Here is the design of a clinical trial:

Official Title: PROMPT to Improve Speech Motor Abilities in Children With Cerebral Palsy

Included conditions:
- Cerebral Palsy
- Dysarthria

Study Armgroups:
- {'label': 'PROMPT Treated', 'type': 'EXPERIMENTAL', 'description': 'PROMPT treatment, twice a day, for 5 days a week, for 3 consecutive weeks', 'interventionNames': ['Behavioral: PROMPT']}
- {'label': 'Control', 'type': 'NO_INTERVENTION', 'description': 'Usual treatment'}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'PROMPT', 'description': "PROMPT treatment is consistent with the principles of motor learning, in that every session includes a blocked pre-practice followed by variable and distributed practice and a gradual, hierarchical increase of complexity. Speech motor goals are integrated in goals for language and functional communication. During a PROMPT session tactile-kinesthetic-proprioceptive inputs are consistently provided, in order to shape speech movements, to give information on sequencing and timing and to introduce constraints for the reduction of degrees of freedom at the articulators' level in favour of motor control.", 'armGroupLabels': ['PROMPT Treated'], 'otherNames': ['motor speech treatment']}

Primary Outcomes:
- {'measure': 'Verbal Motor Production Assessment for Children (VMPAC)', 'description': 'Standardized motor speech assessment, which includes 5 subscales, where higher scores mean better performance: Global motor control (range 20-0); Focal oromotor control (range 268-0); Sequencing (range 46-0); Connected speech and language (range 45-0); Speech Characteristics (range 7-0)', 'timeFrame': 'after the end of treatment period (4 weeks from baseline)'}
- {'measure': 'Phonetic Inventory', 'description': 'motor speech measure', 'timeFrame': 'after the end of treatment period (4 weeks from baseline)'}
- {'measure': 'the Intelligibility in Context Scale - Italian version', 'description': 'motor speech measure, range 1-5, where higher scores mean better performances', 'timeFrame': 'after the end of treatment period (4 weeks from baseline)'}
- {'measure': 'Viking Speech Scale (VSS)', 'description': 'Ordinal scale for intelligibility, range 1-4, with lower scores corresponding to better performances', 'timeFrame': 'after the end of treatment period (4 weeks from baseline)'}

Please estimate the sample size based on the assumption: 
20% attrition rate, recruitment over 2 years, group randomization, standards of research consent.
Sample size
        Based on the yearly number of children referred to the recruiting center for clinical management and rehabilitation, we expect to reach a convenient final sample of 60 subjects with CP and motor speech disorders (including intervention and wait-list) over a 2 years period, by considering a conservative 20% attrition rate for clinical trials. Recruitment will be completed according to the standards of research consent, followed by group randomization by a team member other than the SLPs in charge of treatment and assessment.