Cases | Controls | Crude OR (95 % CI) | AOR (95 % CI)a | AOR (95 % CI)b | |||
---|---|---|---|---|---|---|---|
Variables | N = 296 | N = 296 | |||||
N | (%) | N | (%) | ||||
Hair dyes | |||||||
No | 197 | (66.6) | 231 | (78.0) | 1.00 | 1.00 | 1.00 |
Yes | 95 | (32.1) | 64 | (21.6) | 1.74 (1.21–2.53)* | 1.86 (1.21–2.82)* | 2.15 (1.32–3.57)* |
Missing | 4 | 1 | 4.69 (0.69–92.10) | 5.03 (0.73–98.83) | 5.40 (0.76–108.02) | ||
Age of first use (yrs) | |||||||
Never | 197 | (66.6) | 231 | (78.0) | 1.00 | 1.00 | 1.00 |
≥60 | 24 | (8.1) | 21 | (7.1) | 1.34 (0.72–2.49) | 1.23 (0.63–2.39) | 1.52 (0.71–3.30) |
50- < 60 | 28 | (9.5) | 21 | (7.1) | 1.56 (0.86–2.87)* | 2.19 (1.08–4.60)* | 2.64 (1.16–6.36)* |
<50 | 29 | (9.8) | 16 | (5.4) | 2.13 (1.14–4.11)* | 2.32 (1.21–4.61)* | 2.25 (1.01–5.19)* |
Missing | 18 | 7 | 3.02 (1.28–7.89) | 2.70 (1.04–7.86) | 4.29 (1.32–16.72) | ||
P for trend | <0.01 | <0.01 | <0.01 | ||||
Years of use (years) | |||||||
Never | 197 | (66.6) | 231 | (78.0) | 1.00 | 1.00 | 1.00 |
≤10 | 40 | (13.5) | 35 | (11.8) | 1.34 (0.82–2.20) | 1.49 (0.87–2.59) | 1.57 (0.82–3.03) |
>10 | 37 | (12.5) | 22 | (7.4) | 1.97 (1.13–3.50)* | 2.10 (1.15–3.92)* | 2.54 (1.23–5.41)* |
Missing | 22 | 8 | 3.22 (1.46–7.87) | 3.23 (1.36–8.52) | 5.43 (1.82–20.13) | ||
P for trend | 0.02 | <0.01 | <0.01 | ||||
Frequency of use (times per year) | |||||||
Never | 197 | (66.6) | 231 | (78.0) | 1.00 | 1.00 | 1.00 |
≤6 | 41 | (13.9) | 32 | (10.8) | 1.50 (0.91–2.49) | 1.64 (0.95–2.85) | 1.73 (0.91–3.32) |
>6 | 35 | (11.8) | 25 | (8.4) | 1.64 (0.95–2.86) | 1.97 (1.07–3.69)* | 2.65 (1.26–5.78)* |
Missing | 23 | 8 | 3.37 (1.53–8.19) | 2.82 (1.23–7.08) | 3.85 (1.41–11.74) | ||
P for trend | 0.02 | <0.01 | <0.01 | ||||
Year of first use | |||||||
No | 197 | (66.6) | 231 | (78.0) | 1.00 | 1.00 | 1.00 |
After 1980 | 5 | (1.7) | 3 | (1.0) | 1.95 (0.47–9.62) | 1.25 (0.23–6.83) | 0.89 (0.11–5.90) |
Before 1980 | 76 | (25.7 | 55 | (18.6) | 1.62 (1.09–2.41)* | 1.87 (1.21–2.90)* | 2.16 (1.28–3.68)* |
Missing | 18 | 7 | 3.02 (1.28–7.89) | 2.71 (1.04–7.89) | 4.32 (1.33–16.87) | ||
Regular exercise | |||||||
No | 126 | (42.6) | 120 | (40.5) | 1.00 | 1.00 | 1.00 |
Yes | 166 | (56.1) | 168 | (56.8) | 0.93 (0.67–1.28) | 0.99 (0.69–1.43) | 1.01 (0.64–1.59) |
Missing | 4 | 8 | 0.48 (0.02–5.03) | none | 1.03 (0.66–1.62) | ||
Frequency of exercise (times per week) | |||||||
No | 126 | (42.6) | 120 | (40.5) | 1.00 | 1.00 | 1.00 |
1-6 | 56 | (18.9) | 65 | (22.0) | 1.22 (0.79–1.89) | 0.94 (0.58–1.53) | 1.01 (0.55–1.86) |
≥7 | 110 | (37.2) | 103 | (34.8) | 0.98 (0.68–1.42) | 1.02 (0.68–1.54) | 0.97 (0.58–1.62) |
Missing | 4 | 8 | 0.48 (0.12–1.55) | 1.57 (0.25–12.15) | 0.97 (0.11–8.50) |