Evidence map›Paper›PMID 32090730›Full record

Trial reportHealth technology assessment (Winchester, England)2020

High-dose oral vitamin D supplementation and mortality in people aged 65-84 years: the VIDAL cluster feasibility RCT of open versus double-blind individual randomisation.

Christine Rake, Clare Gilham, Laurette Bukasa, Richard Ostler, Michelle Newton, James Peto Wild, Benoit Aigret, Michael Hill, Oliver Gillie, Irwin Nazareth and 3 more

Open access · diamondAbstract readRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in Health technology assessment (Winchester, England), 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 7 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
15citing papers in PubMed, 7 pooled it
2.8field-weighted citation impact, top 9% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

15 citing papers in PubMed, 7 syntheses or guidelines pooled it, 32 citations in OpenAlex.

  1. Pooled it
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  14. Vitamin D Supplementation for Prevention of Type 2 Diabetes Mellitus: To D or Not to D?The Journal of clinical endocrinology and metabolism · 2020
    Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors at 7 institutions in 1 country.

Christine RakeDepartment of Non-communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
Clare GilhamDepartment of Non-communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
Laurette BukasaDepartment of Non-communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
Richard OstlerComputational and Analytical Sciences, Rothamsted Research, Harpenden, UK.
Michelle NewtonDepartment of Cardiovascular Sciences, University of Leicester, Leicester, UK.
James Peto WildDepartment of Non-communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
Benoit AigretBarts Clinical Trials Unit, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK.
Michael HillMedical Research Council Population Health Research Unit, University of Oxford, Oxford, UK.
Oliver GillieHealth Research Forum, London, UK.
Irwin NazarethDepartment of Primary Care and Population Health, University College London, London, UK.
Peter SasieniBarts Clinical Trials Unit, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK.
Adrian MartineauCentre for Primary Care and Public Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Julian PetoDepartment of Non-communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
London School of Hygiene & Tropical Medicine · GBQueen Mary University of London · GBRothamsted Research · GBUK Health Forum · GBUniversity College London · GBUniversity of Leicester · GBUniversity of Oxford · GB

Funding

Cancer Research UK 16893Cancer Research UK 25356Department of Health 08/116/48
6 · The paper itself

Abstract

backgroundRandomised controlled trials demonstrating improved longevity are needed to justify high-dose vitamin D supplementation for older populations.

objectivesTo demonstrate the feasibility of a large trial (

designTwenty GP practices were randomised in matched pairs between open-label and double-blind allocation. Within each practice, patients were individually randomised to vitamin D or control (i.e. no treatment or placebo). Participants were invited to attend their GP practice to provide a blood sample and complete a lifestyle questionnaire at recruitment and again at 2 years. Randomisation by telephone followed receipt of a serum corrected calcium assay confirming eligibility (< 2.65 nmol/l). Treatment compliance was reported by quarterly follow-up forms sent and returned by e-mail or post (participant choice). GP visits and infections were abstracted from GP records. Hospital attendances, cancer diagnoses and deaths were ascertained by linkage to Hospital Episode Statistics and national registration through NHS Digital.

settingGP practices in England.

participantsRecruitment opened in October 2013 and closed in January 2015. A total of 1615 registered patients aged 65-84 years were randomised: 407 to vitamin D and 421 to no treatment in open practices; 395 to vitamin D and 392 to placebo in blind practices.

interventionsThere was a 24-month treatment period: 12 monthly doses (100,000 IU of vitamin D

main outcome measuresRecruitment, compliance, contamination and change in circulating 25-hydroxyvitamin D [25(OH)D] from baseline to 2 years.

resultsParticipation rates (randomised/invited) were 15.0% in open practices and 13.4% in double-blind practices (

conclusionsA trial could recruit 20,000 participants aged 65-84 years through 200 GP practices over 2 years. Approximately 80% would be expected to adhere to allocated treatment (vitamin D or placebo) for 5 years. The trial could be conducted entirely by e-mail in participants aged < 80 years, but some participants aged 80-84 years would require postal follow-up. Recruitment and treatment compliance would be similar and contamination (self-administration of vitamin D) would be minimal, whether control participants are randomised openly to no treatment with no contact during the trial or randomised double-blind to placebo with monthly reminders.

trial registrationCurrent Controlled Trials ISRCTN46328341 and EudraCT database 2011-003699-34.

fundingThis project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in

Indexed as

Dietary SupplementsGeneral PractitionersMortalityPatient ComplianceAgedAged, 80 and overDouble-Blind MethodFeasibility StudiesFemaleHumansMaleSurveys and QuestionnairesUnited KingdomVitamin DVitamin DCLUSTER RANDOMISATIONFEASIBILITYGP PRACTICERANDOMISED TRIALVITAMIN D

Identifiers

PMID32090730
PMCPMC7061272
OpenAlexW3008812804

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.