Jasmine McBain-Miller

CT scan exposure before the age of 20 and cancer risk in the Medicare cohort

J.McBain-Miller photo

Supervisors names: Dr Katrina Scurrah, Prof John Mathews

Ionising radiation exposure is known to increase the risk of cancer. There is strong evidence suggesting that the younger a person is at the time of radiation exposure, the greater the lifetime risk of cancer. As the risk of cancer increases with an increase in radiation dose, CT scans are of particular concern because they involve significantly higher radiation doses than traditional X-rays. While the risk of cancer to an individual undergoing a CT scan is still very small, and the exposure is generally medically justified, the high number of CT scans performed within Australia makes it a public health concern.

This project involves estimating the risk of cancer in those who underwent at least one CT scan before the age of 20, compared with those who had not undergone a CT scan before age 20. This project uses the Medicare cohort, containing more than 10 million people, with approximately 680,000 having at least one CT scan before 20 years of age. The cohort was followed from 1985 to 2012 for cancer diagnosis. The large sample size and long follow-up duration give strong statistical power to estimate even small increases in the risk of cancer.


PhD scholarship and funding body: Australian Government Research Training Program Scholarship