Refer to Table 4, in which the association between hair relaxer use and uterine cancer is stratified by menopausal status. Focus on post-menopausal women only, and calculate the attributable risk among the exposed (risk difference) for Heavy users relative to the Never/light group (nonexposed). Ignore the moderate group for this comparison. Express your answer as cases per 100,000 person-years. (2pts)Table 4
Hazard ratios (95% confidence intervals) for uterine cancer in relation to hair relaxer use by menopausal status, 1997-2019.
able[[,Premenopausal,Postmenopausal],[,Person-years,N cases,Multivariable HR^(a)(95%CI),Person-years,N cases,Multivariable HR^(a)(95%CI)
Table 4 Hazard ratios (95% confidence intervals) for uterine cancer in relation to hair relaxer use by menopausal status, 1997-2019.
Premenopausal
Postmenopausal
Person-years
N cases
Multivariable HR(95% CI)
Person-years
N cases
Multivariable HR(95% CI)
Hair relaxer use Never/light 36,285 12 1.00 (ref) 42,725 23 1.00 (ref) Moderate 248,479 58 0.84 (0.45, 1.58) 165,713 123 1.60 (1.01, 2.53) Heavy 159,662 31 0.63 (0.32, 1.24) 127,702 85 1.64 (1.01, 2.64) Duration of use Never/light 36,285 12 1.00 (ref) 42,725 23 1.00(ref) 14 years 15,904 8 1.36 (0.55, 3.38) 16,058 7 0.87 (0.37, 2.05) 59 years 52,625 12 0.90 (0.40, 2.02) 29,127 15 1.09 (0.57, 2.12) 1014 years 122,517 18 0.66 (0.31, 1.41) 43,011 2.21 (1.30, 3.75) 1519 years 122,108 20 0.65 (0.31, 1.34) 54,251 31 1.49 (0.85, 2.59) 20 years 94,988 31 0.74 (0.38, 1.47) 150,970 116 1.71 (1.08, 2.72) Frequency of useb Never/light 36,285 12 1.00 (ref) 42,725 23 1.00 (ref) 1-2 times/year 25,326 7 0.83 (0.32, 2.13) 26,981 21 1.59 (0.87, 2.91) 3-4 times/year 104,638 35 1.00 (0.51, 1.94) 97,619 72 1.56 (0.96, 2.53) 5-6 times/year 124,694 20 0.55 (0.27, 1.14) 84,959 65 1.85 (1.13, 3.03) 7 times/year 150,760 25 0.65 (0.32, 1.31) 81,498 48 1.47 (0.88, 2.46) Never or light use is defined as 14 years, 2 times/year; heavy use is defined as 15 years, 5 times/year; remainder are moderate users (14 years, >3 times/year; 514 years, any frequency;or15years,<5 times/year) HR, hazard ratio; CI, confidence interval. HRs adjusted for age, period, education (16, 1315, 12 years), physical activity (none, <5, 5 h per week), parity (no children, 1 child, 2 children, 3 children), smoking status (never, past, current), body mass index (continuous), alcohol consumption (<1, 16, or 7 drinks per week), oral contraceptive use (5 years, <5 years, never), age of menarche (14, 13, 12, 11 years), residential region (Northeast, South, Midwest, West), female hormone use (progestin alone or unknown, estrogen plus progestin but never estrogen alone,estrogen alone,never hormone use). Frequency of use was missing for 2 premenopausal cases and 2 postmenopausal cases