Secondary outcome measures include a visual analogue scale (VAS) to back pain intensity during the latest week. This was presented with a single line and scoring range from 0 for no pain to 100 mm for unbearable pain was used
Secondary outcomemeasures include a visual analogue scale (VAS) to back painintensity during the latest week. This was presented with a singleline and scoring range from 0 for no pain to 100 mm for unbearablepain was used