Table 1a.

Study descriptions of self-reported intentional weight loss, weight cycling, and the risk of endometrial cancer

Author, year	Study type	Population	Study design	Recruitment year	Endometrial cancer diagnosis year	Developed endometrial cancer	Total N	Weight status measures	Weight cycling/weight loss definition
Self-reported intentional weight loss
Luo, 2017	prospective cohort	WHI (U.S)	WHI cohort without history of cancer, did not have hysterectomy, did not have endometrial cancer diagnosis between baseline and year-3 visit cases: all incident endometrial cancer occurrences diagnosed after the year-3 visit	1993–1998	from the year-3 visit to the first of either an endometrial cancer diagnosis, a date of hysterectomy, a date of death, loss to follow-up, or end of current follow-up (9/30/2015)	566	36793	Measured at baseline and year 3 follow-up	stable weight: within ±10lbs weight gain (≥10 lbs) weight loss (≥10 lbs) intentional; unintentional
Parker, 2003	prospective cohort	Iowa Women’s Health study (U.S)	Iowa Women’s Health Study randomly selected women between the age 55–69 in January 1986, had a valid driver’s license in 1985 cases: endometrial cancer was identified by computer linkage with state health registry of Iowa	1986	1993–2000	142	21707	the 1992 questionnaire	never lost ≥20lbs, intentional loss, unintentional loss, ≥ intentional plus ≥ unintentional
Weight Cycling
Welti, 2017	cohort	WHI observation (U.S)	WHI observational study, postmenopausal (50–79 yrs), no missing information on weight change, baseline covariates, or reported history of cancers at baseline, or reported hysterectomy at baseline	1993–1998	1994–2014	788	47897	baseline questionnaire	weight cycling: intentional weight loss and subsequent regain; stayed the same (<10lbs); steady gained; lost weight as an adult and kept it off; weight went up and down again ≥10lbs (1–3×, 4–6×, 7–10×, >10×)
Nagle, 2013	population-based case-control	Australia	cases: newly diagnosed, histologically confirmed, epithelial endometrial cancer diagnosed controls: randomly selected from voter system matched by residence state and age + participants from another study	2005–2007	2005–2007	1398	2936	telephone interview/ self-administered questionnaire	weight cycling: never intentionally lost > 9kg and regained within 12 month; lost >9 kg and kept it off; >1× intentionally lost >9 kg and regain within 12 months
Stevens, 2012	prospective cohort	ACS cancer prevention study II nutrition cohort (U.S)	CPS-II Nutrition Cohort (50–74 yrs)	1992/1993	follow-up started in 1997 and every 2 years until the date of endometrial cancer diagnosis, death, date of the last returned survey, or June 30, 2007, whichever came first	559	38148	baseline questionnaire	weight cycling was asked “how many times in your life have you purposefully …” weight cycling: # of lost ≥10lbs and regained: non-cycler, 1–4 times, 5–9 times ≥10 times
Trentham-Dietz, 2006	population-based case-control	Wisconsin (U.S)	cases: Wisconsin cancer registry; controls: random selected from population lists of drivers and Medicare beneficiaries, matched by age distribution	1992–1995	cases: 1/1/1991–12/31/1994	740	3082	structured telephone interview	weight cycling: intentionally lost >20lbs and regain more than half within 1 yr, frequency, age at it last happened