Surgical Quality Assurance in COLOR III : Standardization and Competency Assessment in a Randomized Controlled Trial

OBJECTIVE: The aim of this study was to develop an objective and reliable surgical quality assurance system (SQA) for COLOR III, an international multicenter randomized controlled trial (RCT) comparing transanal total mesorectal excision (TaTME) with laparoscopic approach for rectal cancer. BACKGROUND OF SUMMARY DATA: SQA influences outcome measures in RCTs such as lymph nodes harvest, in-hospital mortality, and locoregional cancer recurrence. However, levels of SQA are variable. METHOD: Hierarchical task analysis of TaTME was performed. A 4-round Delphi methodology was applied for standardization of TaTME steps. Semistructured interviews were conducted in round 1 to identify key steps and tasks, which were rated as mandatory, optional, or prohibited in rounds 2 to 4 using questionnaires. Competency assessment tool (CAT) was developed and its content validity was examined by expert surgeons. Twenty unedited videos were assessed to test reliability using generalizability theory. RESULTS: Eighty-three of 101 surgical tasks identified reached 70% agreement (26 mandatory, 56 optional, and 1 prohibited). An operative guide of standardized TaTME was created. CAT is matrix of 9 steps and 4 performance qualities: exposure, execution, adverse event, and end-product. The overall G-coefficient was 0.883. Inter-rater and interitem reliability were 0.883 and 0.986. To enter COLOR III, 2 unedited TaTME and 1 laparoscopic TME videos were submitted and assessed by 2 independent assessors using CAT. CONCLUSION: We described an iterative approach to develop an objective SQA within multicenter RCT. This approach provided standardization, the development of reliable and valid CAT, and the criteria for trial entry and monitoring surgical performance during the trial

Effects of High Temperature on the Residual Performance of Portland Cement Concretes

In this work we analyzed the "residual" performance of Portland cement concretes heat-treated at 600 °C after cooling down to room temperature. Concretes with characteristic compressive strength at 28 days of 45 MPa and of 60 MPa were studied. The heat-treatment was carried out without any imposed load. We measured the residual compressive strength and modulus of elasticity. The geometry of the structure was described by mercury intrusion porosimetry and nitrogen sorption tests. We observed a decrease of residual compressive strength and modulus of elasticity, with the raise of heat-treatment temperature, as a result of heat-induced material degradation. The results also indicated that the microstructural damage increased steadily with increasing temperature. Based on the results of this experimental work we concluded that residual mechanical properties of concrete are dependent of their original non heat-treated values

Structural Evaluation and Performance of Portland Cement Concretes After Exposure to High Temperatures

We evaluated the "residual" thermal conductivity of Portland cement concretes (with characteristic compressive strength at 28 days, f ck, of 20 MPa and 50 MPa) at room temperature after heat-treating at 180 °C, 300 °C and 600 °C. The description of the geometry of the structure was carried out using mercury intrusion porosimetry and nitrogen sorption. The results showed a decreasing tendency of residual thermal conductivity, which we attributed to heat-induced concrete degradation. Furthermore, the results from mercury intrusion porosimetry and nitrogen sorption tests showed that a coarser pore structure is produced with the raise of heat-treatment temperatures