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Pooled review (meta-analysis)

Pooled review of 154 trials in adults with insomnia: no clear overall melatonin benefit

De Crescenzo and colleagues · Lancet (London, England) · 2022

Original title: Comparative effects of pharmacological interventions for the acute and long-term management of insomnia disorder in adults: a systematic review and network meta-analysis.

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

No difference

Melatonin did not show overall material benefits. Benzodiazepines, eszopiclone, zolpidem and zopiclone were more efficacious than melatonin, ramelteon and zaleplon (SMD 0·27-0·71).

The study at a glance

Type of study
Pooled review (meta-analysis)
Who or what was studied
154 studies, 44,089 people · adults with insomnia disorder
What was tested
30 sleep drugs including melatonin, compared with placebo and each other; short-term and long-term use
What it measured
Several kinds of outcomes
Who has a stake
Company stake
Some authors report fees from Angelini Pharma, Lundbeck-supplied melatonin for another trial, and Janssen trials; one is a Boehringer Ingelheim employee.
Journal
Lancet (London, England), 2022
Source
PubMed record 35843245. This page is based on the abstract only.

How much this study counts

  • ✓Pools the results of 154 studies with 44,089 people.
  • •A pooled review is only as strong as the studies it pools.
  • •Measured several kinds of outcomes.
  • –Company stake: Some authors report fees from Angelini Pharma, Lundbeck-supplied melatonin for another trial, and Janssen trials; one is a Boehringer Ingelheim employee.
  • •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

This paper is not on the ladder. It is a pooled review (meta-analysis), and reviews and opinion pieces discuss studies that are already counted on the steps below.

↑ Stronger evidence

  1. Trials in people: sleep onset and sleep quality

    8

    2 benefit, 2 mixed, 4 no difference

  2. Trials in people: other measures

    2

    1 benefit, 1 no difference

  3. Trials in people: lab tests or safety

    0

    None among the papers we read.

  4. Population studies

    0

    None among the papers we read.

  5. Blood levels and genes

    0

    None among the papers we read.

↓ 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 melatonin help you sleep?”

A small effect, clearer in children.

Confidence: low. Based on 20 on-topic papers.

Read the full answer
  • Part of the finding “Adults with insomnia: reviews disagree on any benefit”.
  • Summed up in “What reviews found”: Pooled 154 double-blind trials (44 089 people) of 30 insomnia drugs in adults. Melatonin, ramelteon and unlicensed drugs did not show overall material benefits; several sleeping pills worked better than melatonin.
  • Marked as a key paper in the research timeline: Largest review: no material benefit in adult insomnia.

Other reviews on this question

See all 20 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 differed. The reviewer checked the abstract and kept the first read. 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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