Research
What the Maastricht study says about IEMT — read from practice
Since March 2026 there is, for the first time, peer-reviewed lab research directly comparing IEMT and EMDR. For practitioners who use the method or are considering learning it: what the research does ground, what it does not, and what it says about how you position IEMT in your own practice.
Design
What the Maastricht study measures exactly
The Maastricht study is a lab comparison with thirty-three participants from the general population. It is a within-subject design: every participant underwent all three conditions — IEMT, EMDR and a control condition (twenty minutes sitting in silence). The three conditions were coupled to three self-chosen negative memories, distributed blinded across the conditions. Main outcome: the SUD score (Subjective Units of Distress, a visual-analogue scale from 0–100 for experienced emotional charge). Measurements before the session, directly after, and one week later.
What this design does measure: whether a short IEMT condition and a short EMDR condition both give a larger SUD reduction than sitting quietly. And whether those two conditions differ from each other on that measure. What this design does not measure: full session effects of the IEMT or EMDR protocol, clinical working with PTSD or anxiety disorders, or the working of the identity work that characterises the technique frame of IEMT. It is a rigorous comparison of the eye-movement component — no more and no less.
Findings
The numbers, briefly
- SUD reduction IEMT: 43 points (Cohen’s dz 1.82) — classified as “very large” in the scientific literature.
- SUD reduction EMDR: 44 points (Cohen’s dz 1.86) — also “very large”.
- SUD reduction control: 19 points (Cohen’s dz 0.72) — medium-large.
- IEMT and EMDR statistically no different on SUD reduction. Both significantly better than the control condition.
- Effect retained at follow-up one week later — for both conditions, also in this non-clinical population.
- On the DASS-21-R (a standardised questionnaire for stress, anxiety and depression) participants scored lower a week later on average for stress (−2.1 points) and depressive complaints (−3.0 points). For anxiety no significant effect. The authors are cautious about this: the sample was already within the normal range.
What this confirms for your practice
Three observations practitioners recognise, now lab-grounded
If you work with IEMT in your practice, there are three things you probably see happening already. This study confirms them within the limits of a lab design — and it is precisely those limits that make the confirmation interesting.
1. Effect within one short working unit is real.
Twenty minutes of targeted eye-movement work with a negative memory gives a measurable drop in subjective charge. No build-up session, no rapport building, no ritual opening — working briefly on a specific target shows a shift. For those used to longer talking modalities this may still feel counterintuitive; for those already working with IEMT it matches what you encounter.
2. The difference from “just sitting” is robust.
The control condition also showed a drop (19 points), which you would expect: giving attention to a memory often calms something already. But the drop with the IEMT or EMDR condition was more than twice as large. What you do matters; it is not only being present or regression to the mean.
3. The effect holds.
At the measurement one week later, the drop had not bounced back. In a non-clinical population, without follow-up sessions. For the work with clients this is the anchor for the honest question “does it keep working?” — the study gives that question a factual answer within the scope of what it measures.
Important: all of this on a twenty-minute fragment of what IEMT does as a method. It says something about the eye-movement layer, not about the identity work and the pattern layer the method works on besides. For those layers the grounding is methodical, not experimental — and that methodical anchoring runs via Austin’s own lineage (Grove, Andreas) and the UK Association canon.
The client preference
Why 60.6% chose IEMT blinded — and what that means for your work
Because every participant underwent all three conditions without knowing which-was-which, they could state their preference at the end without the bias of name recognition. Twenty of the thirty-three participants (60.6%) chose IEMT, nine chose EMDR (27.3%), four had no preference (12.1%).
The reasons participants themselves gave for their IEMT preference (named more than once):
- A calmer, gentler, more emotional perspective (10×)
- More insight, depth and synthesis through an all-encompassing character (10×)
- The eye movements were more pleasant (5×)
- No need to talk (4×)
- More intense, but felt more effective (4×)
- No headache, no tired eyes (4×)
For your practice, two of these are especially operationally relevant. No need to talk is, for many clients, the practical lowering of the threshold: people who have already told earlier talking courses at length what is at play do not have to do so again here. For those reluctant to share personal details with a new coach, that is a real opening. Fewer physical side effects — no headache, less tired eyes — make it deployable for clients who come to a session within a working day and have to get back to work in the afternoon.
What the preference does not mean: that IEMT is “better” than EMDR. On the SUD measure they were statistically equal. The preference is about the experience — and that experience is relevant for the work, but not the same as effect.
What this study does not do
The limitations — and what that means for your positioning
The authors name the limitations explicitly and clearly. For practitioners they are not just an academic footnote but the anchor for how you can position IEMT honestly — to clients, to referrers, to commissioners.
