Here is the design of a clinical trial:

Official Title: The Facial Nerve Palsy And Cortisone Evaluation (FACE) Study in Children: A Randomized Double-blind, Placebo-controlled, Multicenter Trial

Included conditions:
- Facial Palsy
- Facial Nerve Diseases
- Borrelia Infection of Central Nervous System
- Bell Palsy

Study Armgroups:
- {'label': 'Prednisolone', 'type': 'EXPERIMENTAL', 'description': 'Prednisolone', 'interventionNames': ['Drug: Prednisolone']}
- {'label': 'Placebo', 'type': 'PLACEBO_COMPARATOR', 'description': 'Placebo oral tablet', 'interventionNames': ['Drug: Placebo Oral Tablet']}

Interventions:
- {'type': 'DRUG', 'name': 'Prednisolone', 'description': 'Prednisolone 5 milligram tablets, 1 milligram per kilogram bodyweight per orally per day during 10 days, maximum 50 milligram per day.', 'armGroupLabels': ['Prednisolone'], 'otherNames': ['Batch 18A71, Orifarm Generics A/S']}
- {'type': 'DRUG', 'name': 'Placebo Oral Tablet', 'description': 'Placebo tablets with identical appearance to the experimental drug', 'armGroupLabels': ['Placebo'], 'otherNames': ['Batch 18A61, Orifarm Generics A/S']}

Primary Outcomes:
- {'measure': 'House-Brackmann scale', 'description': 'Total recovery in the two treatment groups measured with the House-Brackmann scale.\n\nThe House-Brackmann scale (I is normal function and VI is total loss of function) is chosen as primary outcome measure since it is an objective instrument, easy to perform and the one most frequently used in previous studies. The time point 12 months for evaluation of total recovery is chosen as no further improvement of the facial nerve function is expected after 12 months.', 'timeFrame': 'At 12 months (+/- 2 weeks) after inclusion'}

Please estimate the sample size based on the assumption: 
The statistical significance level is set at p < 0.05, with a power of 80%. A 10% dropout rate is also assumed.
Sample size estimation and recruitment
        In the FACE study, the sample size is calculated on the primary outcome (i.e. complete recovery, defined as HBGS grade I, at the 12-month follow-up visit). Previous studies have shown spontaneous complete recovery (HBGSâ=âI) to occur in approximately 80% of untreated children with an acute FNP [10â12], this is the estimated percentage for complete recovery in the control group. Furthermore, in accordance with previous studies in adults [18], we consider a clinically important difference between groups to be 10%, hypothesizing the intervention to cause an increase in complete recovery rate from 80 to 90% in the treatment group. To be able to show a 10% difference between groups with statistical significance (pâ<â0.05) and a power of 80% [38], a total of 500 participants (250 in each group), is needed for the trial, allowing 10% of participants to be lost to follow-up.
        In order to promote progress and ensure high quality of study procedures, investigators and study nurses received education in Good Clinical Practice before the study start and attend yearly meetings available to all personnel. Investigators are thoroughly instructed in applying the HBGS and the SFGS for reliable evaluation of facial impairment, and at the 1- and 12-month follow-ups, only one or two investigators per study center will apply the HBGS and the SFGS. Recruitment rate is enhanced by continuous contact between the coordinating investigator, the principal investigators and study nurses at each study center, throughout the study period.