g = 0.45
Retreats, before and after
Traditional meditation retreats were moderately effective in pre-post analyses (n=19; Hedge’s g=0.45; 95% CI [0.35, 0.54], p<0.00001).
By the numbers
Meditation retreats by the numbers
Last updated November 2026By Andrew Keaveney
Published research finds traditional meditation retreats moderately effective, with an effect size of g=0.45 before and after and g=0.49 compared to controls.
This page, part of Andrew Keaveney's retreat guide, collects published statistics on meditation retreats and everyday practice, each quoted exactly as published with its range and source. These are findings from outside research, not Andrew's own figures or a promise of any individual result.
Do meditation retreats actually work?
According to a systematic review and meta-analysis, traditional meditation retreats are moderately effective. Across 19 studies with pre-post data, the combined effect was g=0.45 (95% CI [0.35, 0.54]), and across 14 studies with control groups it was g=0.49 (95% CI [0.36, 0.61]). Results vary by person and program.
Published meditation retreat statistics
g = 0.49
Retreats compared to controls
In analyses comparing retreats to controls, the effect was also moderate (n=14; Hedge’s g=0.49; 95% CI [0.36, 0.61], p<0.00001).
50%
The role of mindfulness
Mindfulness levels strongly moderated clinical effect sizes, predicting 50% of improvements in outcomes.
Source: Khoury et al., via Academia.edu
61.6%
Daily practice
Most practitioners (61.6%) meditate daily.
Source: 2026 Meditation Practice Report, Mindful Leader (May 12, 2026)
36.2%
Typical session length
10 to 20 minutes is the most common session length (36.2%).
Source: 2026 Meditation Practice Report, Mindful Leader (May 12, 2026)
What these numbers mean for choosing a retreat
Definition: effect size (Hedge's g)
Hedge's g is a standardized measure of how large a change is, used to combine results from many studies. Values around 0.5 are commonly described as moderate. The 95% confidence interval shows the range the true effect likely falls in: for retreats compared to controls, 0.36 to 0.61. The full paper is available from UCL Discovery.
A practical reading
Two takeaways are useful for anyone considering a retreat. First, the research found retreats helped on average, not in every case. Second, mindfulness levels predicted half of the improvement, which suggests the practice itself matters more than the setting. That is why Andrew Keaveney's retreats focus on giving you a breathwork and meditation routine you can continue at home, in line with the 10 to 20 minute sessions most practitioners report.
Part of the meditation retreat guide by Andrew Keaveney.
Research questions
Do meditation retreats actually work?
Published research suggests they can help. A systematic review and meta-analysis by Khoury and colleagues found traditional meditation retreats moderately effective in pre-post analyses (n=19; Hedge’s g=0.45; 95% CI [0.35, 0.54]) and compared to controls (n=14; Hedge’s g=0.49; 95% CI [0.36, 0.61]). Individual results vary, and a retreat is not a substitute for medical care.
More in the full FAQ: Do meditation retreats actually work?How is a retreat different from a weekly meditation class?
A weekly class fits practice into normal life, while a retreat removes normal life for several days so practice can deepen without interruption. Retreats give you repeated sessions in a row, guidance from a teacher on site, and a supportive setting. Many people use a retreat to start or reset a practice they then continue at home.
More in the full FAQ: How is a retreat different from a weekly meditation class?Is a meditation app enough, or do I need a retreat?
An app is a convenient way to build a daily habit, and a 2026 Mindful Leader report found 61.6% of practitioners meditate daily. A retreat adds what an app cannot: a teacher in the room, consecutive days of practice and time away from routine. Many people use both, with the retreat deepening the daily practice.
More in the full FAQ: Is a meditation app enough, or do I need a retreat?What are common myths beginners believe about meditation?
Common myths include needing an empty mind, needing to sit cross-legged for hours, and needing years of practice before benefiting. Andrew Keaveney addresses these in his short film Biggest Meditation Myths Busted. Most teachers treat wandering thoughts as part of the practice, not a failure, and offer seated options that suit different bodies.
More in the full FAQ: What are common myths beginners believe about meditation?Is every meditation retreat a silent meditation retreat?
No. Some retreats keep silence for most or all of the program, while others include talking, group sharing and teaching. Formats differ by tradition and teacher. If silence matters to you, either because you want it or want to avoid it, read the program description closely or ask the organizer before booking a specific retreat.
More in the full FAQ: Is every meditation retreat a silent meditation retreat?Put the research into practice
Learn breathwork and meditation in person at a residential retreat with Andrew Keaveney.