2.5. Randomization and Blinding
dorsolumbar pain, pain
Computer-based randomization stratified by age, gender and pain location (neck pain vs. dorsolumbar pain) was performed. All patients, as well as the physician performing the physical examination, were blinded and randomly divided into three groups. The first group of patients (“therapy”) received a supra-threshold electrotherapy with alternating current application, consisting of high-frequency stimulation at 100 Hz and low-frequency stimulation at 2 Hz, which is used in daily clinics [