Open AccessCross-Sectional versus Longitudinal Investigations of the Diet-Cancer Relation
Author(s) -
Piet A. van den Brandt,
R. Alexandra Goldbohm,
A.J.M. van Loon,
F.J. Kok
Publication year - 1990
Publication title -
epidemiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.901
H-Index - 173
eISSN - 1531-5487
pISSN - 1044-3983
DOI - 10.1097/00001648-199009000-00011
Subject(s) - medicine , colorectal cancer , breast cancer , red meat , odds ratio , cross sectional study , odds , cancer , prospective cohort study , cohort study , longitudinal study , case control study , cohort , logistic regression , pathology
Within a prospective cohort study on diet and cancer, information was collected on cancer prevalence and baseline meat consumption. A nested case-control study on meat and cancer was conducted with 656 prevalent colorectal cases, 1,894 breast cancer cases, and 4,701 controls. When analyzed cross-sectionally, prevalence odds ratios for eating meat rarely versus regularly were 2.08 for female colorectal and 1.75 for breast cancer. In the longitudinal analysis, cases who started consuming meat rarely after diagnosis were excluded, resulting in odds ratios of 0.51 for female colorectal and 1.17 for breast cancer. These opposite findings highlight the problem of cross-sectional designs.