Has there been any research into the sleep measurement of the Philips Health Watch?

Yes, the sleep algorithms used in the Philips Health Watch have been validated for a research version of the Health Watch. This research is currently in the process of being prepared for publication. More information can be found here. (http://incenter.medical.philips.com/doclib/enc/12916038/WeST_relevant_Philips_publications.pdf%3ffunc%3ddoc.Fetch%26nodeid%3d12916038) Please note that the sleep module algorithms are not suitable for people with sleep apnoea or insomnia.