Variability in Celiac Serology Testing by Provider Type: A Single-Center Experience.

Celiac disease diagnostic testing varies across provider types, but the extent of this variability remains unclear. While established guidelines exist for serological testing, real-world adherence is poorly characterized. Prior research has shown that testing protocols differ by specialty and clinical setting. However, no prior work had resolved how consistently provider types follow recommended testing algorithms. This gap motivated an analysis of celiac serology ordering practices at a single academic children’s hospital. No prior work had resolved whether provider type influences adherence to best practices in serology testing. That uncertainty drove a need to evaluate how frequently providers order recommended tests versus alternative or less effective options. This gap motivated a study of provider-specific patterns in serology testing for celiac disease.

The study aimed to evaluate how consistently providers order celiac disease serologies according to established guidelines. It focused on identifying patterns of adherence and deviation among different provider types. The specific problem addressed was the lack of understanding about how provider specialty influences serology testing decisions. This study sought to compare ordering practices to best practices and clinical guidelines. The motivation stemmed from the potential impact of inconsistent testing on diagnostic accuracy. The goal was to assess whether provider type correlates with appropriate serology panel selection. The study also aimed to identify which provider groups most frequently deviate from recommended testing protocols. This analysis could inform quality improvement initiatives in pediatric celiac disease screening.

The study used a retrospective analysis of celiac serology orders from a single academic children’s hospital in 2018. Researchers categorized orders by provider type—pediatric gastroenterologists, primary care providers, and nonpediatric gastroenterologists. They evaluated the frequency of specific antibody tests, including tTG IgA, tTG IgG, DGP IgA/IgG, and antiendomysial antibody. They also assessed whether total IgA was ordered alongside screening tests. The team compared ordering patterns to published guidelines and best practices. They calculated positivity rates for tTG IgA by provider type. Researchers identified cases where tests were ordered in error or without appropriate accompanying tests. This approach allowed them to quantify adherence and variability across provider types.

The most frequently ordered test was tTG IgA, with gastroenterologists ordering it in 43% of cases. Endocrinologists ordered tTG IgA in 22% of cases. Total IgA was ordered alongside tTG IgA in 81% of cases overall, but only 49% of endocrinologists included it. DGP IgA/IgG was ordered in only 5.4% of cases. Antiendomysial antibody was ordered in just 0.9% of cases. Celiac genetic tests were ordered in 0.8% of cases, but 15% of these were ordered in error. PCPs had a tTG IgA positivity rate of 4.4%. Endocrinologists frequently omitted total IgA testing with screening labs. One provider inappropriately ordered DGP IgA/IgG. These findings suggest underutilization of nonbiopsy diagnostic approaches.

The study found that provider type significantly influences celiac serology ordering practices. Gastroenterologists most frequently ordered tTG IgA, while endocrinologists showed lower adherence to guidelines. Total IgA was frequently omitted when ordered by endocrinologists. DGP IgA/IgG and antiendomysial antibody were rarely ordered, suggesting limited use of nonbiopsy approaches. Celiac genetic tests were ordered in error in 15% of cases. PCPs had a higher tTG IgA positivity rate compared to prior studies. These findings suggest variability in adherence to best practices. The results highlight opportunities for standardizing serology testing protocols. The study supports the need for provider-specific education on celiac disease testing guidelines.