Here is the design of a clinical trial:

Official Title: Cost-utility Evaluation of Two Strategies of Perineal Reconstruction After Abdominoperineal Resection for Anorectal Carcinoma: Perineal Filling With Biological Meshes vs. Primary Perineal Wound Closure

Included conditions:
- Abdominoperineal Resection

Study Armgroups:
- {'label': 'Arm with biological mesh', 'type': 'EXPERIMENTAL', 'description': 'The intervention consists of perinal reconstruction using biological mesh (Cellis prosthesis from Meccellis Biotech, reference C1015E size 10x15cm)', 'interventionNames': ['Procedure: Biological mesh']}
- {'label': 'Arm with primary perineal wound closure', 'type': 'ACTIVE_COMPARATOR', 'description': 'The intervention consists of perinal reconstruction by primary perineal wound closure', 'interventionNames': ['Procedure: Primary perineal wound closure']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Biological mesh', 'description': 'The intervention consists of suturing a biological mesh in the pelvic floor defect. The mesh will be sutured at each side of the coccyx or distal sacrum and directly to the residual pelvic floor muscle and fascia by using interrupted or continuous hand-sewn sutures with an appropriate amount of tension. The mesh that will be used is the Cellis prosthesis from Meccellis Biotech, reference C1015E which size is 10x15cm.', 'armGroupLabels': ['Arm with biological mesh']}
- {'type': 'PROCEDURE', 'name': 'Primary perineal wound closure', 'description': 'The intervention consists of stitching the ischioanal and subcutaneous fat using interrupted Vicryl sutures in one or two layers similar to primary perineal closure', 'armGroupLabels': ['Arm with primary perineal wound closure']}

Primary Outcomes:
- {'measure': 'Incremental Cost-Utility Ratio (ICUR)', 'description': 'The primary endpoint in this study is based on the assessment of the incremental cost-utility ratio at 1 year, from the collective perspective between biological mesh perineal reconstructions versus. primary perineal closure in patients operated for anorectal carcinoma with proven rectal adenocarcinoma or anal canal epidermoid carcinoma.', 'timeFrame': 'At 12 months'}

Please estimate the sample size based on the assumption: 
Two-sided t-test with a 5% significance level, 80% power for EQ-5D-5L and complication rate, 90% power for ICUR, and a 10% drop-out rate.
Sample size calculation
        The primary objective of this protocol is to assess the ICUR at 12 months of two surgical procedures of pelvic reconstruction. A difference of 0.5 SD for EQ-5D-5L between arm A and arm B will be considered clinically meaningful.15 This effect size will be detected with at least 80% power, using a two-sided t-test with a 5% two-sided significance level and a drop-out rate of 10%.
        Furthermore, based on the literature which indicates that the rate of early complications following conventional primary perineal wound closure may range between 35% and 65% (Foster colorectal disease 2012), a sample size of 140 patients will also provide at least 80% power assuming an absolute difference in complication rate of 25% (with the conventional arm response at 45%). The other parameters used in the calculation are a two-sided Î§2 test with a two-sided significance level of 0.05, a drop-out rate of 10%.
        Additionally, the sample size was calculated according to the ICUR using the Glick formula. ICUR will result in cost per quality-adjsted life-year (QALY).16 According to a study conducted in 2012, the cost difference will be ââ¬5704 (SD â¬8000) in favour of biological meshes.5 According to a study assessing the significant minimum difference in terms of QALY, we estimate a difference of 0.06 (SD 0.20) in favour of biological meshes.17 The correlation coefficient was estimated at â0.6 using an analysis of variance. The willingness-to-pay threshold has been set at â¬50 000. This effect size will be detected with at least 90% power, using a two-sided t-test with a 5% two-sided significance level. The drop-out rate has been set at 10%. The total sample size was evaluated at 132, in other words 66 patients to be recruited per arm.
        The calculation of the number of subjects to be included in the study, using the Glick formula, was carried out based on conservative assumptions in terms of cost of care and utility. In fact, the cost difference was calculated using inflated costs (â¬2020) and all the complications avoided, thanks to biological meshes, those were not included in the cost calculation. Furthermore, concerning the significant minimum difference of QALY, the article by Walters et al proposes a mean of 0.074 and an SD of 0.10. We have chosen to include in our calculation an average difference of 0.06 and an SD of 0.2.