Validation of a risk prediction model for Barrett’s esophagus in an Australian population

Abstract

Background

Esophageal adenocarcinoma is a disease that has a high mortality rate, the only known precursor being Barrett’s esophagus (BE). While screening for BE is not cost-effective at the population level, targeted screening might be beneficial. We have developed a risk prediction model to identify people with BE, and here we present the external validation of this model.

Materials and methods

A cohort study was undertaken to validate a risk prediction model for BE. Individuals with endoscopy and histopathology proven BE completed a questionnaire containing variables previously identified as risk factors for this condition. Their responses were combined with data from a population sample for analysis. Risk scores were derived for each participant. Overall performance of the risk prediction model in terms of calibration and discrimination was assessed.

Results

Scores from 95 individuals with BE and 636 individuals from the general population were analyzed. The Brier score was 0.118, suggesting reasonable overall performance. The area under the receiver operating characteristic was 0.83 (95% CI 0.78–0.87). The Hosmer–Lemeshow statistic was p=0.14. Minimizing false positives and false negatives, the model achieved a sensitivity of 74% and a specificity of 73%.

Conclusion

This study has validated a risk prediction model for BE that has a higher sensitivity than previous models.

Keywords:

• Barrett’s esophagus
• risk prediction model
• screening
• validation

Acknowledgments

The authors would like to thank Dr Tom Laws, School of Health and Society, University of Salford, England, for his support. Assistance with accessing the endoscopy database to identify potential participants with Barrett’s esophagus was provided by The Department of Gastroenterology and Hepatology, Royal Adelaide Hospital.

The retrospective population dataset was collected as part of The Study of Digestive Health. Study of Digestive Health Investigators were as follows: Queensland Institute of Medical Research, Brisbane, Australia: David C Whiteman, MBBS, PhD; Adele C Green, MBBS, PhD; Nicholas K Hayward, PhD; Peter G Parsons, PhD; Sandra J Pavey, PhD; David M Purdie, PhD; Penny M Webb, DPhil. University of Queensland, Brisbane, Australia: David Gotley FRACS; Mark Smithers FRACS. The University of Adelaide, Adelaide, Australia: Glyn G Jamieson FRACS. Flinders University, Adelaide, Australia: Paul Drew, PhD; David I Watson FRACS. Envoi Pathology, Brisbane, Australia: Andrew Clouston, PhD, FRCPA. The Study of Digestive Health was supported by grant number RO1 CA 001833 from the National Cancer Institute. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute. CJI receives support through an Australian Government Research Training Program Scholarship.

Disclosure

The authors report no conflicts of interest in this work.