Methods
Design
Data were obtained through a randomized clinical trial
looking for the dose effect of spinal manipulative therapy
for cLBP [3, 6]. Four hundred participants were randomized
to 4 dose groups, 100 patients per group. Participants
were treated 3 times per week for 6 weeks. They
received 0, 1, 2, or 3 SMT sessions per week (0, 6, 12, or
18 total SMT visits) with control visits, consisting of
light massage, on non-manipulation visits. All care was
provided in the Portland metro area. Outcomes were
collected at baseline and 6, 12, 18, 24, 39, and 52 weeks
after randomization on. Randomization coincided with
the first treatment visit.