154 patients over the age of 18 years presenting with mechanically producible low back pain were randomized to receive an early treatment with spinal manipulation, using either a thrust or non-thrust technique, to compare these two methods in terms of pain and disability. Results at discharge from physiotherapist care indicated that, although both significantly improved at all time points, there was no significant difference in pain and disability at discharge between the two groups. Furthermore, it was found that personal equipoise of the treating physiotherapist had a significant influence on both pain and disability. Lastly, there was no significant difference between groups in rate of recovery, total visits, days in care, or the patient's beliefs about avoiding activity.