Effects of school-level and area-level socio-economic factors on elementary school student COVID-19 infections: a population-based observational study.

OBJECTIVES: To estimate the variability of the cumulative incidence of SARS-CoV-2 infections among elementary school students attributable to individual schools and/or their geographic areas, and to ascertain whether socio-economic characteristics of school populations and/or geographic areas may be predictive of this variability. DESIGN: Population-based observational study of SARS-CoV-2 infections among elementary school children. SETTING: 3994 publicly funded elementary schools in 491 forward sortation areas (designated geographic unit based on first three characters of Canadian postal code), Ontario, Canada, September 2020 to April 2021. PARTICIPANTS: All students attending publicly funded elementary schools with a positive molecular test for SARS-CoV-2 reported by the Ontario Ministry of Education. MAIN OUTCOME MEASURES: Cumulative incidence of laboratory-confirmed elementary school student SARS-CoV-2 infections in Ontario, 2020-21 school year. RESULTS: A multilevel modelling approach was used to estimate the effects of socio-economic factors at the school and area levels on the cumulative incidence of elementary school student SARS-CoV-2 infections. At the school level (level 1), the proportion of the student body from low-income households was positively associated with cumulative incidence (ß=0.083, p<0.001). At the area level (level 2), all dimensions of marginalisation were significantly related to cumulative incidence. Ethnic concentration (ß=0.454, p<0.001), residential instability (ß=0.356, p<0.001) and material deprivation (ß=0.212, p<0.001) were positively related, while dependency (ß=-0.204, p<0.001) was negatively related. Area-related marginalisation variables explained 57.6% of area variability in cumulative incidence. School-related variables explained 1.2% of school variability in cumulative incidence. CONCLUSIONS: The socio-economic characteristics of the geographic area of schools were more important in accounting for the cumulative incidence of SARS-CoV-2 elementary school student infections than individual school characteristics. Schools in marginalised areas should be prioritised for infection prevention measures and education continuity and recovery plans.

Attending Surgeons Demonstrate Greater Correlations of Skill Assessment and Anticipation of Adverse Events Than Residents During Laparoscopic Cholecystectomy.

BACKGROUND: Surgical training includes the development of technical and nontechnical skills. While technical skills are more easily quantified, nontechnical skills such as situation awareness (SA) are more difficult to measure and quantify. This study investigated the relationships between different SA elements and expertise. METHODS: Twenty attending and resident surgeons rated their anticipation of an impending adverse event while watching 20 videos of laparoscopic cholecystectomies with and without adverse events. After watching each video, they assessed surgeon skills and self-assessed their anticipation ratings. All participants answered a general confidence questionnaire before and after the study. RESULTS: Videos with adverse events led to significantly higher anticipation of adverse events (P < 0.001), lower surgeon skill rating (P < 0.001), and higher self-assessment in their anticipation ratings (P < 0.001) across both participant groups. General confidence was significantly lower for residents than that for attending surgeons (P < 0.001). Compared with the residents, attendings exhibited stronger and more stable correlations between measurements of SA. When viewing videos with adverse events, attendings showed significantly higher correlation between anticipation of an impending adverse event and skill assessment of the surgeon (P = 0.005). CONCLUSIONS: This study investigated how different elements of SA and their relationships were influenced by experience. The results indicated that attendings had stronger and more stable correlations between SA elements than residents, demonstrating how measurement correlations could be meaningful and sensitive indicators of expertise and autonomy readiness.