Comment by rahimnathwani

This is marked on the page as an 'Original Investigation', but right below the title it says it's a 'Systematic Review and Meta-Analysis'.

I'm skeptical about meta analyses in general because, the times when I've dug into a meta analysis and traced the conclusions back to the original papers, I've always been disappointed, and ended up not being convinced of the conclusions of the meta analysis.

Anyway, I haven't done that exercise for this paper, but I will say:

- Although the authors say they did a "systematic review and meta-analysis of 19 studies", only 12 of the 19 papers are included in the meta analysis.

- Only one of the authors read all the studies they included ("Study quality was assessed by 1 reviewer.")

- That reviewer was Lucy Corrigan, BSc ("Full texts were screened (L.C.) against the same inclusion and exclusion criteria (165 articles)...")

Here is the abstract of one of the 12 studies they included (and marked as 'Good' quality, the highest rating they gave): https://www.tandfonline.com/doi/full/10.1080/19485565.2021.2...

Here is what they found:

  Discrete-time hazard analysis indicates that the log odds of mortality were significantly lower among 18 and 19 year old adults ever diagnosed with ADHD and significantly higher among 46 to 64 year old adults ever diagnosed with ADHD, with a crossover occurring at age 33.