Baseline characteristics of low back pain presentations
| Intervention (n=1392) | Control (n=3233) | |
| Age, years | 53.4 (20.0) | 52.0 (20.3) |
| Female sex | 684 (49.1) | 1602 (49.6) |
| Primary diagnosis | ||
| Non-specific low back pain | 1249 (89.7) | 2909 (90.0) |
| Radicular low back pain | 143 (10.3) | 324 (10.0) |
| Socioeconomic status | ||
| SEIFA deciles 1–5 | 338 (25.6) | 1085 (35.3) |
| SEIFA deciles 6–10 | 980 (74.4) | 1988 (64.7) |
| Day of presentation | ||
| Weekday | 1008 (72.4) | 2316 (71.6) |
| Weekend | 384 (27.6) | 917 (28.4) |
| Hour of presentation | ||
| Working hours | 718 (51.6) | 1718 (53.1) |
| After hours | 674 (48.4) | 1515 (46.9) |
| Mode of arrival | ||
| Self-presented | 946 (68.1) | 2202 (68.1) |
| Ambulance | 434 (31.2) | 1018 (31.5) |
| Other | 10 (0.7) | 13 (0.4) |
| Triage category | ||
| 2 (emergency) | 31 (2.2) | 52 (1.6) |
| 3 (urgent) | 492 (35.3) | 1174 (36.3) |
| 4 (semiurgent) | 849 (61.0) | 1895 (58.6) |
| 5 (non-urgent) | 20 (1.4) | 112 (3.5) |
| Length of emergency stay, hours | 4.0 (2.8) | 4.1 (3.0) |
Data are n (%) or mean (SD).
Data are missing for socioeconomic status (234, 5.1%) and mode of arrival (2, 0.4%).
The primary diagnosis codes were categorised into non-specific back pain and radicular back pain. Lower numbers in socioeconomic status are more disadvantaged while higher numbers are less disadvantaged. Triage categories are based on the Australasian Triage Scale; there were no eligible low back pain presentations in triage category 1 (life-threatening).
SEIFA, Socio-Economic Indexes for Areas.