Here is the design of a clinical trial:

Official Title: Efficacy and Safety of Fecal Microbiota Transplantation (FMT) in Patients With Peripheral Psoriatic Arthritis: a 6-month, Double-Blind, Randomized, Placebo-Controlled Trial

Included conditions:
- Psoriatic Arthritis

Study Armgroups:
- {'label': 'Fecal microbiota transplantation (FMT)', 'type': 'EXPERIMENTAL', 'interventionNames': ['Drug: Fecal microbiota transplantation (FMT)', 'Drug: Methotrexate (MTX)']}
- {'label': 'Placebo (saline)', 'type': 'SHAM_COMPARATOR', 'interventionNames': ['Other: Drug: Placebo (saline)', 'Drug: Methotrexate (MTX)']}

Interventions:
- {'type': 'DRUG', 'name': 'Fecal microbiota transplantation (FMT)', 'description': 'One fecal microbiota transplantation is performed at baseline using gastroscopic guidance. The transplant consists of 50 g feces obtained from a healthy non-related donor. The donor feces is suspended into NaCl (0.9%) and glycerol (10%), and will be stored at minus 80 degrees celsius until use. The total volume of the suspension is 250 mL and its temperature will be 37 degrees celsius when infused into the small intestine of the recipient.', 'armGroupLabels': ['Fecal microbiota transplantation (FMT)']}
- {'type': 'OTHER', 'name': 'Drug: Placebo (saline)', 'description': 'One identical appearing sham procedure is performed at baseline using gastroscopic guidance. 250 mL saline (NaCl 0.9%) is infused into the small intestine of the recipient.', 'armGroupLabels': ['Placebo (saline)']}
- {'type': 'DRUG', 'name': 'Methotrexate (MTX)', 'description': 'Weekly methotrexate in maximum tolerable dosis', 'armGroupLabels': ['Fecal microbiota transplantation (FMT)', 'Placebo (saline)']}

Primary Outcomes:
- {'measure': 'Treatment failure', 'description': 'Proportion of patients in each group who experience treatment failure according to shared decision making between patient and rheumatologist defined as at least one of the following:\n\n* Need for more than 1 intra-articular glucocorticoid injection due to disease activity.\n* Need for change to other conventional DMARDs (at the moment oral leflunomide, sulfasalazin or ciclosporin) according to the updated Danish guideline treatment due to disease activity.\n* Need for biologic treatment according to the updated Danish guideline treatment due to severe disease activity.', 'timeFrame': '6 months (+/- 14 days)'}

Please estimate the sample size based on the assumption: 
The trial uses a two-sided significance level of 0.05 and aims for a power of 90% (0.895) for the primary comparison. It also considers a power of 80% (0.8) to account for a potential dropout rate of 20%. For secondary outcomes, a power of 82% is assumed.
Sample size and power considerations
        When designing this trial, no prior data for FMT efficacy in patients with rheumatic disease were available. However, we found it reasonable to assume that if patients withÂ rheumatic disease should be willing to receive FMT as a future standardised treatment, the procedure should at least provide an effect size well beyond a moderate effect size. Consequently, we decided that at least twice as many patients with PsA in the sham group should be treatment failures compared with the FMT group if the procedure should be considered clinically relevant. For a comparison of two independent binomial proportions using the Pearsonâs Î§2 statistic with a Î§2 approximation (a two-sided significance level of 0.05), a sample size of 40 patients with PsA per group has a power of 90% (0.895), if we assume that the proportions of treatment failures are 35% (FMT-active group) and 70% (FMT-sham group), respectively. Consequently, the inclusion of 80 patients with PsA allocated (1:1) to two treatment arms is believed to be sufficient to reveal any difference of clinical importance between treatment groups (ie, an Number needed to treat (NNT) <3 patients).
        Assuming that there will be some attrition during the 6-month trial period, we also estimated how much dropout would be possible while still having a reasonable statistical power (80%): a total sample size of 62 patients with PsA assuming a comparable level of withdrawals (31 patients completing in each group) achieves a power of at least 0.8 with the proportion of treatment failures indicated above, thatÂ is, even if we experience a dropout rate of 20%, our trial will have 80% chance of detecting the intentional difference between groups.
        Beyond the primary endÂ point, a total sample size of 80 (with a balanced design) corresponds to a sufficient statistical power (82%) to detect a standardised mean difference of 0.65 SD units (ie, Cohenâs effect size) in any of the patient-reported outcome measures.