. Author manuscript; available in PMC: 2024 May 1.

Published in final edited form as: F S Sci. 2023 Apr 5;4(2):172–180. doi: 10.1016/j.xfss.2023.03.006

Table 2.

Associations between keloids, hypertrophic scars, and fibroid incidence among 1,230 participants in the Study of Environment, Lifestyle & Fibroids (SELF), Detroit, Michigan, 2010–2018.

				Hazard ratio (95% confidence interval)
Exposure category	No. exposed (n = 1,230)	Incident cases (n = 293)	Person-years (n = 5,312)	Minimally adjusted^a	Fully adjusted^b
Keloid scar
No	1031	242	4432	Referent	Referent
Yes	199	51	880	1.03 (0.77, 1.39)	1.04 (0.77, 1.40)
Any abnormal scarring^c
No	652	147	2807	Referent	Referent
Yes	578	146	2505	1.08 (0.86, 1.35)	1.10 (0.88, 1.38)

Cox model with age as the time scale with no further covariate adjustment.

Cox model with age as the time scale further adjusted for age at menarche (≤10, 11, 12, 13, or ≥14 years), and time-varying parity (0, 1–2, or ≥3 births), years since last birth (<3 or ≥3 years ago including no births), years since last use of injection contraceptive (<2 or ≥2 years including never), household income (<$20,000 or ≥$20,000 per year), current smoker (no or yes), and body mass index (<30.0, 30.0-<35.0, 35.0-<40.0, or ≥40.0 kg/m²).

Report of either keloid or hypertrophic scar.