Fig. 2

Group-wise display of calculated serum osmolality on admission according to presence or absence of mild (Na < 135 mmol/L, Na ≥ 130 mmol/L) or moderate-to-severe (Na < 130 mmol/L) hyponatremia. The following formula was used: serum osmolality = 2x Na (mmol/L) + Urea (mmol/L) + Glucose (mmol/L). Numbers indicate the available calculated results per group