Here is the design of a clinical trial:

Official Title: Leveraging Community-based Platforms to Improve Access and Adherence to PrEP for Young Women in South Africa

Included conditions:
- PrEP
- HIV Prevention
- Adolescence
- Cost-effectiveness

Study Armgroups:
- {'label': 'Health Club', 'type': 'EXPERIMENTAL', 'description': 'A group-based community health club akin to an ART adherence club', 'interventionNames': ['Behavioral: Group-based Community Health Club']}
- {'label': 'One-on-one', 'type': 'EXPERIMENTAL', 'description': 'One-on-one adherence counselling and support', 'interventionNames': ['Behavioral: Individual-based Adherence Support']}
- {'label': 'Medication pick-up', 'type': 'NO_INTERVENTION', 'description': 'Community-based medication dispensary'}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'Group-based Community Health Club', 'description': 'GBHCs will be facilitated by trained Lay Health Counsellors (LHC). GBHCs will consist of a maximum 20 participants. GBHC sessions will held multiple times a month in each study area, allowing for flexibility for study participants. Sessions will be held at a safe and secure, centrally located area within the study community, and will be regularly monitored and assessed by the study coordinator. Participants will be invited to join a club-specific WhatsApp group to facilitate group communication and adherence support throughout the month. They will also be invited to partner up with another participant to provide mutual peer support. Permission will be sought from group-based adherence support participants before they are added to WhatsApp groups. Group adherence counsellors assigned will be members of WhatsApp groups, and will monitor all shared content to ensure that no inappropriate content or private information is shared in the group.', 'armGroupLabels': ['Health Club']}
- {'type': 'BEHAVIORAL', 'name': 'Individual-based Adherence Support', 'description': 'IAS participants will be matched to a LHC and will schedule IAS sessions once-a-month for the duration of the study. These sessions will be held at a centralized location within the study community. The sessions will be semi-structured to allow for participant-driven discussion of any adherence challenges and key-messages. The adherence curriculum will also explore motivations for PrEP and adherence and focus on practical adherence tips, environmental cues, integration of PrEP within daily routines, short-term goal-setting, problem-solving, safe PrEP disclosure and social support, risk reduction counselling, partner communication, and HIV risk perception. A subset of IAS sessions will be audio-recorded for quality assurance by investigators and the study coordinator. These recordings are for training purposes only and will not form part of the dataset. Consent for recording IAS sessions will be sought from participants during the pre-enrolment consent process.', 'armGroupLabels': ['One-on-one']}

Primary Outcomes:
- {'measure': 'The cost per adolescent girl and young women on pre-exposure prophylaxis', 'description': 'Itemized cost menus', 'timeFrame': '10 months'}
- {'measure': 'The incremental cost-effectiveness ratio per incidence HIV case averted', 'description': 'Dynamic infectious disease model of HIV', 'timeFrame': '10 months'}

Please estimate the sample size based on the assumption: 
80% power, alpha of 0.05, chi-square test for independence with two degrees of freedom, and an attrition rate of 10%.
Sample size and power calculations
        A sample size was calculated to have 80% power to detect differences in the proportion of participants adhering to PrEP among the three study arms (Aim 2) using the chi-square test for independence with two degrees of freedom, with an alpha of 0.05, and assuming an attrition rate of 10% for those who (1) withdraw voluntarily from the study, (2) initiate on PrEP but withdraw due to adverse events (e.g. hepatic or renal abnormalities), or (3) become ineligible for PrEP (e.g. seroconvert). The effect size estimate was informed by prior experience from the field, where an effect size of 0.30 has been found between ART clients receiving some adherence support and those receiving none. However, we use a more conservative effect size of 0.15, to account for the fact that adherence support may not lead to the same gains in adherence among HIV-negative PrEP clients as it does with HIV-positive ART clients. The sample size was calculated to be 160 per arm (480 total).