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Open WellbeingWhat the studies actually measured

Sleep

Ironand Restless Legs Syndrome Severity

Both sources here measured lower restless Legs Syndrome Severity.

How sure anyone can be

Low certainty, level 2 of 4

Further research is likely to change this.

The most certain of the two findings here; each record carries its own.

The numbers reported

One source’s range, drawn against its own line of no difference and scaled to its own numbers.

-6.25-3.78-1.31

This range stays on one side of the no-difference line.

Bar the confidence interval — the range the true effect is likely to sit inNotch the number the source reportedLine where there would be no difference at all

Two sources, newest first

What we read is the published abstract, not the full paper, so a blank below may still be printed in the paper itself. A fixed rule worked this out from the source’s own fields. Nobody checked this rating by hand.

  • Systematic review, 2019 · 7 studies pooled · 345 participants

    Low certainty, level 2 of 4

    Iron for the treatment of restless legs syndrome.

    Cochrane Database Syst Rev. 2019;1(1):CD007834. doi:10.1002/14651858.CD007834.pub3. PMID:30609006.

    This source later carried a notice: Update of Cochrane Database Syst Rev. 2012 May 16;(5):CD007834. doi: 10.1002/14651858.CD007834.pub2. The number below is exactly as the source gave it.

    Number reported
    -3.78
    Which way it went
    Lower
    Likely range
    -6.25 to -1.31
    Source’s own words
    points on the International Restless Legs Scale (0-40), mean difference vs placebo
    Who was studied
    Adult with restless legs syndrome
    Compared with
    placebo
    Amount taken
    Not in the abstract
    For how long
    14 to 84 days
    Disagreement between studies
    I2= 66%
    Kind of record
    Journal article
    How this rating was reachedstarts at High, 2 steps down: imprecision and inconsistency
    1. Starts at High
    2. Imprecision brought it down to Moderate345 participants is below the 400-participant optimal information size floorReported in the abstract
    3. Inconsistency brought it down to Lowheterogeneity across pooled studies is high (I² = 66%)Reported in the abstract
    4. Ends at Low2 steps down.
    Checked, nothing to step it down for
    risk of bias and indirectness

    Imprecision stops at the first check that applies; others may apply too.

    AI-reviewed & signed — an AI agent re-read this finding against the saved source and checked that the quote, the numbers, the units and the direction match it. No person read it. The owner authorised the agent to sign the batch with the owner's key, and every build rechecks that signature against these exact bytes.

    Read the abstract on PubMed

  • Systematic review, 2019

    Low certainty, level 2 of 4

    Iron supplementation for restless legs syndrome - A systematic review and meta-analysis.

    Eur J Intern Med. 2019;63:34-41. doi:10.1016/j.ejim.2019.02.009. PMID:30798983.

    Number reported
    -3.55
    Which way it went
    Lower
    Likely range
    -5.41 to -1.68
    Source’s own words
    points on the International Restless Legs Scale, weighted mean difference vs no iron
    Who was studied
    Patients with RLS
    Compared with
    no iron
    Amount taken
    Not in the abstract
    For how long
    Not in the abstract
    Disagreement between studies
    Not in the abstract
    Kind of record
    Journal article
    How this rating was reachedstarts at High, 2 steps down: risk of bias and imprecision
    1. Starts at High
    2. Risk of bias brought it down to Moderatethe abstract reports no risk-of-bias or quality appraisal, so study limitations cannot be ruled outNot in the abstract
    3. Imprecision brought it down to Lowthe abstract does not state how many participants were pooledNot in the abstract
    4. Ends at Low2 steps down.
    Checked, nothing to step it down for
    indirectness
    Inconsistency
    No disagreement reported, and no count of studies behind it

    Imprecision stops at the first check that applies; others may apply too.

    Source saved; quote checked byte-for-byte against it by software; no signature.

    Read the abstract on PubMed

What is still missing from these readings

  • One do not say how many people took part.
  • Amount taken — Not in the abstract.
  • For how long — One of Two readings: Not in the abstract.

Something nobody wrote down is never a zero and never a guess.

Still to read for Iron

Eight of the 18 things on our list for Iron have no reading here yet:

  • Bloating Symptom Severity Score
  • Endurance Performance (Time to Exhaustion)
  • Fractional iron absorption
  • Heart rate variability (RMSSD)
  • Hematocrit
  • Serum iron
  • Soluble Transferrin Receptor (sTfR)
  • Total Iron Binding Capacity

Still to read means nobody here has got to it, not that it was tried and did nothing or that no research exists. A pairing on no list is not a gap: we never set out to read it.

Read next

  • Iron

    Nine other questions read for it

  • Sleep

    29 questions read under it

  • Restless Legs Syndrome Severity

    No other ingredients read against it

    Alphabetical, and by nothing else.

This is a library, not advice. No recommendation, no dose, no diagnosis, no ranking. We never ask about your symptoms, and nothing here is tailored to you.