Here is the design of a clinical trial:

Official Title: Adjuvant Laser Meridian Massage in Heroin Addicts With Methadone Treatment: an Observational Case-controlled Study

Included conditions:
- Heroin Dependence

Study Armgroups:
- {'label': 'Laser meridian massage', 'type': 'EXPERIMENTAL', 'description': 'They are treated with laser meridian massage on the back including Bladder meridian and Governor vessel three times a week for 4 weeks.', 'interventionNames': ['Device: laser meridian massage']}
- {'label': 'Control', 'type': 'NO_INTERVENTION', 'description': 'A control group of participants without laser meridian massage treatment are matched by age.'}

Interventions:
- {'type': 'DEVICE', 'name': 'laser meridian massage', 'description': 'The participants will undergo 12 sessions of laser meridian massage, thrice a week, for 4 weeks, using a gallium aluminum arsenide LaserPen (maximal power, 150 mW; wavelength, 810nm; area of probe, 0.5cm\\^2; power density, 300mW/cm\\^2; pulsed wave; RJ-Laser, Reimers \\& Janssen GmbH, Waldkirch, Germany). The laser treatment will be applied to the back including Bladder meridian (BL11-25) and Governor vessel (GV3-14) for 15 minutes, to deliver a total treatment dose of 67.5J/cm\\^2.', 'armGroupLabels': ['Laser meridian massage']}

Primary Outcomes:
- {'measure': 'Heroin use', 'description': 'Times or days of heroin use during last week', 'timeFrame': '2 weeks of treatment'}
- {'measure': 'Heroin use', 'description': 'Times or days of heroin use during last week', 'timeFrame': '4 weeks of treatment'}
- {'measure': 'Urine morphine', 'description': 'Obtainurinary morphine concentration', 'timeFrame': '2 weeks of treatment'}
- {'measure': 'Urine morphine', 'description': 'Obtain urinary morphine concentration', 'timeFrame': '4 weeks of treatment'}

Please estimate the sample size based on the assumption: 
significance level (α) of 0.05, desired power (1−β) of 0.80, 7% dropout rate
2.4
        Sample size
        A sample size of 28 was calculated to be needed based on 2-way repeated-measures analysis of variance with a medium effect size of 0.25, a significance level (Î±) of 0.05, and a desired power (1âÎ²) of 0.80.[13] Anticipating a 7% dropout rate, a total of 30 study participants will need to be recruited.