Skip to main content

Table 1 Comparison of distribution of baseline variables between groups

From: Predicting a clinically important outcome in patients with low back pain following McKenzie therapy or spinal manipulation: a stratified analysis in a randomized controlled trial

  McKenzie group Manipulation group   
  Number of patients % Total Number of patients % Total RR (95% CI) P-value
Age         
Below 40 107 61.6% 175 117 66.9% 175 0.91 (0.78-1.07) 0.27
Gender         
 Male 72 41.1% 175 83 47.4% 175 0.87 (0.69-1.10) 0.24
Duration of symptoms         
 More than a year 55 31.4% 175 54 30.9% 175 1.01 (0.88-1.16) 0.91
Disability         
 Mild/moderate¤ 64 36.6% 175 68 38.9% 175 0.94 (0.72-1.23) 0.66
Leg pain¤¤         
 Moderate/severe 92 52.6% 175 87 49.7% 175 1.06 (0.85-1.32) 0.59
Back pain¤¤         
 Mild 19 10.9% 175 24 13.7% 175 0.79 (0.45-1.39) 0.42
Sickleave past year         
 Six days or less¤¤¤ 85 52.1% 163 87 52.7% 165 0.99 (0.80-1.20) 0.92
Nerve root involvement         
 Yes* 18 10.3% 175 16 9.1% 175 1.13 (0.59-3.13) 0.72
Pain below the knee         
 Yes 88 50.3% 175 102 58.3% 175 0.86 (0.71-1.05) 0.13
Expectations to recovery         
 High** 84 52.5% 160 68 49.3% 138 1.07 (0.85-1.33) 0.58
Expectations to work         
 High*** 63 37.1% 170 76 43.9% 173 0.84 (0.65-1.09) 0.20
Pain response         
 Centralization§ 151 86.3% 175 156 89.1% 175 0.97 (0.89-1.05) 0.42
  1. N = 350 except Sick leave past year (N = 328), Expectations to recovery (N = 298) and Expectations to work (N = 343).
  2. RR = Relative Risks (95% confidence intervals) show the chance of having the characteristics in the McKenzie group compared to the Manipulation group (i.e. the chance of having pain below the knee in the McKenzie group compared to the Manipulation group).
  3. ¤The total score on Roland Morris were divided into mild (0-5), moderate (6-11), or severe (12-23) disability.
  4. ¤¤Each of the back and leg pain questionnaires included 3 separate 11 point box scales (0-30) comprising the following items: pain at the moment, the worst pain within the past two weeks, and the average level of pain within the last two weeks. For each questionnaires, these summed to a total score ranging from 0 points (no back or leg pain at all) to 30 points (worst possible back or leg pain). The total score was divided into mild (0-10), moderate (11-20), or severe (21-30) pain.
  5. ¤¤¤Number of days reported by the patient. Dichotomized into high/low risk groups according to scores above/below the median of 6 found in the sample.
  6. *Based on presence of dominant leg pain in any distribution as well as the following clinical signs of nerve root pain: positive straight leg raise test of less than 60 degrees that reproduced leg pain in combination with diminished reflexes, and/or muscle weakness in a myotomal or dermatomal pattern, and/or sensory disturbances.
  7. **Scored before the initiation of third treatment on an 11-point box scale. 0 indicates I expect no improvement at all; 10, I am certain that I will improve. Dichotomized into high/low risk groups according to the median scores: high (8 or above), low (below 8).
  8. ***Measured on an 11 point box scale regarding expectations about coping with work tasks in six weeks time (endpoints ‘No trouble at all’ and ‘So much trouble that I won’t be able to do my job at all’). Dichotomized into high/low risk groups according to the median scores low (3 or above); high (below 3).
  9. §Movement of symptoms from a distal to a more proximal location during pre-randomization physical screening.