Systematic review
A study that searches for every good trial on one question and weighs them together, instead of picking favourites. It is only as strong as the trials inside it.
What does systematic review mean?
Systematic review: A study that searches for every good trial on one question and weighs them together, instead of picking favourites. It is only as strong as the trials inside it.
How it is used in the Splash library
A 2020 systematic review and meta-analysis pooled many studies on exercise performance across the cycle.
From “Cycle syncing: an evidence check”A 2024 systematic review of 41 studies found that most reported a link between psychological stress and irregular cycles, though the way studies measured both varied a lot.
From “How stress, travel and illness affect your cycle”A 2025 systematic review of 11 studies found the evidence was suggestive that ADHD symptoms change with hormones, including across the menstrual cycle.
From “ADHD and your cycle”A 2025 Systematic review of 31 trials agreed: some supplements looked helpful, but only 1 of the 31 trials was at low risk of bias.
From “PMS supplements: what the evidence says”
Where it comes up
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