50.0* | |
| White | 26.5 | 6.91 | ||
| Average (pg/mg hair) | SD | CV (%) | |
|---|---|---|---|
| (g) Variances (N = 73) | |||
| Within individuals | 20.9 | 5.03 | 30.1 |
| Between individuals | 24.0 | ||
M, mean; SD, standard deviation; CV, coefficient of variation.
*
p < 0.05.