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Multiple logistic regressions of factors associated with chronic headache
| Factors | Significance | Estimate relative risk (95 % CI) |
|---|---|---|
| Age | <0.0001 | 1.03 (1.02–1.04) |
| Sex (female vs. male) | <0.0001 | 1.85 (1.49–2.31) |
| Marriage (married vs. not married) | 0.020 | 1.41 (1.06–1.89) |
| Education (high education & more vs. illiterate & low) | 0.014 | 1.52 (1.09–2.12) |
