Other
Hypothyroidism: Symptoms, Dangers, and Treatments.
Clear, readable information about the causes and symptoms of hypothyroidism is offered by two physicians.
Mayo Clinic
Mayo Clinic: Graves' Disease
This site from the MayoClinic.com provides a great overview of the form of hyperthyroidism known as Graves' disease. The sections in the article include signs and symptoms, causes, screening, diagnosis, treatment, and self-care.
Other
Thyroid Goiter: Definition, Diagnosis, Dangers
Just what is a goiter, and what causes it? Two physicians explain on this page which gives general information about the treatment of goiters.