Population Genetic Characteristics of the STR Loci D21S11 and FGA in Eight Diverse Human Populations

A highly polymorphic multiplex short tandem repeat (STR) system composed of D21S11, FGA, and the sex-typing system amelogenin (AMG) has been used to investigate allele frequency distributions in two Canadian Caucasian samples (British Columbia and Alberta), three Canadian aboriginal populations (Coastal Salishans from British Columbia, Ojibwa from northern Ontario, and Cree from Saskatchewan), and three ethnic groups from Singapore (Chinese, Malays, and Asian Indians). Using the automated fluorescence detection approach on an ABD 373A DNA Sequencer, we distinguished 20 D21S11 and 22 FGA alleles with a nearly equal representation of two- and four-base variants. An overlap in allele sizes for both STR loci across populations was observed, but frequency differences were noted. Statistical analysis revealed that (1) both D21S11 and FGA loci conform to Hardy-Weinberg equilibrium in all eight surveyed populations based on five different tests and (2) both STR loci are in linkage equilibrium. Results from the 2 X N contingency table exact tests for population differentiation demonstrated that the Canadian samples from two different provinces were not distinguishable from one another at either STR locus and therefore could be combined to form one Caucasian group. Likewise, Chinese and Malays from Singapore did not show significant differences at either STR locus. In contrast, all other examined populations exhibited differences deemed statistically significant. As a complement to our study, we compared D21S11 allele frequency distributions in 21 worldwide populations and FGA allele frequency distributions in 14 populations. Many alleles never previously reported in worldwide populations were identified in Canadian aboriginal and Asian samples from this study. Twenty-four D21S11 and 29 FGA alleles were distinguished in worldwide groups. Interesting similarities in allele frequency distribution patterns across populations suggest that the STR polymorphism at these loci predates the geographic dispersal of ancestral human populations. This study further demonstrates the utility of highly informative STR loci such as D21S11 and FGA in human population evolutionary history and in forensic medicine

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London