Here is the design of a clinical trial:

Official Title: Inhaler Technique Education in Elderly Patients With Asthma or COPD: Impact on Disease Exacerbations - a Protocol for a Single-blinded Randomised Controlled Trial

Included conditions:
- Asthma
- COPD

Study Armgroups:
- {'label': 'Inhaler technique education', 'type': 'EXPERIMENTAL', 'description': 'This group will receive a structured and regular follow-up plan, with education on inhaler technique. Patients will be trained by a Family Doctor (the primary investigator) in terms of the inhaler technique using placebo devices similar to their own devices. A teach-to-goal approach will be used, repeating all correct steps as many times as needed in order for patients to perform them correctly at each evaluation. There will be visits at baseline and after 3, 6 and 12 months to assess outcomes. In each visit, and prior to the main intervention with the primary investigator, assessment of the inhaler technique and application of all questionnaires (clinical control, treatment adhesion and quality of life) will be performed by a secondary blinded investigator.', 'interventionNames': ['Behavioral: Inhaler technique education']}
- {'label': 'Usual Care', 'type': 'NO_INTERVENTION', 'description': 'This group will receive usual care from their own Family doctors, with no specific intervention. Each doctor will perform the necessary consultations according to his real life judgment. Besides this, this group will perform visits at baseline and after 3, 6 and 12 months to assess secondary outcomes. At each visit, assessment of the inhaler technique and application of all questionnaires (clinical control, treatment adhesion and quality of life) will be performed by a secondary blinded investigator. At any appointment, if the patient asks for or if the clinician decides to teach inhaler technique, that will be recorded.\n\nIf any adjustments are made in drug classes or device types in every participants, this information will be recorded.'}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'Inhaler technique education', 'description': 'Teaching of inhalers use with placebo devices in real training', 'armGroupLabels': ['Inhaler technique education']}

Primary Outcomes:
- {'measure': 'Adverse events', 'description': 'This outcome will be quantifyed as "time to event"\n\nFor Asthma, an event will be defined as increased respiratory clinical symptoms leading the patient to search for medical care, and resulting in any of the following:\n\n* Need for increased inhaled corticosteroid dose of at least 4x the regular dose\n* Need for increase of short-acting β2 agonists on a daily basis\n* Need for oral corticosteroids\n* Need for oral antibiotics\n* Hospitalization or Emergency Room (ER) visit with increased respiratory clinical symptoms.\n\nFor COPD, an event will be defined as increased respiratory clinical symptoms inducing the patient to search for medical care, and resulting in any of the following:\n\n* Need for increase of long-acting β2 agonists on a daily basis\n* Need for oral corticosteroids\n* Need for oral antibiotics\n* Hospitalization or ER visit with increased respiratory clinical symptoms. Respiratory-related mortality and all-cause mortality will also be considered an adverse event.', 'timeFrame': 'Evaluation at 12 months.'}

Please estimate the sample size based on the assumption: 
95% CI, power of 80%, alpha level of 5%, ratio of cases/controls of 1:1, and 20% loss rate
Sample size calculation
        Sample size was estimated using the ÏÂ² independent group proportions approach of STATA Statistical Package, considering the event proportion in control group of 50% (0.5 annual rate) as reported in other previous studies21 22 44 and estimating a reduction of event rate in the intervention group to 25% (0.25 annual rate) as reported in similar studies. A 95% CI, with Î² value (power) of 80%, an alpha level of 5% and a ratio of cases/controls of 1:1 were established. Finally, the sample size was readjusted upward, considering an estimated proportion of full compliance of the study of 80% (20% losses). The estimated sample size was 116, readjusted to a total of 146 individuals (73 in each arm).