{"id":"f892a55b-fbe2-5a2e-851c-5581607c93cf","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iod-clin-preconception-neurology","predicate":"preconception-administration-reduces","statement":"Among children conceived after maternal trial entry, the follow-up classified 0 of 237 in the iodinated-oil group and 14 of 215 in the saline group as definite cases of the historical neurological iodine-deficiency syndrome.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"79122634-310f-50e4-86bf-9268ea984fe7","mechanism_event_label":"In severe deficiency, supplying iodine before conception prevented the study-defined definite neurological syndrome in this follow-up.","subject":{"id":"a6c8a491-944e-5f9a-9caf-6e9063b9030f","slug":"iodized-oil","display_name":"Iodized oil preparation","entity_type_key":"chemical_species"},"object":{"id":"f4b63265-5b48-53dd-9be2-a7c0bbcafcfb","slug":"severe-prenatal-iodine-neurological-syndrome","display_name":"Severe prenatal iodine-deficiency neurological syndrome","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"79122634-310f-50e4-86bf-9268ea984fe7","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iod-clin-preconception-neurology-event","event_type":"observed_intervention","label":"In severe deficiency, supplying iodine before conception prevented the study-defined definite neurological syndrome in this follow-up.","description":"Among children conceived after maternal trial entry, the follow-up classified 0 of 237 in the iodinated-oil group and 14 of 215 in the saline group as definite cases of the historical neurological iodine-deficiency syndrome.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0e0ac6d1-3336-506a-9f69-5838ca1500ed","slug":"iodine","display_name":"Iodine","entity_type_key":"nutrient_element"},"role":"maternal repletion","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"a6c8a491-944e-5f9a-9caf-6e9063b9030f","slug":"iodized-oil","display_name":"Iodized oil preparation","entity_type_key":"chemical_species"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"f4b63265-5b48-53dd-9be2-a7c0bbcafcfb","slug":"severe-prenatal-iodine-neurological-syndrome","display_name":"Severe prenatal iodine-deficiency neurological syndrome","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Primary PDF Methods p.69, Results and Fig2 pp.70–71; relevant pages visually inspected because OCR is imperfect.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Historical double-blind controlled maternal iodinated-oil trial begun 1966, with children born 1966–1972 followed through 1982 in five selected Papua New Guinea villages","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Intramuscular iodinated oil versus saline; comparison by conception before/after maternal trial entry. The follow-up paper does not verify the injection dose in the inspected methods.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Long-term follow-up was restricted for logistical reasons to five of 13 original villages with high disease prevalence. Historical syndrome criteria and selection differ from modern mild-deficiency trials. Do not assume all developmental disorders were prevented or that established deficits were reversed. Two possible cases remained among the 237 treated-group children. Three definite treated-group cases in the overall 274 children had maternal treatment only at 30, 32 or 34 weeks gestation; this does not establish an exact universal gestational cutoff.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Iodine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"iodine","display_name":"Iodine","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"In severe deficiency, supplying iodine before conception prevented the study-defined definite neurological syndrome in this follow-up.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iod-clin-pharoah1987] A controlled trial of iodinated oil for the prevention of endemic cretinism: a long-term follow-up. (1987). https://pubmed.ncbi.nlm.nih.gov/3032814/ DOI: 10.1093/ije/16.1.68","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Child neurological, hearing/speech and motor outcomes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"67db7eaa-ec9e-511a-acb6-c6d41422779f","evidence_kind":"source_excerpt","locator":"Lines 1412-1424","start_line":1412,"end_line":1424,"excerpt":"### iod-clin-preconception-neurology\nAmong children conceived after maternal trial entry, the follow-up classified 0 of 237 in the iodinated-oil group and 14 of 215 in the saline group as definite cases of the historical neurological iodine-deficiency syndrome.\nCondition category: nutrient_deficiency\nnutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: In severe deficiency, supplying iodine before conception prevented the study-defined definite neurological syndrome in this follow-up.\norganism: Homo sapiens\ntissue_or_cell_type: Child neurological, hearing/speech and motor outcomes\nexperimental_model: Historical double-blind controlled maternal iodinated-oil trial begun 1966, with children born 1966–1972 followed through 1982 in five selected Papua New Guinea villages\nlimitations: Long-term follow-up was restricted for logistical reasons to five of 13 original villages with high disease prevalence. Historical syndrome criteria and selection differ from modern mild-deficiency trials. Do not assume all developmental disorders were prevented or that established deficits were reversed. Two possible cases remained among the 237 treated-group children. Three definite treated-group cases in the overall 274 children had maternal treatment only at 30, 32 or 34 weeks gestation; this does not establish an exact universal gestational cutoff.\nexposure: Intramuscular iodinated oil versus saline; comparison by conception before/after maternal trial entry. The follow-up paper does not verify the injection dose in the inspected methods.\ncross_nutrient: false\nevidence_location: Primary PDF Methods p.69, Results and Fig2 pp.70–71; relevant pages visually inspected because OCR is imperfect.\n[iod-clin-pharoah1987] A controlled trial of iodinated oil for the prevention of endemic cretinism: a long-term follow-up. (1987). https://pubmed.ncbi.nlm.nih.gov/3032814/ DOI: 10.1093/ije/16.1.68","model_system":"Historical double-blind controlled maternal iodinated-oil trial begun 1966, with children born 1966–1972 followed through 1982 in five selected Papua New Guinea villages","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [iod-clin-pharoah1987] A controlled trial of iodinated oil for the prevention of endemic cretinism: a long-term follow-up. (1987). https://pubmed.ncbi.nlm.nih.gov/3032814/ DOI: 10.1093/ije/16.1.68","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"76da623d-a34a-5a5c-a942-d7571a85c486","stable_key":"import-aaa7baba-8689-56ab-ba1e-b71542bcb8e9","title":"Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (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":"a4885eb6f58bad4a4514c958b63834619e57b10aa7f694aa97d0f65c7d36548f","revision_id":"ea8001a1-b576-5eda-a193-883c7ad59b73","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}