Fang S, Subramanian S, Piccolo R, et al. Geographic variation in sleep duration: a multilevel analysis from the Boston Area Community Health (BACH) Survey. J Epidemiol Community Health 2015;69:63–9. The second sentence under the heading ‘Neighbourhood variation in sleep duration and Determinants’ has been corrected to read ‘Looking at the ICC, the total variance attributable to between-neighbourhood factors was reduced 20.6% for very short sleep and 26.2% for long sleep’.