{"id":"cd2fe586-0f78-5766-a052-155d076cd53f","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:cal-baron1999-adenomas","predicate":"has_reported_effect_on","statement":"Calcium carbonate reduced recurrent adenomas in the 1999 prevention trial.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"f31e7d98-9f8e-5c0d-a3f2-1064adf59510","mechanism_event_label":"One trial found fewer recurring colorectal polyps.","subject":{"id":"4ee1cbd0-1cec-58e1-9fee-bdb2c13db94d","slug":"calcium-carbonate","display_name":"Calcium carbonate","entity_type_key":"chemical_species"},"object":{"id":"4c47991c-d43e-542e-b061-839709a6c320","slug":"colorectal-adenoma-recurrence","display_name":"Colorectal adenoma recurrence","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"f31e7d98-9f8e-5c0d-a3f2-1064adf59510","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:cal-baron1999-adenomas-event","event_type":"observed_intervention","label":"One trial found fewer recurring colorectal polyps.","description":"Calcium carbonate reduced recurrent adenomas in the 1999 prevention trial.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"4ee1cbd0-1cec-58e1-9fee-bdb2c13db94d","slug":"calcium-carbonate","display_name":"Calcium carbonate","entity_type_key":"chemical_species"},"role":"tested_input","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4c47991c-d43e-542e-b061-839709a6c320","slug":"colorectal-adenoma-recurrence","display_name":"Colorectal adenoma recurrence","entity_type_key":"cellular_process"},"role":"measured_outcome","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Randomized post-polypectomy surveillance; 832 participants completed both examinations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Adjusted RR 0.81 (95% CI 0.67-0.99) between first and second surveillance examinations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Adenoma recurrence is distinct from colorectal-cancer incidence or mortality.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Calcium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"One trial found fewer recurring colorectal polyps.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[cal-clin-baron1999] Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group (1999). https://pubmed.ncbi.nlm.nih.gov/9887161/ DOI: 10.1056/NEJM199901143400204","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human clinical or absorption endpoint","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"637db785-7120-5acb-97e7-3b5529b2544b","evidence_kind":"source_excerpt","locator":"Lines 1305-1315","start_line":1305,"end_line":1315,"excerpt":"### cal-baron1999-adenomas\nCalcium carbonate reduced recurrent adenomas in the 1999 prevention trial.\nCondition category: normal\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: One trial found fewer recurring colorectal polyps.\norganism: Homo sapiens\ntissue_or_cell_type: Human clinical or absorption endpoint\nexperimental_model: Randomized post-polypectomy surveillance; 832 participants completed both examinations.\nlimitations: Adenoma recurrence is distinct from colorectal-cancer incidence or mortality.\nexposure: Adjusted RR 0.81 (95% CI 0.67-0.99) between first and second surveillance examinations.\n[cal-clin-baron1999] Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group (1999). https://pubmed.ncbi.nlm.nih.gov/9887161/ DOI: 10.1056/NEJM199901143400204","model_system":"Randomized post-polypectomy surveillance; 832 participants completed both examinations.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [cal-clin-baron1999] Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group (1999). https://pubmed.ncbi.nlm.nih.gov/9887161/ DOI: 10.1056/NEJM199901143400204","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"3c083fa0-59c6-50e9-af42-678d0e3c1006","stable_key":"import-434e1e27-eb90-583a-956b-62472726ffba","title":"Calcium: mechanism-first literature curation (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"965c934d6b147f2b62f8d45ce6d7a87681a600bfe5c46a585b4704889afd3fc1","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[{"id":"9b3f31bc-3920-525a-a56b-cffd03fd2368","title":"Adenoma recurrence findings were not consistent across trials","kind":"context_difference","status":"open","why":"Earlier and later trials differed in participants and treatment design. Overlapping confidence intervals and differing statistical significance alone do not prove contradictory biological effects. The discrepancy remains unexplained.","resolution":"Unresolved; needs review.","created_at":"2026-09-17 08:08:54","record_type":"conflict","display_label":"Recorded conflict","record_url":"/conflicts/9b3f31bc-3920-525a-a56b-cffd03fd2368","sides":[{"conflict_id":"9b3f31bc-3920-525a-a56b-cffd03fd2368","ordinal":0,"label":"One trial found fewer recurring colorectal polyps.","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","start_line":1305,"end_line":1315,"quote":"### cal-baron1999-adenomas\nCalcium carbonate reduced recurrent adenomas in the 1999 prevention trial.\nCondition category: normal\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: One trial found fewer recurring colorectal polyps.\norganism: Homo sapiens\ntissue_or_cell_type: Human clinical or absorption endpoint\nexperimental_model: Randomized post-polypectomy surveillance; 832 participants completed both examinations.\nlimitations: Adenoma recurrence is distinct from colorectal-cancer incidence or mortality.\nexposure: Adjusted RR 0.81 (95% CI 0.67-0.99) between first and second surveillance examinations.\n[cal-clin-baron1999] Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group (1999). https://pubmed.ncbi.nlm.nih.gov/9887161/ DOI: 10.1056/NEJM199901143400204","source_key":"import-434e1e27-eb90-583a-956b-62472726ffba","source_title":"Calcium: mechanism-first literature curation (2026-09-17)","claim_ids":["cd2fe586-0f78-5766-a052-155d076cd53f"]},{"conflict_id":"9b3f31bc-3920-525a-a56b-cffd03fd2368","ordinal":1,"label":"A later trial did not confirm the earlier polyp benefit.","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","start_line":1317,"end_line":1327,"quote":"### cal-baron2015-adenomas\nThe 2015 trial found no significant reduction in recurrent adenomas with assigned calcium.\nCondition category: normal\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A later trial did not confirm the earlier polyp benefit.\norganism: Homo sapiens\ntissue_or_cell_type: Human clinical or absorption endpoint\nexperimental_model: 2259 participants randomized in partial factorial design, 3-5-year follow-up.\nlimitations: Trial contexts differ; mechanism of between-trial disagreement remains unproven.\nexposure: 1200 mg calcium/day; calcium versus no-calcium adjusted RR 0.95 (95% CI 0.85-1.06).\n[cal-clin-baron2015] A Trial of Calcium and Vitamin D for the Prevention of Colorectal Adenomas (2015). https://pubmed.ncbi.nlm.nih.gov/26465985/ DOI: 10.1056/NEJMoa1500409","source_key":"import-434e1e27-eb90-583a-956b-62472726ffba","source_title":"Calcium: mechanism-first literature curation (2026-09-17)","claim_ids":["23736e09-47e8-5746-9b4f-d1fa42422687"]}]}],"corrections":[],"research":null}