Here is the design of a clinical trial:

Official Title: Use of Financial Incentives to Increase Live Kidney Donor Follow-up Compliance

Included conditions:
- Living Donors
- Nephrectomy
- Kidney

Study Armgroups:
- {'label': 'Standard of Care', 'type': 'NO_INTERVENTION', 'description': 'Participants in the control arm will be instructed to attend required follow-up as is standard of care, but will not receive a financial incentive.'}
- {'label': 'Financial Incentive', 'type': 'EXPERIMENTAL', 'description': 'Up to three gift cards to a major online retailer will be mailed to participants assigned to the intervention arm after complete (i.e. all components addressed) and timely (i.e. within the policy-defined follow-up period) submission of follow-up data at each 6-month, 1-year, and 2-year follow-up visit.', 'interventionNames': ['Other: Financial Incentive']}

Interventions:
- {'type': 'OTHER', 'name': 'Financial Incentive', 'description': 'Up to three gift cards to a major online retailer.', 'armGroupLabels': ['Financial Incentive'], 'otherNames': ['Behavioral']}

Primary Outcomes:
- {'measure': 'Patient Compliance with Follow-Up', 'description': 'Rate of policy-defined complete (all components addressed) and timely (within 60 days before or after the 6-month, 1-year, or 2-year post donation date; i.e. 120-day period) submission of data at 6-month, 1-year, and 2-year follow-up visits (assessed separately for each follow-up time point and as a composite outcome over the study period).', 'timeFrame': '2 years'}

Please estimate the sample size based on the assumption: 
The study is designed to have 80% power to detect a difference if the follow-up rate in the intervention group is 83%, and 90% power if the follow-up rate is 85%.
Sample size calculation
          The total sample size for this study (including participants at both MDJH and MDUM) is Nâ=â320. With 160 participants in each arm given the hypothesized follow-up in control group of 70%, we will have 80% power to detect a difference between the study arms if the follow-up rate is 83% in the intervention group, and 90% power to detect a difference between study arms if follow-up in intervention group is 85% (Fig.Â 2). The hypothesized follow-up in the control group is derived from historical follow-up percentages at MDJH and MDUM.
Fig. 2Power calculation of evaluating the effectiveness of the financial incentive intervention with 320 donors enrolled at MDJH and MDUM over 4âyears