The primary difference lies in the measurement markings:
Tear Flow Test Strips (PO-5400) include a printed metric scale directly on each strip, allowing for quick, unmistakable interpretation without additional tools
Schirmer Tear Test Strips (PO-6394) do not include printed measurements, so a separate metric ruler is required during testing
Both types are used to assess tear production, but the printed metric scale on the Amcon version may assist clinical efficiency.