“It’s simple, so no one will make a mistake.”
That is the dangerous part.

00 / BEFORE WE START

Just three terms first.

I worked for a clinical laboratory company that performed tests for hospitals and clinics: blood tests, microbiology, pathology, and more. The medical institution sent both the instructions and the material to be examined.

Specimen verification means confirming that the specimen in front of you belongs to the patient and tests on the order—and that every required container is present in the correct type and quantity.

01 / THE PURPOSE

Connect the order and specimen without error.

In the early process, an ID number was assigned to the order form and a label with the same number was attached to the corresponding specimen. Staff then confirmed that both numbers matched. A mismatch could cause one person’s result to be handled as someone else’s.

The second purpose was to confirm that every test tube required for the ordered tests was present. Different tests require different tubes, and any shortage or excess had to be checked with the medical institution.

02 / THE TRAP

It is simple—so people cannot make mistakes?

At first, one person performed the work. In one meeting, someone said, “It is such a simple task that nobody should make a mistake.” When people in different positions actually tried it, mistakes occurred regardless of experience or status.

This is not a story about laughing at one person. Repetitive work that looks simple is exactly where familiarity and fatigue erode attention. The workplace showed us that “be more careful” was not enough.

03 / DOUBLE CHECK

One person reads. One person picks.

To improve accuracy, we changed verification to a two-person task. One person watched the screen and read the patient and required tube information aloud. The other removed the matching tubes from the specimen rack.

Two sets of eyes and ears improved accuracy, but one process now required two people.

04 / NEXT QUESTION

Could one person do it without sacrificing accuracy?

“Accuracy first, speed second, low cost third.” We wanted to return a two-person task to one person without returning responsibility to human attention alone. The answer was not at a clinical-laboratory exhibition. It was at a logistics show I happened to visit.

Before removing a person,
separate the roles people are performing.