Related Experiment Video
Updated: Apr 6, 2026

In Vivo and Ex Vivo Approaches to Study Ovarian Cancer Metastatic Colonization of Milky Spot Structures in Peritoneal Adipose
Published on: October 14, 2015
A case-control study of breast cancer risk in nurses from Northeastern Ontario, Canada
Stacey A Santi1, Margaret L Meigs2, Yantao Zhao2
1Epidemiology, Outcomes and Evaluation Research, Northeast Cancer Centre, Health Sciences North, Sudbury, ON, P3E 5J1, Canada. ssanti@hsnsudbury.ca.
Purpose:
Previously published findings have documented increased breast cancer risks associated with the nursing profession. The aim of the present study was to assess whether an increased risk of breast cancer was associated with nursing in a population-based case-control breast cancer study of women in Northeastern Ontario, Canada.
Methods:
A total of 1519 women (1380 never-nurses: 716 controls and 664 cases; 139 ever-nurses: 59 controls and 80 cases) were included in the present study. Study participants filled out a detailed questionnaire which included a history of smoking, general health information, breast cancer risk factors, and a detailed occupational history.
Results:
Ever-nurses were at higher, but nonsignificant risk of breast cancer compared to never-nurses (adjusted OR 1.39, 95 % CI 0.93-2.07). Ever-nurses who worked for longer than 10 years were at a significantly increased risk of breast cancer compared to never-nurses (adjusted OR 1.70, 95 % CI 1.04-2.79). A nonsignificant, but increased risk of breast cancer was observed in ever-nurses who worked full-time compared to never-nurses (OR 1.52, 95 % CI 0.92-2.52), while nurses who worked part-time, or both part-time and full-time were not at increased risk. Ever-nurses who worked in a hospital setting had a significantly increased risk of breast cancer (OR 1.65, 95 % CI 1.04-2.62) compared to never-nurses.
Conclusions:
The results indicate that the nurses in the present study population are at increased risk of breast cancer. A prolonged duration of nursing years and prolonged intensity (being a full-time nurse) are factors associated with this increased risk.
Related Concept Videos
Bias in Epidemiological Studies
Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One...
Cancer Survival Analysis
Cancer Prevention
Some...
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...

