Here is the design of a clinical trial:

Official Title: Serious Game-based Intervention in Gait Rehabilitation for Children With Cerebral Palsy: Randomized Control Trial

Included conditions:
- Cerebral Palsy
- Gait Disorders, Neurologic

Study Armgroups:
- {'label': 'Control group', 'type': 'ACTIVE_COMPARATOR', 'description': 'Classic rehab (physio including strength rehab, fitness, motor activity...) + treadmill gait training 3\\*/week/4weeks:\n\n5 minutes of warm-up with gradual increase in treadmill speed, max 20 minutes of walking at 80% of maximum speed, 5 minutes of active recovery with gradual decrease in treadmill speed.\n\n(protocol from Grecco et al.)', 'interventionNames': ['Other: Treadmill']}
- {'label': 'Test group', 'type': 'EXPERIMENTAL', 'description': 'Classic rehab - same as control group - (physio including strength rehab, fitness, motor activity...) + overground ARROW CP gait training 3\\*/week/4weeks:\n\nwalking sprint session at maximal speed with gradual increase in number of repetitions over the weeks.\n\n(protocol from Verschuren et al.)', 'interventionNames': ['Other: Serious game ARROW CP']}

Interventions:
- {'type': 'OTHER', 'name': 'Serious game ARROW CP', 'description': 'ARROW CP is developed for Microsoft Hololens headset. Feedback on gait performance are delivering to the participant in real time and with delay. Participants have to walk at their maximal speed during "sprint session".', 'armGroupLabels': ['Test group']}
- {'type': 'OTHER', 'name': 'Treadmill', 'description': 'Participant walk on a treadmill at 80% of their maximal speed during maximum 20 minutes (+5 min warm-up / 5 min cool-down)', 'armGroupLabels': ['Control group']}

Primary Outcomes:
- {'measure': '6 minutes walking test', 'description': 'Aim of the measurement: To quantify changes in the parameters of walking quality (speed, cadence, step length).\n\nProcedure: The patient is instructed to walk for 6 minutes in an unobstructed corridor. The distance walked is recorded for the calculation of walking speed. Fatigue is assessed with a Borg scale and heart rate is continuously recorded.', 'timeFrame': '6 minutes'}

Please estimate the sample size based on the assumption: 
Alpha=0.05, beta=0.20 (power=0.80), and a failure rate of 10%. Statistical significance level of p=0.05 for ANOVA and other tests. All analyses will be performed using R, with the trial statistician blinded to group allocation until the database is locked.
Sample size and statistical analysis
        According to a study of Grecco et al an average augmentation of 83% (range 80%â85%) in 6MWT was calculated after following 12âweeks of TT in postoperative context.13 The distance travelled during the 6MWT increases from before: 166.4Â±39.1âm to after: 304.7Â±75.8âm. The effect size was calculated: d=2.29. In this previous study, the mean number of training sessions throughout the 12-week period was 11.1 (around 1 session per week) that is, total dose of 6âhours/12âweeks. It has been hypothesised that participants following a more intensive protocol (three sessions/week that is, total dose of 6âhours/4âweeks) will show the same effect on the 6MWT.
        With an alpha=0.05âand beta=0.20 (power=0.80), a sample size of 6 subjects per group will be required. When taking a failure rate of 10% into account, 14 subjects should be included.
        The required sample size was calculated with G Power 3.1.9.7. Parameter was t-tests â Means; difference between two independent means (two groups) with a priori analysis.
        The effect of the GT protocol will be analysed using a multivariate repeated measures analysis of variance (ANOVA). The possible differences between and within T0, T1 and T2 for the intervention group and control group will be calculated with a statistical significance level of p=0.05. If there is a significant difference, a post hoc test will be executed to further investigate group differences. Quantitative descriptive statistics will be used to present patient characteristics and global results. Data from PACES questionnaire will be analysed using normality test (deciding to use parametric/non-parametric statistics), descriptive statistics, reliability test (Cronbach Alpha/composite reliability), Pearson/Spearman correlational test. All statistical analyses will be performed using R with a statistical significance level of p=0.05. Moreover, the trial statistician will remain blinded to group allocation until the database has been locked.