CCFP priority topic 97 of 105
Thyroid on the CCFP exam
3 key features, the mistakes that cost marks, and a practice question.
Checked by a Canadian family physician, MD, CCFP. Updated October 20, 2026.
What the exam tests
Key features
The CFPC’s 3 key features for Thyroid. Each one below has how the exam asks it, the common mistakes and the approach.
Practice question
Try one before you read
A real case from the bank, in the new short-menu format. Answer it first. Then read the key features.
Key feature 1 of 3
Who to test
Test for thyroid disease only when the result is likely to be abnormal.
CFPC skill Clinical reasoning, selectivityPhase InvestigationSources Canadian Task Force on Preventive Health Care, Choosing Wisely Canada, Health Canada
On the exam
A new mother is shaky, tired and below her pre-pregnancy weight. Expect a short menu (pick several from a list) of tests.
Pick the tests worth sending today.
Common mistakes
Calling it new-baby stress and sending her home. Or the full panel: free T3, thyroid antibodies and an ultrasound. Start with one thyroid-stimulating hormone (TSH), and add free T4 only if it is abnormal.
Approach
- Test when symptoms point to the thyroid: unusual tiredness, weight loss or gain, irregular periods, or a goitre (an enlarged gland).
- With vague symptoms, lower your bar in higher-risk groups. The CFPC flags older adults, new mothers, atrial fibrillation and other gland disease.
- Thyroid autoimmune disease can travel with type 1 diabetes, pernicious anemia or adrenal failure.
- Do not screen adults who have no symptoms and are not pregnant. The Task Force and the family medicine Choosing Wisely list both advise against it.
- Start with TSH alone. If it is abnormal, free T4 (the main thyroid hormone) helps confirm the diagnosis.
- Skip routine thyroid antibodies, free T3 and ultrasound at the start. Ultrasound shows lumps, not how well the gland works.
- Disease of the pituitary, the gland that makes TSH, makes TSH unreliable. Use free T4 there.
| Patient | Test? | Start with |
|---|---|---|
| Adult 18 or over, no symptoms, not pregnant | No. The Task Force advises against screening. | Nothing |
| Clear symptoms or a goitre | Yes | TSH alone |
| Vague symptoms and a higher risk | Yes | TSH alone |
| Past thyroid disease, lithium or amiodarone, neck radiation, pituitary disease | Outside the Task Force advice. Test on clinical need. | TSH. Free T4 if the pituitary is diseased. |
Key feature 2 of 3
When to repeat TSH
In known thyroid disease, time each TSH to a decision, not to a calendar.
CFPC skill Clinical reasoning, selectivityPhase InvestigationSources Health Canada, Choosing Wisely Canada
On the exam
A care home resident with dementia has a TSH that rose after calcium was given with his levothyroxine. Expect one best answer.
Pick the next step and when to recheck.
Common mistakes
Raising the dose before the calcium is moved, or rechecking at 2 to 4 weeks. Monthly draws on a stable dose are wrong too, and so is waiting for symptoms he cannot report.
Approach
- After starting or changing the dose, check TSH in 6 to 8 weeks. Repeat at that interval until it is normal.
- When first treating older adults or people with heart disease, start low. Raise the dose every 3 to 6 weeks until TSH is normal.
- Once stable, check at least yearly, or sooner when health, medicines or the brand change.
- Mild disease not yet treated: check TSH and symptoms yearly.
- Adjust the dose by TSH, not free T4 or free T3, unless the pituitary is diseased.
- A rise on a steady dose: find the cause first. Calcium, iron, antacids and proton pump inhibitors block absorption. Take levothyroxine at least 4 hours apart from them.
- Too much levothyroxine strains the heart and thins bone. Watch for a fast or irregular rhythm, above all in older adults.
| Situation | When | Know this |
|---|---|---|
| Dose started or changed | 6 to 8 weeks later, until normal | An early result invites a needless second change. |
| Stable on treatment | At least yearly | Sooner after a new drug, a brand switch or a change in health |
| Pregnant, on levothyroxine | About every 4 weeks in the first half. At least once at 26 to 32 weeks. | The dose often needs to rise. |
| After delivery, on levothyroxine | 6 to 8 weeks after the birth | Go back to the pre-pregnancy dose first. |
| Infant with congenital hypothyroidism | Every 1 to 2 months in the first year | Check T4 with TSH. TSH can lag behind. |
Key feature 3 of 3
Examining the gland
Feel the thyroid with the right method so that a small lump is not missed.
