Williams V, Qin S, Romano CD, Lewis S, Williams N, Yarr S, Juul KV, Andersson FL. Psychometric evaluation of the Nocturia Sleep Quality Scale based on data from a prospective observational study. J Clin Sleep Med. 2021 Apr 1;17(4):691-701. doi: 10.5664/jcsm.9010
Luciano JV, Barrada JR, Aguado J, Osma J, García-Campayo J. Bifactor analysis and construct validity of the HADS: a cross-sectional and longitudinal study in fibromyalgia patients. Psychological Assessment. 2014 Jun;26(2):395-406.