Annual Screening Blood Tests

Choosing Wisely Canada recommendation #12: Do not do annual screening blood tests unless directly indicated by the risk profile of the patient.

——

Clinical scenario: A 55-year-old patient arrives for a routine blood pressure check. Their blood pressure is well-controlled, they feel well, and have no new symptoms. At the end of the visit, the clinician orders a complete blood count (CBC) out of routine, even though there is no clear clinical reason. However, the patient agrees, feeling that it is a way to stay proactive about their health.

A few days later, the lab results return, showing a mildly abnormal white blood cell count. It’s likely benign, but the clinician feels they must now follow up. A phone call is scheduled, during which the patient asks questions and shares concerns. The clinician reassures them, and orders repeat tests “to be safe.” This may lead to a specialist referral or more unnecessary lab tests, pulling in more time and resources—not because the patient was unwell, but because of an initial test that lacked a clear medical indication.

The patient, who had taken time off work for the original visit, now finds themselves coordinating further appointments and calls during work hours, adding avoidable disruption and stress to their week. They may have spent time worrying needlessly.

While seemingly brief as isolated events, these unnecessary actions add up over time. In a clinic of 10 clinicians, avoiding routine CBCs in patients without clear clinical indications could free up 20 days per year—time that could be reallocated to high-value care and patient needs that truly warrant clinical attention. This might include offering more appointments for patients with complex needs, supporting team-based care, following up on mental health concerns, or improving access in underserved communities.