Home > Publications . Search All . Browse All . Country . Browse PSC Pubs . PSC Report Series

PSC In The News

RSS Feed icon

Thompson says criminal justice policies led to creation of prison gangs like Aryan Brotherhood

Schmitz finds job loss before retirement age contributes to weight gain, especially in men

Kimball says Fed should get comfortable with "backtracking"

Highlights

Overview of Michigan's advanced research computing resources, Monday, June 27, 9-10:30 am, BSRB - Kahn Auditorium

U-M's Data Science Initiative offers expanded consulting services via CSCAR

Elizabeth Bruch promoted to Associate Professor

Susan Murphy elected to the National Academy of Sciences

Next Brown Bag

PSC Brown Bags
will resume fall 2016

Sampling Strategies for Prospective Studies of Menstrual Function

Publication Abstract

Lisabeth, L., Sioban D. Harlow, X. Lin, B. Gillespie, and M. Sowers. 2004. "Sampling Strategies for Prospective Studies of Menstrual Function." American Journal of Epidemiology, 159(8): 795-802.

Little information is available about optimal sampling strategies for prospective studies of menstrual function. Sample size and study duration for menstrual studies have often been driven as much by feasibility and cost as by statistical principles, with follow-up lasting 6 months to 2 years and sample size ranging from 100 to 500 women. Whether these studies are sufficiently powered to address common study objectives has not been adequately evaluated, and sample size estimates rarely account for the repeated nature of menstrual cycle data. Using data from the Tremin Trust (a study of menstrual function across the reproductive life span initiated in Minneapolis, Minnesota, in 1935 with data collected through 1977), the authors determined sampling strategies for assessing differences in mean cycle length between two exposure groups and for assessing change in mean cycle length across the reproductive life span. Following a larger number of women for 1-2 years is optimal for studies of host and environmental exposures that alter menstrual function. In contrast, following fewer women for an extended period of time, for example, 4-5 years, is optimal when studying how menstrual patterns vary across the reproductive life span in different populations.

Browse | Search : All Pubs | Next