Study design
Participants were randomly assigned to yoga and waitlist control groups using a computer-generated random number sequence. Randomization was carried out as follows. Participants were given numbers from 1 to 62 which were not dependent on their names, the order in which they were enrolled, or any other factor. Sixty-two random numbers were generated using specific software. In a separate column adjacent to the serial numbers of the participants, all the random numbers were written. Identical-sized pieces of paper were used to write the random numbers. They were folded identically and mixed. The slips of paper were placed alternately in 2 boxes (labeled as Box ‘A’ and Box ‘B’) by a person who was unaware of the trial. Individuals allotted to Group ‘A’ were given the yoga intervention while individuals in group ‘B’ were assigned to the waitlist control group. In 22 of the 62 participants we were unable to collect data on visual analog scales for pain, sit and reach for spinal flexibil- ity, and STAI-S because after the MRI scan they returned to their homes. Their next visit was for the yoga intervention (yoga group) or health education (control group). Hence, the data of 40 participants randomized to yoga and control groups is presented. Accordingly, Table 2 (MRI data) presents data on these 40 patients. Figure 1 is the Trial Profile, which mentions the number of participants in yoga and control groups at dif- ferent stages. Hence, both groups were allocated 20 partici- pants each and in this way the study design is a parallel group design with an allocation ratio of 1:1. Recruitment of the participants was done in June 2011 and post-intervention assess- ments were completed in October 2011.
A record was kept of participant medication intake. Participants took NSAID (non-steroidal anti-inflammatory drugs) or analgesics when they felt the need. This was recorded.