pilot clinical trial to evaluate the safety and different efficacy of different wavelength of Ellise on chronic non specific low back pain

INTERVENTION: Medical Device : The control group will receive sham invasive laser acupuncture(ILA) for 10 min and real electroacupuncture(50Hz, triangular wave) for 10 min, while 650 nm and 830 nm groups will receive real ILA(i.e., 650ILA group, 650 nm wavelength; 830 ILA group, 830nm wavelength: 20mW, 50Hz)for 10 min and real electroacupuncture(50Hz, triangular wave) at BL23, BL24, BL25, GB30 CONDITION: Diseases of the musculo‐skeletal system and connective tissue PRIMARY OUTCOME: Visual Analogue Scale SECONDARY OUTCOME: European Quality of Life Five Dimension. Five Level Scale Oswestry Disability Index INCLUSION CRITERIA: Participants meeting all of the following criteria will be included in this trial:1) male or female aged 19 to 70 years; 2) experiencing CLBP lasting for at least the previous three months; 3) Scoring = 40 points on a 100‐mm VAS for pain at the time of screening; 4) Korean language fluency that is adequate for reliable completion of all study assessments; and 5) voluntary provision of informed consent.