Trial reportTrials2016
Recruitment and representativeness of blood donors in the INTERVAL randomised trial assessing varying inter-donation intervals.
Trial report in Trials, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Identification of novel risk loci for restless legs syndrome in genome-wide association studies in individuals of European ancestry: a meta-analysis.The Lancet. Neurology · 2017Pooled it
- Cost-effectiveness of alternative minimum recall intervals between whole blood donations.PloS one · 2022Trial
- Longer-term efficiency and safety of increasing the frequency of whole blood donation (INTERVAL): extension study of a randomised trial of 20 757 blood donors.The Lancet. Haematology · 2019Trial
- Efficiency and safety of varying the frequency of whole blood donation (INTERVAL): a randomised trial of 45 000 donors.Lancet (London, England) · 2017Trial
- Article
- Representativeness of the Danish Blood Donor Study relative to the general population: a cross-sectional assessment.Scientific reports · 2026Article
- Role of pain and anxiety in mediating relationships between donation history and vasovagal reaction symptoms in blood donors in England.Transfusion · 2026Article
- Improved genetic discovery and fine-mapping resolution through multivariate latent factor analysis of high-dimensional traits.Cell genomics · 2025Article
- Optimal individualized decision rules from a multi-arm trial: A comparison of methods and an application to tailoring inter-donation intervals among blood donors in the UK.Statistical methods in medical research · 2020Article
- Article
- Somatic mosaicism and common genetic variation contribute to the risk of very-early-onset inflammatory bowel disease.Nature communications · 2020Article
- Blood, sweat, and tears: Red Blood Cell-Omics study objectives, design, and recruitment activities.Transfusion · 2019Article
- Methodology and cohort profile for the Hangzhou Lumbar Spine Study: a study focusing on back health in a Chinese population.Journal of Zhejiang University. Science. B · 2018Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
15 authors.
Funding
Abstract
backgroundThe interpretation of trial results can be helped by understanding how generalisable they are to the target population for which inferences are intended. INTERVAL, a large pragmatic randomised trial of blood donors in England, is assessing the effectiveness and safety of reducing inter-donation intervals. The trial recruited mainly from the blood service's static centres, which collect only about 10 % of whole-blood donations. Hence, the extent to which the trial's participants are representative of the general blood donor population is uncertain. We compare these groups in detail.
methodsWe present the CONSORT flowchart from participant invitation to randomisation in INTERVAL. We compare the characteristics of those eligible and consenting to participate in INTERVAL with the general donor population, using the national blood supply 'PULSE' database for the period of recruitment. We compare the characteristics of specific groups of trial participants recruited from different sources, as well as those who were randomised versus those not randomised.
resultsFrom a total of 540,459 invitations, 48,725 donors were eligible and consented to participate in INTERVAL. The proportion of such donors varied from 1-22 % depending on the source of recruitment. The characteristics of those consenting were similar to those of the general population of 1.3 million donors in terms of ethnicity, blood group distribution and recent deferral rates from blood donation due to low haemoglobin. However, INTERVAL participants included more men (50 % versus 44 %), were slightly older (mean age 43.1 versus 42.3 years), included fewer new donors (3 % versus 22 %) and had given more donations over the previous 2 years (mean 3.3 versus 2.2) than the general donor population. Of the consenting participants, 45,263 (93 %) donors were randomised. Compared to those not randomised, the randomised donors showed qualitatively similar differences to those described above.
conclusionsThere was broad similarity of participants in INTERVAL with the general blood donor population of England, notwithstanding some differences in age, sex and donation history. Any heterogeneity of the trial's results according to these characteristics will need to be studied to ensure its generalisability to the general donor population.
trial registrationCurrent Controlled Trials ISRCTN24760606 . Registered on 25 January 2012.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.