Grodzinsky, et al:
High Prevalence of Celiac Disease in Healthy Adults Revealed by anti-gliadin Antibodies
ANNALS OF ALLERGY vol.69, July 1992, p. 66-70.
This study was done by testing random blood samples from healthy blood donors. Donors with elevated levels were asked to undergo endoscopic examination. Some refused. One in 256 of those who underwent endoscopy were identified as having celiac disease. Everyone in this study thought themselves healthy enough to be donating blood without being asked to do so. Extrapolating from the number who consented to endoscopy, had the ratio remained constant, the proportion would have been One in 187. Again, these were healthy blood donors, not folks in a GI department of a hospital.
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BMJ 2004;328:322-323 (7 February) Celiac.com 02/18/2004 - A study conducted by researchers in the UK has found that 1% of all seven year old children in the UK have celiac disease, and most cases of celiac disease continue to remain undiagnosed. The researchers tested 5,470 "normal" children using a two stage screening that included an initial radioimmunoassay for antibodies to tissue transglutaminase (endomysial antigen), and a further testing of positive samples for IgA-EMA by indirect immunofluorescence. Children with tTG antibodies under the 97.5th percentile were defined as antibody negative. Out of those tested 54 were positive for IgA-EMA. Additionally: "IgA-EMA positive children were shorter and weighed less than those who tested negative for tTG antibody."
The Researchers...

Celiac.com 03/27/2015 - Researchers don't have any solid idea about how common cases of seronegative celiac disease might be, but many feel strongly that rates of seronegative celiac disease are underestimated in children, and may result in misdiagnosis of celiac cases.
One team of researchers wondered if an emphasis on "serology-led" diagnosis might be contributing to a low rate of celiac disease diagnosed in children from the United States. That research team included Deborah L. Preston and Yoram Elitsur, and they recently set out to investigate the rate of celiac disease after upper endoscopy (EGD) with no prior positive celiac serology compared with the rate of celiac disease followed by positive serology.
The team conducted a retrospective review of that charts of all of the ...