Stefan Elbers

40 Chapter 2 Table 1. Continued. Author (year) cohort N Dropout (%) Lost to follow- up (%) Nationality % Females Mean age ( SD ) Patient group Mean pain duration (months) Mangels (2009): a 363 0 6.19 Germany 78.8 49.5 (9) musculoskeletal pain NA Mangels (2009): b 363 0 6.72 Germany 75.6 48.3 (15.8) musculoskeletal pain NA Martín (2012) 180 10 13.89 Spain 93.46 49.07 (8.92) fibromyalgia 174.22 McAllister (2005) 276 20.65 54.79 United States 66.3 44.7 (9.7) chronic non- malignant pain NA Meng (2011) 382 11.17 16 Germarny 65.2 50.2 (7.6) chronic low back pain NA Merrick (2009) 255 1.79 -1.21 Sweden 79 39 (NA) disabling chronic pain NA Merrick (2012) 296 NA NA Sweden 76 39.2 (9.7) chronic pain 62.4 Monticone (2013) 90 0 0 Italy 60 48.96 (7.97) chronic non- specific low back pain 22.15 Monticone (2016) 150 1.33 12.16 Italy 62.67 53.2 (11.1) non-specific low back pain 21.7 Nagel (2009) 351 38.96 0 Germany 59.3 44.7 (NA) chronic nonspecific back pain 140.4 Nicholas (2020): a 140 10.61 28.81 Australia 51 42.05 (12.33) chronic pain 67.16 Nicholas (2020): b 140 8.11 41.18 Australia 55 43.22 (11.08) chronic pain 77.71 Olason (2004) 158 24.05 NA Iceland 70.9 39.5 (NA) chronic pain NA Oslund (2009) 108 0 42.5 USA 70.4 55 (11.47) chronic pain 110.44 Persson (2012) 813 13.53 27.6 Sweden 79 40 (9.6) musculoskeletal pain 49.2 Pietilä- Holmner (2020) 467 NA NA Sweden 85.5 43.6 (10.8) musculoskeletal chronic pain NA Reck (2017) 71 NA NA Switzerland 54 43.59 (11.84) chronic non- specific low back pain NA