In 1935, Armand J. Quick and colleagues developed the prothrombin time test. The test measured the extrinsic and common pathways of coagulation. It later became essential for identifying vitamin K effects and monitoring warfarin therapy safely.

The development of the prothrombin time test in 1935 transformed medical understanding of blood clotting, representing a shift towards quantifiable health metrics. In literary culture, this innovation reflects the modern medical world, shaping poetry that grapples with themes of survival, risk, and the fragility of life.