Outcomes and risk factors for complications in deletional haemoglobin H disease: A retrospective longitudinal cohort study in British Columbia, Canada
Bibliographic record
Abstract
To the Editor, Haemoglobin H (HbH) disease is the most common clinically significant form of αthalassaemia, primarily affecting populations in East and Southeast Asia, as well as the Mediterranean region.Due to global migration, however, HbH disease has become a worldwide health concern. 1 Despite its prevalence, research on the clinical outcomes of individuals with HbH disease, particularly those with the most common and presumed benign 'deletional' form, remains limited.Most published studies either fail to differentiate between genotypes or focus primarily on more severe non-deletional forms.Additionally, they are often constrained by retrospective or cross-sectional designs, focus on transfusion requirements or iron overload as their main outcomes or lack representation of older individuals.[2][3][4][5] Consequently, there is a paucity of high-quality data on thalassaemia-related mortality and morbidity associated with deletional HbH disease.6,7 To address this gap, we have conducted this retrospective longitudinal cohort study in British Columbia (BC), Canada, to examine thalassaemia-related mortality and morbidity in a cohort of patients with deletional HbH disease across the age spectrum.A secondary objective was to identify risk factors associated with the development of thalassaemia-related complications.Most patients with HbH disease in BC receive care at either St. Paul's Hospital or BC Children's Hospital in Vancouver.Patients were identified through provincial thalassaemia registries (the Inherited Coagulopathy and Haemoglobinopathy Information Portal and the BC Children's Thalassaemia Clinic database), covering the period from January 2010 to December 2023.Ethical approval was obtained from the University of British Columbia, with informed consent waived due to the study's retrospective nature.Figure S1 summarizes the inclusion and exclusion criteria and consolidated standards of reporting trials diagram for the study population.Data on clinical features, diagnostics, treatments and outcomes were collected from hospital records and the provincial electronic health record system (CareConnect).Accuracy of collected data was validated by auditing 20 random cases.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.006 |
| Science and technology studies | 0.004 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.003 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".