CFPC skill Procedure skillsPhase PhysicalSources Choosing Wisely Canada
On the exam
A care aide finds a neck lump on a man after a stroke. Expect a short menu (pick several from a list) of exam steps.
Pick the steps of the exam.
Common mistakes
A flat palm from the front, or lying him flat. Water for the swallow when his swallowing plan forbids thin fluids. The tongue-out and arms-up tests answer other questions.
Approach
- Seat the patient upright. Look at the neck with the chin slightly raised, then again during a swallow.
- Stand behind and bend the neck slightly forward to relax the muscles. Find the cricoid, the firm ring just below the Adam's apple. The narrow middle of the gland sits just under it.
- Use the pads of two fingers on each side, close to the midline. Feel each lobe in turn.
- Ask for a swallow. The gland rises under your fingers, and a nodule moves up with it.
- If thin fluids are unsafe, use a dry swallow. Do not give water against a swallowing plan.
- Note size, firmness, tenderness and any lump. Then feel the neck nodes.
- A lump you can feel is what earns an ultrasound. Abnormal blood tests alone do not.
Flashcards
Answer it first, then check.
KF 1A healthy 40-year-old with no symptoms asks for a thyroid test. Do you order it?
No. The Task Force advises against screening adults who have no symptoms and are not pregnant. Source: Canadian Task Force on Preventive Health Care
KF 1TSH is low in a patient with palpitations. Which test confirms it?
Free T4. An ultrasound shows structure, not function, so it does not confirm anything here. Source: Health Canada, Choosing Wisely Canada
KF 2You raise the levothyroxine dose today. When is the next TSH?
In 6 to 8 weeks. Repeat at that interval until the TSH is normal. Source: Health Canada
KF 2Same dose for two years, feeling well. How often is TSH checked?
At least once a year, or sooner if health, medicines or the brand change. Source: Health Canada
KF 2Levothyroxine and calcium carbonate are given together each morning. What do you advise?
Separate them by at least 4 hours. Then recheck TSH 6 to 8 weeks later. Source: Health Canada
KF 2She takes levothyroxine and is newly pregnant. How often is TSH checked?
About every 4 weeks in the first half, then at least once between weeks 26 and 32. Source: Health Canada
KF 3Where do you stand to feel a thyroid nodule, and what do you ask?
Behind the seated patient, finger pads near the midline. Ask for a swallow: a nodule moves up.
KF 3Abnormal TSH, but you feel nothing in the neck. Order an ultrasound?
No. Ultrasound is for a lump you can feel, not for abnormal blood tests. Source: Choosing Wisely Canada
FAQ
Should free T4 and free T3 go with every TSH?
No. TSH alone screens and guides the dose. Free T4 helps confirm an abnormal TSH. It also guides treatment when pituitary disease makes TSH unreliable. Free T3 adds nothing when you screen for or treat an underactive gland.
Does the Task Force advice mean I never test someone without symptoms?
No. It covers adults 18 and over who have no symptoms and are not pregnant, older adults included. It leaves out past thyroid disease, lithium or amiodarone, neck radiation and pituitary disease. Pregnancy is outside it too.
Do thyroid antibodies need repeating?
Rarely. A positive result points to an autoimmune cause and a higher risk of hypothyroidism. Autoimmunity lasts, so a repeat antibody level seldom changes care. Follow the TSH instead.
Can supplements throw off a thyroid result?
Yes. Biotin can make thyroid tests read falsely high or low, more so at high doses. Ask the patient to stop it at least 2 days before the blood test.
Sources
Written from the CFPC Assessment Objectives and Canadian guidelines first. Checked by a Canadian family physician, MD, CCFP.
Last reviewed October 20, 2026For exam study. Not advice for a patient in front of you.
- Assessment Objectives for Certification in Family Medicine, 2nd editionCollege of Family Physicians of Canada · 2020
- Published prevention guidelinesCanadian Task Force on Preventive Health Care
- Choosing Wisely recommendationsChoosing Wisely Canada
- Drug Product DatabaseHealth Canada