Nadal N, de Batlle J, Barbe F, Marsal JR, Sanchez-de-la-Torre A, Tarraubella N, Lavega M, Sanchez-de-la-Torre M. Predictors of CPAP compliance in different clinical settings: primary care versus sleep unit. Sleep Breath. 2018 Mar;22(1):157-63. doi: 10.1007/s11325-017-1549-7
Warttig SL, Forshaw MJ, South J, White AK. New, normative, English-sample data for the Short Form Perceived Stress Scale (PSS-4). J Health Psychol. 2013 Dec;18(12):1617-28. doi: 10.1177/1359105313508346