Screening vs. Diagnostic Mammogram: What is the Difference, and Which One Do You Need?

By Kamandeep Chhabra, CCPA, MRT(N) — Director of Operations & Physician Relations, Limeworth X-Ray & Ultrasound, Hamilton

"Mammogram" is a single word, but it actually covers two pretty different appointments. Figuring out whether you need a screening mammogram or a diagnostic one means you book the right test the first time — and get the right care faster. Here’s how I explain the difference to patients.

What They Have in Common

Both are low-dose X-rays of the breast, done by a trained mammography technologist, and both are read by a radiologist. What changes is the reason you’re having one.

A Screening Mammogram — When You Feel Fine

A screening mammogram is a routine check for women with no breast symptoms. Its whole job is to catch cancer early, before you’d ever notice it yourself.

• It’s part of the Ontario Breast Screening Program (OBSP)

• It’s for average-risk women aged 40 to 74, who can book themselves in — no doctor’s referral needed

• It’s recommended every two years for average risk

• It’s a standard set of images — quick and simple

• And it’s no cost with a valid OHIP card

A Diagnostic Mammogram — When There’s a Specific Reason

A diagnostic mammogram is ordered to look into something in particular, and for this one you’ll need a requisition from your doctor or nurse practitioner. It’s the right test if you have:

• A breast symptom — a lump, pain, nipple discharge, or a change in the skin or shape of your breast

• An abnormal or unclear screening result that needs a closer look

• A personal history of breast cancer, or a finding your team is keeping an eye on

A diagnostic mammogram usually takes extra images from more angles, and we often pair it with a breast ultrasound so the radiologist gets the full picture.

The Short Version

If you feel fine and you’re just due for your routine check, you want a screening mammogram — and if you’re 40 to 74, you can book it yourself. If you’ve noticed a symptom or had an abnormal result, don’t wait for routine screening — see your doctor for a diagnostic requisition right away.

One thing I always stress: the OBSP is only for women without symptoms. If something feels off, a screening mammogram isn’t the right route — your doctor should set up a diagnostic work-up instead.

Book Either One in Hamilton

At Limeworth we do both OBSP screening mammograms and diagnostic mammograms, plus breast ultrasound, right here near CF Lime Ridge Mall on the Hamilton Mountain. With fast appointments — Saturdays included — it’s easy to get the imaging you need without a long hospital wait.

For a screening mammogram, if you’re 40 to 74 you can refer yourself. For a diagnostic one, just have your doctor’s requisition ready.

Frequently Asked Questions

Do I need a doctor’s referral for a mammogram in Hamilton?

It depends which one. For an OBSP screening mammogram, women 40 to 74 can book themselves in — no referral needed. For a diagnostic mammogram, you’ll need a requisition from your doctor or nurse practitioner.

I found a lump — should I book a screening mammogram?

No — a lump counts as a symptom, so you need a diagnostic mammogram, which your doctor orders. Please see your provider promptly instead of waiting for routine screening, and they’ll arrange the right imaging.

Is a diagnostic mammogram covered by OHIP?

Yes. When your physician orders it with a valid requisition and you have your OHIP card, diagnostic mammography is covered. We also have a cash fee schedule for anything that falls outside OHIP.

Does a diagnostic mammogram include an ultrasound?

Often, yes. Diagnostic work-ups frequently combine extra mammogram views with a breast ultrasound so the radiologist can fully check the area. We provide both at our Hamilton clinic.

Book Your Mammogram in Hamilton

Limeworth X-Ray & Ultrasound is a proudly OBSP-participating, ICHSC-accredited diagnostic clinic on the Hamilton Mountain, conveniently located near CF Lime Ridge Mall with Dynacare bloodwork right across the hall. Our experienced, compassionate female mammography technologists, modern digital mammography, and fast appointments (including new Saturday availability) make breast screening easy.

To book: Email your phone number and your doctor’s requisition to 849xray@gmail.com, or call 905-574-7755. Women aged 40–74 can self-refer for an OBSP screening mammogram — no doctor’s referral needed.

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