Table 1
Characteristics of patients eligible and ineligible for diagnostic model development data.
| Diagnostic model cases | Excluded cases | |
|---|---|---|
| n = 395 | n = 214 | |
| Age (years), mean (sd) | 49.8 (13.9) | 50.9 (13.9) |
| Age Categories | ||
| 18–34 years 35–44 years 45–54 years 55–64 years 65+ years | 64 (16.2) 82 (20.8) 102 (25.8) 93 (23.5) 54 (13.7) | 27 (12.6) 54 (25.2) 50 (23.4) 45 (21.0) 38 (17.8) |
| Gender: Female | 237 (60.0) | 146 (68.2) |
| BMI category: obese a | 160 (40.5) | 88 (41.1) |
| Self-certified time off work or given sick note due to current episode b | 99 (40.9) | 45 (37.2) |
| Back pain intensity [33], mean (sd) c | 5.5 (2.2) | 5.7 (2.1) |
| Leg pain intensity [33], mean (sd) c | 5.3 (2.4) | 5.1 (2.4) |
| RMDQ disability score (0–23) [34], mean (sd) d | 12.8 (5.7) | 12.4 (5.8) |
| Duration of back symptoms | ||
| Less than 6 weeks 6–12 weeks >3 months | 132 (33.6) 94 (23.9) 167 (42.5) | 86 (40.1) 32 (15.0) 96 (44.9) |
| Duration of leg symptoms | ||
| Less than 6 weeks 6–12 weeks >3 months | 165 (43.9) 85 (22.6) 126 (33.5) | 86 (41.5) 35 (16.9) 86 (41.6) |
| General Health: Fair/poor | 143 (36.3) | 79 (36.9) |
| Two or more other health problems e | 43 (10.9) | 37 (17.3) |
| Positive cough/sneeze | 102 (25.8) | 27 (12.6) |
| Below knee pain | 278 (70.4) | 152 (71.0) |
| Leg pain worse than back pain | 198 (50.1) | 82 (38.3) |
| Subjective sensory changes in leg | 243 (61.5) | 139 (65.0) |
| Neurological tests deficit (any positive test) Myotomes Dermatomes Reflexes | 228 (57.7) 81 (20.5) 173 (43.8) 91 (23.0) | 99 (46.3) 24 (11.2) 80 (37.4) 28 (13.3) |
| Neural tension tests (any positive test) Straight leg raise (SLR) Crossed SLR Slump Femoral nerve stretch | 240 (60.8) 221 (55.9) 21 (5.3) 64 (16.2) 27 (6.8) | 95 (44.4) 76 (35.5) 1 (0.5) 20 (9.3) 14 (6.5) |
| Positive MRI findings for nerve root compression | 231 (58.5) | 66 (30.8) |
| Clinical diagnosis; Stenosis | 34 (8.6) | 14 (6.5) |
sd, standard deviation;
BMI, body mass index;
RMDQ, Roland Morris Disability Questionnaire;
MRI, magnetic resonance imaging.
All figures are frequencies (percentages) unless stated otherwise as mean (sd).
a BMI obese category = 30 to 40+ kg/m2
b Applicable to only those working n = 365
c Pain intensity measured using the mean of three 0 to 10 numerical rating scales for least and usual back pain over the previous 2 weeks and current back pain intensity
d Roland Morris Disability Questionnaire leg pain version with scores from 0–23 with higher scores indicating higher disability
e The comorbidity health problems included chest problems, heart problems, raised blood pressure, diabetes, circulation problems in the legs