Here is the design of a clinical trial:

Official Title: for Infection Prevention in Sickle Cell Anemia (ZIPS)

Included conditions:
- Sickle Cell Disease

Study Armgroups:
- {'label': 'Zinc', 'type': 'EXPERIMENTAL', 'description': 'Dietary Supplement: Zinc 10mg dispersible zinc sulfate tablet', 'interventionNames': ['Dietary Supplement: Zinc']}
- {'label': 'Placebo', 'type': 'PLACEBO_COMPARATOR', 'description': 'Dispersible tablet with inert ingredients, identical to zinc in appearance', 'interventionNames': ['Other: Placebo']}

Interventions:
- {'type': 'DIETARY_SUPPLEMENT', 'name': 'Zinc', 'description': '10mg dispersible zinc sulfate tablet', 'armGroupLabels': ['Zinc']}
- {'type': 'OTHER', 'name': 'Placebo', 'description': 'Dispersible tablet with inert ingredients, identical to zinc in appearance', 'armGroupLabels': ['Placebo']}

Primary Outcomes:
- {'measure': 'Incidence of infection', 'description': 'The investigators will assess reduction in incidence of severe or invasive infections, with or without culture or PCR confirmation.', 'timeFrame': '12 months'}

Please estimate the sample size based on the assumption: 
Alpha of 0.025 for a one-sided test or 0.05 for a two-sided test, 80% power, and a 10% loss to follow-up.
Sample size and power calculation
        We will assess reduction in incidence of severe or invasive infections, with or without culture or PCR confirmation. Sample size is based on incidence of severe or invasive infections, using a baseline rate of 0.71 infections/child/year, derived from data of children from the NOHARM study [5]. Power calculations assume an alpha of 0.025 for a one-sided test or 0.05 for a two-sided test. With an incidence of 0.71 severe or invasive infections/year in the placebo group, a sample size of 250 children (with a 10% loss to follow-up) will have 80% power to detect a decrease of â¥â40% in severe or invasive infection incidence over the 12-month study period. This decrease is smaller than the 47â88% reduction in clinical infection incidence in adolescents and adults in previous studies [40â42], so the study sample size should allow us to detect the expected effects of zinc on infection incidence.