2.2. Participants and study size
In this study, we enrolled patients diagnosed with chronic NSLBP from April 2020 to April 2021. Our sample size calculation was based on the detection of a 1.5-point difference in VAS score post treatment between the single and combined interventions. We estimated the mean and standard deviation of the single intervention group from a previously published studyCharacteristics of subjects in each group.EA = electroacupuncture, LP = lumbar-pelvic training, SD = standard deviation.Flow diagram of participants.