• Digital and clinical refractometers are valid instruments for the measure of hydration status.

      Niemann, AJ; Yeargin SW; Eberman LE; Mata HM; Adams HA; Dziedzicki DJ (2012-05-21)
      Although some instruments have been validated for clinical measure of hydration status, new and currently invalid instruments are available for purchase and clinical use. Athletic trainers commonly use these instruments to assess hydration status for weight checks and body mass loss charts due to their ease of use. However, the validity of these popular instruments has not yet been established.