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Endoscopist biopsy rate as a quality indicator for outpatient gastroscopy: a multicenter cohort study with validation
Wladyslaw Januszewicz1, Paulina Wieszczy2, Andrzej Bialek3
1Department of Gastroenterological Oncology, The Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology, Warsaw, Poland; Department of Gastroenterology, Hepatology and Clinical Oncology, Medical Centre for Postgraduate Education, Warsaw, Poland; MRC Cancer Unit, University of Cambridge, Cambridge, United Kingdom.
Background And Aims:
The diagnosis of gastric premalignant conditions (GPCs) relies on endoscopy with mucosal sampling. We hypothesized that the endoscopist biopsy rate (EBR) might constitute a quality indicator for EGD, and we have analyzed its association with GPC detection and the rate of missed gastric cancers (GCs).
Methods:
We analyzed EGD databases from 2 high-volume outpatient units. EBR values, defined as the proportion of EGDs with ≥1 biopsy to all examinations were calculated for each endoscopist in Unit A (derivation cohort) and divided by the quartile values into 4 groups. Detection of GPC was calculated for each group and compared using multivariate clustered logistic regression models. Unit B database was used for validation. All patients were followed in the Cancer Registry for missed GCs diagnosed between 1 month and 3 years after EGDs with negative results.
Results:
Sixteen endoscopists in Unit A performed 17,490 EGDs of which 15,340 (87.7%) were analyzed. EBR quartile values were 22.4% to 36.7% (low EBR), 36.8% to 43.7% (moderate), 43.8% to 51.6% (high), and 51.7% and 65.8% (very-high); median value 43.8%. The odds ratios for the moderate, high, and very-high EBR groups of detecting GPC were 1.6 (95% confidence interval [CI], 1.3-1.9), 2.0 (95% CI, 1.7-2.4), and 2.5 (95% CI, 2.1-2.9), respectively, compared with the low EBR group (P < .001). This association was confirmed with the same thresholds in the validation cohort. Endoscopists with higher EBR (≥43.8%) had a lower risk of missed cancer compared with those in the lower EBR group (odds ratio, 0.44; 95% CI, 0.20-1.00; P = .049).
Conclusions:
The EBR parameter is highly variable among endoscopists and is associated with efficacy in GPC detection and the rate of missed GCs.
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