Fig. 4From: Implications of standardization of serum 25-hydroxyvitamin D data for the evaluation of vitamin D status in Germany, including a temporal analysisWeighted relative frequency for original and standardized serum 25(OH)D of GNHIES98 samples. 25(OH)D, Serum 25-hydroxyvitamin D; GNHIES98, German National Health Interview and Examination Survey 1998Back to article page