Thyroid analytes TSH, FT3 and FT4 in serum of healthy elderly subjects as measured by the Roche modular system: do we need age and gender dependent reference levels? - Kußmaul, Till; Greiser, Karin Halina; Haerting, Johannes; Werdan, Karl; Thiery, Joachim; Kratzsch, Jürgen (Clinical laboratory, 2014)