Fig. 2From: Association of wood use in bedrooms with comfort and sleep among workers in Japan: a cross-sectional analysis of the SLeep Epidemiology Project at the University of Tsukuba (SLEPT) studyProportion of poor sleep conditions according to the amount of wood in bedrooms. a Proportion of participants with poor sleep quality (PSQI ≥ 6) according to the amount of wood in the bedroom. b Proportion of participants with suspicion of insomnia (AIS ≥ 6) according to the amount of wood in the bedroom. c Proportion of participants with low sleep efficiency (< 70% by actigraphy) according to the amount of wood in the bedroomBack to article page