When it comes to objectively comparing sleep quality, elderly men don’t catch as many z’s as women, according to a new study that compares subjective reporting to objective sleep measurements.

Nearly 1,000 older people aged between 59 to 79 years participated in the study, which compared an individual’s subjective reports of sleep quality and duration as recorded in a sleep journal to objective data collected by an actigraph, which collects measurements of certain sleep parameters. Women typically reported getting less and poorer quality sleep than men did. Subjective reports indicated it took women 10 minutes longer to fall asleep than men, and total sleep time was more than 13 minutes shorter than men’s. Sleep efficiency was reported to be 4.2% lower than men’s, as well.

When it came time to look at the objective records, however, the results were clearly different. On average, women slept 16 minutes longer than men, and had less fragmented sleep. One reason for the discrepancy could be that men often overestimate their sleep, suggest researchers from Erasmus Medical Center in Rotterdam, Netherlands. The results could also indicate that older women need more sleep time than older men. The full study appears in the Oct 1. issue of the journal Sleep.