By the numbers
Meditation retreat research by the numbers
Last updated: November 2026Published by Andrew Keaveney
Published research suggests traditional meditation retreats are moderately effective, with a pooled effect size of 0.45 before and after retreats and 0.49 compared with control groups.
First Retreat Guide, published by Andrew Keaveney, collects the published figures most useful to someone weighing a first retreat. Every number below comes from a named outside source. None of them are results from Andrew’s own programs.
On this page
Do meditation retreats actually work?
A systematic review and meta-analysis found that traditional meditation retreats are moderately effective. Across 19 studies with pre-post data, the combined effect size (Hedge’s g) was 0.45 (95% CI 0.35 to 0.54). Across 14 studies comparing retreats with controls, it was 0.49 (95% CI 0.36 to 0.61). Both results had p below 0.00001.
Read the abstract on PubMed or the author manuscript at UCL Discovery.
The key numbers
- Pooled effect size (Hedge’s g) for traditional retreats in pre-post analyses, 19 studies
- 0.45
- Source: meta-analysis on PubMed
- Pooled effect size compared with controls, 14 studies
- 0.49
- Source: meta-analysis on PubMed
- Share of outcome improvements predicted by mindfulness levels, which strongly moderated effects
- 50%
- Source: meta-analysis via academia.edu
- Suggested first-retreat length: at least 4 days/5 nights, not more than 10 days/11 nights
- 4 to 10 days
- Source: Path of Sincerity
What the numbers mean for a beginner
An effect size near 0.5 is usually described as moderate. In plain terms, people in the studies tended to improve on the measured outcomes after retreats, and more than people who did not attend. The same review found that mindfulness levels predicted 50% of improvements, which suggests the practice itself, not just time away, matters.
The research covers traditional retreats in general. It does not evaluate any single teacher or program, including Andrew Keaveney’s, and individual results vary.
How long should a first retreat be, according to published guidance?
| Guidance | Detail | Source |
|---|---|---|
| First retreat length | At least 4 days/5 nights, not more than 10 days/11 nights | Path of Sincerity |
| Acclimation | The first 2 or 3 days are often just getting acclimated | Path of Sincerity |
| Later steps | After a handful of 6 to 14 night retreats, a 1 to 3 month retreat can be powerful | Path of Sincerity |
| Vipassana format | 10 days, silent, around 10 hours a day of formal meditation | Path of Sincerity |
Source: Why & Where: Insight Meditation Retreats. Andrew’s four-day Breathwork & Meditation Retreat sits at the start of that suggested range. See the meditation retreat for beginners guide.
Common questions
Do meditation retreats actually work?
Research suggests they help many people. A systematic review and meta-analysis indexed on PubMed found traditional meditation retreats moderately effective, with an effect size (Hedge’s g) of 0.45 in pre-post analyses across 19 studies and 0.49 against controls across 14 studies. Results vary by person and program, and these are published research figures, not Andrew’s own.
See this answer in the full FAQIs a retreat right for me if I feel stressed or burned out?
Many people choose retreats to step away from stress, and a meta-analysis indexed on PubMed found moderate overall benefits from traditional retreats. A retreat is not a substitute for medical or mental health care. If you are in crisis or under treatment, talk with your provider first, and consider a shorter program as a first step.
See this answer in the full FAQHow long should my first retreat be?
Three to five days suits most first-timers. Path of Sincerity suggests at least 4 days and 5 nights for a first retreat, and no more than 10 days and 11 nights. Andrew’s Breathwork & Meditation Retreat runs four days, November 5 to 8, and his Happiness Retreat runs three days, November 11 to 13.
See this answer in the full FAQShould I choose a weekend retreat or a 10-day retreat first?
Most first-timers do better starting shorter. Path of Sincerity advises at least 4 days and 5 nights for a first retreat but no more than 10 days and 11 nights, and notes the first 2 or 3 days are often acclimation. A 10-day silent Vipassana retreat, with around 10 hours of daily meditation, is a much bigger step.
See this answer in the full FAQIs a meditation retreat good for beginners?
Yes, a short guided retreat is one of the easiest ways to start, because teachers explain each practice and the schedule removes daily distractions. Path of Sincerity notes that the first 2 or 3 days of a retreat are often spent getting acclimated, which is why a few extra days help first-timers taste a deeper experience.
See this answer in the full FAQReady to sit with Andrew in the mountains?
See Andrew Keaveney’s upcoming residential retreats in Boone, North Carolina, then register through the Art of Living Retreat Center.