Smartphone app for non-invasive detection of anemia using only patient-sourced photos

TLDR

Anemia, affecting over 2 billion people, is defined by low hemoglobin levels. The study proposes a non‑invasive, on‑demand diagnostic approach using a smartphone app and photos to replace traditional blood tests. The app estimates hemoglobin by analyzing fingernail bed photo color and metadata, achieving ±2.4 g dL⁻¹ accuracy and 97 % sensitivity versus CBC in 100 subjects. In 100 subjects, the app achieved ±2.4 g dL⁻¹ accuracy and 97 % sensitivity, and with personalized calibration it reached ±0.92 g dL⁻¹ accuracy in 16 patients, enabling instant, remote anemia detection via smartphone.

Abstract

Abstract We introduce a paradigm of completely non-invasive, on-demand diagnostics that may replace common blood-based laboratory tests using only a smartphone app and photos. We initially targeted anemia, a blood condition characterized by low blood hemoglobin levels that afflicts >2 billion people. Our app estimates hemoglobin levels by analyzing color and metadata of fingernail bed smartphone photos and detects anemia (hemoglobin levels <12.5 g dL −1 ) with an accuracy of ±2.4 g dL −1 and a sensitivity of 97% (95% CI, 89–100%) when compared with CBC hemoglobin levels ( n = 100 subjects), indicating its viability to serve as a non-invasive anemia screening tool. Moreover, with personalized calibration, this system achieves an accuracy of ±0.92 g dL −1 of CBC hemoglobin levels ( n = 16), empowering chronic anemia patients to serially monitor their hemoglobin levels instantaneously and remotely. Our on-demand system enables anyone with a smartphone to download an app and immediately detect anemia anywhere and anytime.