Here is the design of a clinical trial:

Official Title: Efficacy of a Training Program in Mindfulness and Self-Compassion of 4 Sessions in Front of the 8 Sessions to Reduce Work Stress and Burnout in Professionals of Medicine and Nursing (MINDUUDD Project)

Included conditions:
- Stress
- Burnout Syndrome

Study Armgroups:
- {'label': 'Intervention group 4s (mindfulness)', 'type': 'EXPERIMENTAL', 'description': 'Abbreviated program of 4 weeks: will consist of 4 weekly sessions of 2 hours. Participants must practice at home for 15 minutes a day', 'interventionNames': ['Behavioral: Mindfulness and Mindful Self-Compassion']}
- {'label': 'Intervention group 8s (mindfulness)', 'type': 'EXPERIMENTAL', 'description': 'Program of 8 weeks: The format will be 8 weekly sessions of 2 hours. Participants must practice at home for 30 minutes a day', 'interventionNames': ['Behavioral: Mindfulness and Mindful Self-Compassion']}
- {'label': 'Control group', 'type': 'NO_INTERVENTION', 'description': 'The participants will only receive a one-hour information session and will be invited to complete the questionnaires provided in two moments of the time (coinciding with the interventions in the experimental groups)'}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'Mindfulness and Mindful Self-Compassion', 'description': 'Mindfulness Based Stress Reduction (MBSR) and Mindful Self-Compassion', 'armGroupLabels': ['Intervention group 4s (mindfulness)', 'Intervention group 8s (mindfulness)']}

Primary Outcomes:
- {'measure': 'Degree of occupational stress', 'description': 'An ordinal scale that ranges from 0 (no degree of stress) to 10 (maximum degree of stress) stress, will be used', 'timeFrame': 'Change from baseline at 4 weeks (EG4) or 8 weeks (EG8 or CG)'}
- {'measure': 'Degree of occupational stress', 'description': 'PSQ questionnaire (Perceived Stress Questionnaire). It consists of 30 items that can be scored using a Likert scale (1 to 4). Higher total values indicate more stress.', 'timeFrame': 'Change from baseline at 4 weeks (EG4) or 8 weeks (EG8 or CG)'}
- {'measure': 'Degree of burnout', 'description': 'Maslach Burnout Inventory-General Survey (MBI). Spanish version of the MBI-HSS25. It consists of 22 scoring items from 0 to 6 that measure the three dimensions of the syndrome: emotional fatigue (CE), 9 items and a maximum score of 54 points; depersonalization (DP), 5 items and maximum score of 30 points; personal fulfillment (RP), 8 items and maximum score of 48 points. The cut points used were: emotional fatigue under \\<19, moderate 19-26, high\\> 26. Depersonalization under \\<6, moderate 6-9, high\\> 9. Personal performance under\\> 39, moderate 39-34, high \\<34 .', 'timeFrame': 'Change from baseline at 4 weeks (EG4) or 8 weeks (EG8 or CG)'}
- {'measure': 'Degree of Self-Compassion', 'description': 'Self-compassion questionnaire. The short scale of the Spanish version, validated by García-Campayo et al, will be used, with 12 items scored using a Likert scale (1 to 5) that measures how the subject usually acts towards himself in difficult moments. It consists of six subscales: self-friendliness, common humanity, mindfulness, and their opposites: self-judgment, isolation and over-identification. Higher total values indicate more self-pity.', 'timeFrame': 'Change from baseline at 4 weeks (EG4) or 8 weeks (EG8 or CG)'}

Please estimate the sample size based on the assumption: 
Alpha risk of 0.05, beta risk of 0.2 (power of 80%), and a loss/withdrawal rate of 25%. The design effect for cluster randomisation is considered with a factor of 1.7 based on an intra-cluster correlation coefficient (ICC) of < 0.05 for a cluster size of 15.
Sample size
        To calculate the sample size, we have drawn on a previous study [25], using as an outcome variable the mean FFMQ score [31]; accepting an alpha risk of 0.05 and a beta risk of 0.2, in a bilateral contrast, 38 subjects are required in each group to detect a differenceââ¥â15 points in the FFMQ scale between both experimental groups (EG4 and EG8) and the CG. It is assumed that the common standard deviation is 20. A loss or withdrawal rate of 25% has been estimated [43]. Because this is a cluster randomisation study, we have considered the design effect. The design effect multiplies the sample size by a factor ranging from 1.5 to 3 to achieve the same power, depending on the relationship between intra- and intergroup variance [44]. Estimates of the intra-cluster correlation coefficient (ICC) in randomised clinical trials in AP are generally <â0.05 [45]. This ICC, for a cluster size of 15, results in a design effect corresponding to a factor of 1.7. Assuming this value, the final study sample size would be at least 130 subjects. One hundred and thirty-two (132) professionals will be included, 44 in each comparison group, 22 for each teaching unit.