Here is the design of a clinical trial:

Official Title: A Nurse-led Patient-centred Intervention to Increase Written Advance Directives for Outpatients With Progressive Chronic Illnesses: a Randomized Controlled Trial With an Embedded Explanatory Qualitative Study

Included conditions:
- Advance Care Planning
- Outpatients
- Palliative Care

Study Armgroups:
- {'label': 'CG', 'type': 'ACTIVE_COMPARATOR', 'description': 'control group receiving the usual care, the standardized information on anticipated directives', 'interventionNames': ['Other: usual care']}
- {'label': 'IG p+r', 'type': 'ACTIVE_COMPARATOR', 'description': 'intervention group with patients and her/his relative', 'interventionNames': ['Other: serious game named Go Wish']}
- {'label': 'IG p', 'type': 'ACTIVE_COMPARATOR', 'description': 'intervention group with patients without relative', 'interventionNames': ['Other: serious game named Go Wish']}

Interventions:
- {'type': 'OTHER', 'name': 'serious game named Go Wish', 'description': "The nurse led intervention Go Wish is composed of 36 cards presenting statements of personal needs, values, and beliefs about end-of-life care. The aim is to decide about what to put into the patient's file as care options and the subsequent appointments to name a potential surrogate or to elaborate ADs.\n\nPatient and relative (if participating) will meet their nurse twice:\n\nSession 1: patient the cards in three piles and to rank the ten most important. Session 2 without relative: the nurse reiterates the wishes of care and treatments previously expressed and links them to the state of health and symptoms of the patient and the current treatments and their possible evolution.\n\nSession 2 with a relative: the relative sort the cards based on his/her beliefs about the patient's expectation.\n\nSession 3 with a relative: the nurse bring together the patient and his/her relative to discuss the priorities selected independently, identify, and explore the similarities and differences.", 'armGroupLabels': ['IG p', 'IG p+r']}
- {'type': 'OTHER', 'name': 'usual care', 'description': 'Standardized information on anticipated directives (ADs): the imad nurse are trained to promote AD to clients to help nurses to describe and explain ADs, to identify and to mobilize the required interview condition to promote ADs to clients to facilitate and initiate discussion on ADs', 'armGroupLabels': ['CG']}

Primary Outcomes:
- {'measure': 'Number of completed anticipated directives', 'description': 'Completion of anticipated directives will be coded "yes" when anticipated directives are written and signed, otherwise it will be coded "no"', 'timeFrame': '6 months after inclusion'}

Please estimate the sample size based on the assumption: 
With a significance level of 0.05, a power of 0.8, and an attrition rate of 20%.
Sample size
          The percentage of the population with completed ADs in Switzerland has been estimated at around 2%.8 9 We anticipate that 5âmonths after inclusion in the study, around 5% of the patients of Group B will have ADs and around 25% of the patients of group A will have ADs. With a significance level of 0.05, a power of 0.8, and an attrition rate of 20%, we need to include 45 patients in each group to show the superiority of intervention A on the proportion of patients with completed ADs, as compared with intervention B.
          Go Wish was first developed for patients only28 and later for dyads (patients and relatives),27 to increase its beneficial effects. For ethical reasons, and to not stigmatise patients without relatives, the recruitment for the intervention group will be doubled to 45 patients with relatives and 45 patients without relatives. We will test the interventionâs efficacy for those with (hypothesis 1a) and without relatives (hypothesis 1b). Group B will include 45 patients (with or without relatives, with around 20 relatives). We will recruit a total of 135 patients receiving imad services and around 65 relatives. Twenty nurses are needed to recruit 135 patients (with an average of 25 patients referred to each nurse during the 15 months of the study; 60% in early-stage palliative care and a 50% response rate)â.
          For the second study, we will randomly select 5â10 patients, relatives and nurses in each group until data saturation.