Recruitment ads were placed in social network websites stating basic inclusion criteria and study details. Interested persons were initially interviewed via phone to rule out major exclusion criteria (e.g. age, general health, and sleep patterns). Persons who were eligible and interested in participating were invited to the sleep laboratory at Assuta Medical Center (Tel Aviva, Israel) for in-lab screening. At the screening visit, all participants signed informed of consent and filled out intake questionnaires, including demographic and health questionnaires, PSQI, and the Horne-Ostberg questionnaire). Participants then received an actigraph for one week to assess the quality and quantity of their sleep and sleep wake patterns and schedules.