Pitting Oedema Scale: Grading Peripheral Oedema

The examiner applies firm thumb pressure over a bony prominence, most often the medial malleolus, the dorsum of the foot or the tibia, holds it for around five seconds and observes the indentation left behind. Grading combines two observations: how deep the pit is, and how long it takes to rebound. The most common scheme runs 1+ for a slight pit that rebounds immediately through to 4+ for a deep pit that persists for several minutes.

It is worth being clear about what this scale is and is not. It is a structured description of a physical sign, not a validated psychometric instrument, and no single scheme is universally agreed. Published versions differ in both the depth thresholds and the rebound times they assign to each grade, so a grade recorded without naming the scheme is ambiguous.