Actimetry in sleep medicine.

Actigraphy is more and more used in the longterm record of sleep of patients with insomnia. The correlation with data from polysomnography is reasonable for parameters like total sleep period (TSP) with r = 0,95-0,97 in healthy controls and r = 0,77-0,91 in patients. However for parameters, which inform about sleep fragmentation like wake after sleep onset (WASO) the correlation is not satisfieing with r = 0,87 in healthy controls and r = 0,49-0,63 in patients with fragmented sleep. The question is therefore, if actigraphs are really more useful in the record of sleep in patients with insomnia and fragmented sleep than sleep calenders.