Sleep disturbances predict future sickness absence among individuals with lower back or neck-shoulder pain: a 5-year prospective study.

Aili K, Nyman T, Hillert L, Svartengren M.

Scand J Public Health. 2015 May;43(3):315-23. doi: 10.1177/1403494814567755. Epub 2015 Feb 27.

PMID: 25724467