Table 1: Characteristics of case and control.

CharacteristicCasesControls

Sample size ( )105110
Age (mean ± SD)
Age groups
 <30.5 years50 (47.6%)58 (52.7%)
 ≥30.5 years55 (52.4%)52 (47.3%)
Sex
 Female80 (76.2%)89 (80.9%)
 Male 25 (23.8%)21 (19.1%)
Place of residence
 Urban 52 (49.5%)58 (52.7%)
 Rural 53 (50.5%)52 (47.3%)
Level of education
 Below high school diploma44 (41.9%)44 (40.0%)
 Above high school diploma61 (58.1%)66 (60.0%)
Duration of sun light exposure (mean ± SE)  min/day  min/day
Groups of sun light exposure
 0–120 min/day83 (79.0%)90 (81.8%)
 ≥120 min/day22 (21.0%)20 (18.2%)