Instead of a blood test, the app developed by researchers at Emory University in the US, uses photos of a person’s fingernails taken on a smartphone to accurately measure how much haemoglobin is in their blood.
A single smartphone image can measure haemoglobin level with an accuracy of 2.4 grammes/decilitre with a sensitivity of up to 97 per cent, researchers said.
“All other ‘point-of-care’ anaemia detection tools require external equipment, and represent trade-offs between invasiveness, cost, and accuracy,” said Wilbur Lam, principal investigator of the study appearing in the journal Nature Communications.
The app facilitates self-management by patients with chronic anaemia, allowing them to monitor their disease and identify therapy and transfusion patterns with no need to draw blood.
This could possibly reduce the side effects or complications of having transfusions too early or too late. The researchers said that the app should be used for screening, not clinical diagnosis.
The technology could be used by anyone at any time, and could be especially appropriate for pregnant women, women with abnormal menstrual bleeding, or athletes.
The use of fingernail beds, which do not contain melanin, means the test can be valid for people with a variety of skin tones.