- Small and non-clinical sample. N = 33, general population, no diagnosis. This is exploratory lab work, not large-scale clinical evidence.
- Twenty minutes per condition. The full IEMT protocol takes longer and works on more layers than the eye-movement component alone. The study compares eye-movement conditions, not the whole method.
- No active working-memory control task (for example Tetris). It therefore cannot be firmly excluded that the effect is partly due to working-memory load in a broad sense, rather than specifically to the eye-movement structure.
- Generalisability to clinical groups unclear. PTSD, anxiety disorders, depression — the working on those populations cannot be established on the basis of this study.
- Neuro-mechanisms not measured. What happens in the brain to explain this effect remains unanswered; the authors recommend EEG and MRI follow-up research.
What this means for your positioning: the study grounds IEMT as a coaching anchor with non-clinical working questions — self-image, recurring relational triggers, ingrained reaction patterns, a light trauma trace in a stable context. It is no mandate for PTSD treatment or clinical diagnostics; there the clinical basis remains leading and referral to regulated healthcare professionals belongs. Honesty about that strengthens the credibility — with clients, with referrers, with yourself.
The broader evidence context: before the Maastricht publication there was no direct IEMT RCT. The research field consisted of indirect support — meta-analyses of eye movements in emotional memory processing, the extensive EMDR evidence base (partly overlapping, partly non-transferable), and smaller studies on eye movements and attention/decision-making. The IEMT canon explicitly positions itself as a practice-based profession: methodically founded on clinical observations of practitioners and trainers, not as a bounded scientific discipline. The Maastricht study does not shift that — IEMT remains practice-based — but it adds a first, peer-reviewed lab anchor where previously there was only indirect evidence and practice observation.
The frame
UK Association canon: complement, not replace
The Association for IEMT Practitioners — the international accreditation body that Andrew T. Austin founded in 2015 — formulates the working frame this way:
“IEMT practitioners are committed to enhancing well-being without making unwarranted claims about treating medical or psychiatric conditions.”
“IEMT is designed to complement, not replace, conventional treatments.”
The Maastricht study fits within this frame. It shows what the eye-movement component of IEMT can do in an experimental setting, and makes no statement about what it has not investigated. For practitioners that is the workable position: deploy IEMT where it fits, refer where it does not, and be honest about the difference.
The same research, a different lens
Written for clients
Anyone who wants to share this research with a client, a commissioner or an HR department will find a parallel piece on iemtcoaching.com from the client or HR position. Two tabs: one for HR and managers, one for professionals considering working with a coach themselves. Same data, different entry.
Want to learn to apply this yourself?
You do not learn IEMT by reading about research. A Practitioner training works on skill in your own practice — with the time, practice, supervision and feedback that go with it. How I set up that training follows the training DNA I carry under all work modalities: safety, craft, service and productive tension. No overclaim, no superlatives.
For those who want to read the broader method picture, the hub holds six elaborating pieces — from definition to session experience.
Frequently asked questions
Briefly answered
What does the Maastricht study 2026 measure about IEMT?
The Maastricht study is a lab comparison with thirty-three participants from the general population, randomised across three conditions (IEMT, EMDR and a control condition of twenty minutes sitting in silence). The main outcome is the SUD score (Subjective Units of Distress) on self-chosen negative memories, measured before, directly after and one week after the session. It measures the eye-movement component of IEMT, not the full protocol.
How large is the IEMT effect in the study?
A SUD reduction of 43 points for IEMT (Cohen's dz 1.82, "very large" effect), 44 points for EMDR (dz 1.86, also "very large"), and 19 points for the control condition (dz 0.72, medium-large). IEMT and EMDR are statistically no different from each other; both significantly better than control. The effect was retained at a follow-up one week later.
What does the study say about IEMT vs EMDR?
On the SUD measure, IEMT and EMDR are statistically equal. Blinded across the conditions, 60.6% of participants chose IEMT as their preference, 27.3% chose EMDR and 12.1% had no preference. Reasons for IEMT preference named more than once: a calmer and gentler perspective, more insight and synthesis, less headache and tired eyes, no need to talk about the memory. The preference is about the experience, not about effect.
What are the limitations of this study?
Small and non-clinical sample (N = 33, general population, no diagnosis). Twenty minutes per condition — the full IEMT protocol takes longer and works on more layers. No active working-memory control task. Generalisability to PTSD, anxiety disorders or depression cannot be established on this basis. Neuro-mechanisms not measured; EEG and MRI follow-up research recommended by the authors.