RDW

MeasuredUseful

How much your red blood cells vary in size.

A wide spread can be the earliest sign of developing iron or B12 deficiency.

Calculated from this result

Once a lab has this measurement, these lines cost it nothing to add.

Part of

How we rate it: Useful

Worth doing for a specific reason: a risk factor, a symptom, an age group.

This rating and the description above were written against published screening guidelines by someone who is not a clinician, and are awaiting review by one. We would rather say that than imply an authority we do not have.

Check-ups that include it

In 80 of the 93 check-ups we track, 86%. Cheapest first.

and 68 more.

Also sold as

Every one of these names refers to this same test. Resolving them to one canonical entry is what makes an honest comparison possible.

  • rdw
  • rdw cv
  • red cell distribution wid
  • red cell distribution width
  • red cell distribution width cv

Information here is for comparing packages, not for diagnosing yourself. Talk to a doctor about which tests you actually need.