Here is the design of a clinical trial:

Official Title: A Randomised Designed Clinical Investigation of the Use of a Personalised Early Warning Decision Support System With Novel Saliva Bio-profiling to Predict and Prevent Acute Exacerbations of Chronic Obstructive Pulmonary Disease

Included conditions:
- Chronic Obstructive Pulmonary Disease

Study Armgroups:
- {'label': 'Usual care', 'type': 'ACTIVE_COMPARATOR', 'description': 'Patients currently self-manage their condition using antibiotics and steroids when their disease symptoms match the criteria in information provided by a clinician', 'interventionNames': ['Other: Usual care']}
- {'label': 'Mobile App device', 'type': 'EXPERIMENTAL', 'description': 'Patients enter their health status onto an App which is relayed to the healthcare team, who can then provide further information or clinical intervention should they so choose', 'interventionNames': ['Device: COPDPredict mobile App']}

Interventions:
- {'type': 'DEVICE', 'name': 'COPDPredict mobile App', 'description': "An App on a mobile device is used by the patient to track the status of their COPD and inform the patient's care team", 'armGroupLabels': ['Mobile App device']}
- {'type': 'OTHER', 'name': 'Usual care', 'description': 'Patients self-manage their COPD using prescribed medication in accordance with basic guidance information', 'armGroupLabels': ['Usual care']}

Primary Outcomes:
- {'measure': 'AECOPD-related hospital admissions', 'description': 'The number of AECOPD-related hospital admissions', 'timeFrame': 'For a period of 12 months post randomisation'}

Please estimate the sample size based on the assumption: 
90% power, 5% type I error rate (two-sided), 25% loss to follow-up/drop-out rate
Sample size
        The justification of the sample size is based on previous evidence25 that had shown a mean estimate of 2.5 COPD admissions in the previous year in the control group. To detect a difference of 1 admission in the mean number of admissions between groups using the standard methods of difference between means and assuming SD of 2.6 with 90% power and a type I error rate of 5% (two-sided), 144 participants per group will need to be randomised, 288 in total. Assuming and adjusting for a 25% loss to follow-up/ drop-out rate, 384 participants will need to be recruited.