Figure 4

Importance of timing treatment: Phase shift (ΔΦ) of circadian rhythm in urinary chloride excretion as a function of timing of prolonged corticosteroid therapy in children with severe asthma. Drastic differences in direction and extent of drug-induced shift of a circadian acrophase as a function of medication timing. The reference phase (0°) is the phase of urinary chloride excretion of a group of children with moderate asthma not treated by corticosteroid. Vertical 95% confidence intervals indicate detection of statistically significant circadian rhythm (by cosinor) [15].