Despite the many efforts to delineate the clinical manifestations of gallbladder disease, the precise symptom complex associated with gallstones is still a matter of debate, and even the existence of gallstone-specific symptoms has been questioned. We carried out a large population-based cross-sectional study (MICOL) to identify symptoms significantly related to gallstones. Fourteen centers throughout Italy enrolled 29,504 subjects aged 30 to 69 years. All subjects were administered an ultrasonographic examination of the upper abdomen and a precoded questionnaire. All subjects were divided into 4 groups: 25,374 (86.0%) gallstone-free subjects (GF), 1,832 (6.2%) patients with gallstones not previously diagnosed (GNPD), 638 (2.2%) patients with gallstones previously diagnosed (GPD), 1,660 (5.6%) patients with a history of cholecystectomy for gallstones (CC). In logistic regression analysis, pain at epigastrium and, even more, pain at right hypocondrium were significantly associated with gallstones. For pain at right hypocondrium, this association progressively increased from GNPD (OR ؍ 1.60, 95% CI ؍ 0.97-2.65) to GPD (OR ؍ 8.77, 95% CI ؍ 5.27-14.61) to CC (OR ؍ 59.40, 95% CI ؍ 43.87-80.42). Absence of heartburn combined with right hypocondrium or epigastrium pain and intolerance to fried or fatty food were also significantly related to gallstones. We also found some pain characteristics significantly associated with gallstones, i.e., pain radiated to the right shoulder, forcing the patient to rest, occurring soon after meals or unrelated to meals, not relieved by bowel movements, and frequently accompanied by gallstonerelated morbidities. We developed a probability tree reporting the cumulative probability of having gallstones for each combination of those symptoms and characteristics of pain significantly associated with gallstones. In conclusion, we have identified symptoms and signs significantly associated with gallstones. We have shown that there is an increase in frequency and severity of these symptoms and signs across the different stages of gallstone disease. We have proposed a complex of symptoms and signs significantly associated with gallstones that might help physicians in clinical decision making. (HEPATOLOGY 1999;30:839-846.)Despite the many efforts to delineate the clinical manifestations of gallbladder disease, the precise symptom complex associated with gallstones is still a matter of debate, and even the existence of gallstone-specific symptoms has been questioned. 1-3 Most of the attention has been focused on pain in gallstone patients, but there is no general agreement on its clinical meaning 3 and it is questioned whether pain occurs in gallstone disease with specific characteristics. 1,2 The identification of symptoms associated with this disease might help physicians in clinical decision making. [4][5][6][7] Moreover, the possibility of identifying patients who are more likely to have gallstones through a clinical assessment would limit the excessive and inappropriate use of di...