<<Disclaimer: Verify this information before applying it to your situation.>> Thanks to everyone who kindly did searches in an attempt to help me locate the 2.25:100 prevalence number I remember learning about on this list. The gold star goes to Ron Hoggan, who forwarded an extract summarizing the study I had in mind. Now I see that my memory was incorrect. The study measured prevalence in a population that had symptoms associated with celiac, not in a general healthy population. You can see the write-up, below. The most solid, current figure for the general population is, apparently, plus or minus 1:100. The information is spotty so far, but there are indications that 1:100 may apply to many peoples around the world and not just to populations of Northern European descent. If you wish more detail, do a search using the name Catassi. He's the researcher Dr. Green is quoting when he cites the 1:100 number. Thanks again, everyone. Mary B. NYC Am J Gastroenterol. 2007 Mar 13; [Epub ahead of print] Links Detection of Celiac Disease in Primary Care: A Multicenter Case-Finding Study in North America.Catassi C, Kryszak D, Louis-Jacques O, Duerksen DR, Hill I, Crowe SE, Brown AR, Procaccini NJ, Wonderly BA, Hartley M D P, Moreci J, Bennett N, Horvath K, Burk M, Fasano A. Mucosal Biology Research Center and Division of Pediatric Gastroenterology and Nutrition, University of Maryland School of Medicine, Baltimore, Maryland, USA. BACKGROUND: Celiac disease (CD) is one of the most common lifelong disorders in western countries. However, most cases remain currently undiagnosed in North America, mostly due to poor awareness of CD by primary care physicians. OBJECTIVES: The aims of this study were (a) to determine whether an active case-finding strategy in primary care could increase the frequency of CD diagnosis and (b) to determine the most common clinical presentations of the condition. METHODS:This was a multicenter, prospective study involving adult subjects during the years 2002-2004, attending one of the participating practices. All individuals with symptoms or conditions known to be associated with CD were tested for immunoglobulin A anti-transglutaminase (tTG) antibodies, and those with elevated anti-tTG were subsequently tested for IgA antiendomysial antibodies (EMA). All subjects who were positive for EMA were advised to undergo an intestinal biopsy and HLA typing. RESULTS: The study group included 737 women and 239 men, with a median age of 54.3 yr. A positive anti-tTG test was found in 30 out of 976 investigated subjects (3.07%, 95% CI 1.98-4.16). CD was diagnosed in 22 patients (18 women, 4 men). The most frequent reasons for CD screening in these 22 cases were bloating (12/22), thyroid disease (11/22), irritable bowel syndrome (7/22), unexplained chronic diarrhea (6/22), chronic fatigue (5/22), and constipation (4/22). The prevalence of CD in the serologically screened sample was 2.25% (95% CI 1.32-3.18). The diagnostic rate was low at baseline (0.27 cases per thousand visits, 95% CI 0.13-0.41) and significantly increased to 11.6 per thousand visits (95% CI 6.8-16.4, P < 0.001) following active screening implementation. CONCLUSIONS: This study demonstrates that an active case-finding strategy in the primary care setting is an effective means to improve the diagnostic rate of CD in North America. -- Visit the Celiac Web Page at Http://www.enabling.org/ia/celiac/index.html Archives are at: Http://Listserv.icors.org/SCRIPTS/WA-ICORS.EXE?LIST=CELIAC