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Randomized trial · measured other health measures

Trial in 117 Tunisian adults with COVID-19: vitamin D lengthened time to negative test

Abroug and colleagues · Trials · 2023

Original title: Effect of vitamin D supplementation versus placebo on recovery delay among COVID-19 Tunisian patients: a randomized-controlled clinical trial.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

Points to harm

Median time until the virus test turned negative was 37 days with vitamin D vs 28 days with placebo (p=0.010). Hazard ratio was 1.58 (95% CI: 1.09-2.29, p=0.015).

The study at a glance

Type of study
Randomized trial
Who or what was studied
117 people · Adults in Tunisia with COVID-19 who still tested positive on day 14
What was tested
One dose of 200,000 IU vitamin D3 vs placebo (salt water)
What it measured
Other health or performance measures
Trial registration
NCT04883203
Who has a stake
No stake declared
No competing interests declared.
Journal
Trials, 2023
Source
PubMed record 36803273. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • ✓Compared with a placebo, a dummy treatment.
  • •Medium size: 117 people.
  • •Measured other health measures, not colds, flu and other respiratory infections itself.
  • ✓No competing interests declared.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: colds, flu and chest infections

    10

    2 benefit, 8 no difference

  2. Trials in people: other measures

    5

    1 benefit, 1 mixed, 2 no difference, 1 harm

    ↑ This study is the ringed dot

  3. Trials in people: lab tests or safety

    1

    1 no difference

  4. Population studies

    1

    1 no difference

  5. Blood levels and genes

    4

    3 benefit, 1 no difference

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does vitamin D prevent colds and infections?”

Not clearly; any effect looks small.

Confidence: low. Based on 33 on-topic papers.

Read the full answer

Of the other 4 papers on the same step: 1 benefit, 1 mixed, 2 no difference. This one found harm.

Other papers on the same step

See all 33 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The two reads agreed on every checked field. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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