Table 1

Established thyroid cancer risk factors and thyroid cancer risk among participants in the multiethnic Bay Area Thyroid Cancer Study

Risk factorCasesControlsORa95% CI
Medical radiationb,c
 Head or neck2082.71.2–6.2
 Another area470.570.16–2.0
 None5805431.0
Benign thyroid diseased,e
 Goiter or nodules134364.73.1–7.2
 Hyperthyroidism19170.550.26–1.2
 Hypothyroidism34350.650.38–1.1
 None of the above4554851.0
Family history of thyroid disease
 Thyroid cancer1636.11.8–21.3
 Goiter or nodules66282.61.7–4.2
 Hyper- or hypothyroidism74531.51.0–2.3
 Other or unknown type39411.00.65–1.6
 None of the above4064291.0
  • a Adjusted for age, race/ethnicity, and education.

  • b More than 5 years before diagnosis/selection.

  • c One control reported radiation to the head/neck and another area.

  • d More than 2 years before diagnosis/selection.

  • e Thirty-three cases and 15 controls reported having been diagnosed with two or more types of benign thyroid disease during their lifetime.