Study objectives Clinical and population health recommendations are derived from studies
that include self-report. Differences in question wording and response scales may …

Introduction Self-reported habitual sleep duration has been used widely in epidemiologic
research, yet this measure remains to be validated. We evaluated whether simple sleep …

A recent epidemiology study [1] contains the latest in a long series of U-shaped relationships
[2–5] linking a health problem with self-reported sleep duration: the outcome of interest (in …

There is no standard way to ask about sleep duration in surveys, and little is known about
the comparability of different questions. This article reports on a randomized survey …

Epidemiological studies on sleep often use questionnaires, and measurement of validity
provides necessary guidance in selection of valid single sleep questions. Twenty-five items …

Background: Recent epidemiologic studies have found that self-reported duration of sleep is
associated with obesity, diabetes, hypertension, and mortality. The extent to which self …

Objective Although the problems associated with insufficient sleep have been thoroughly
researched, there has been far less substantiation of problems associated with long sleep …

Abstract Study Objectives Most epidemiological studies assess sleep duration using
questionnaires. Interpreting this information requires understanding the extent to which self …

Objectives This study sought to evaluate how sleep difficulties have changed over time and
to evaluate if these changes relate to changes in sleep duration. Design National Health …

Abstract Study Objective: The trend in sleep duration in the United States population
remains uncertain. Our objective was to examine changes in sleep duration from 1985 to …