Peter Muris
Peter Muris is a Dutch clinical psychologist, Professor of Clinical Psychological Science at Maastricht University, working on childhood anxiety, developmental psychopathology and the measurement of protective psychological traits. Outside that work he is best known for a standing methodological objection to Kristin Neff's Self-Compassion Scale, which he has pressed in a meta-analysis, a series of critical notes and a follow-up in 2022. He is making a measurement argument, it is a good one, and this site records both what it wins and what it does not.
Who they are
His post was confirmed on 11 September 2026 against the Maastricht University record.
The instrument at issue asks six kinds of question. Three are about kind responses to your own failure, and three are about harsh ones. The harsh answers are then flipped round, so that saying "no" to a harsh question adds to your self-compassion total.
Key papers
Muris, P., & Petrocchi, N. (2017). "Protection or vulnerability? A meta-analysis of the relations between the positive and negative components of self-compassion and psychopathology", Clinical Psychology and Psychotherapy, 24(2), 373 to 383. First published online in 2016. First author. The harsh items were tied considerably more strongly to mental health problems than the kind items were.
Muris, P., et al. (2018). "Good and bad sides of self-compassion: a face validity check of the Self-Compassion Scale", Journal of Child and Family Studies.
Muris, P., & Otgaar, H. (2022). "Deconstructing self-compassion: how the continued use of the total score of the Self-Compassion Scale hinders studying a protective construct", Mindfulness, 13, 1403 to 1409.
Key ideas
His case, at full strength, in one sentence. If you take a measure of self-criticism, reverse the scoring and call the result self-compassion, you have built distress into the measuring instrument, and the finding that self-compassion goes with better mental health is then guaranteed by the design rather than discovered by the research. A protective quality that dissolves the moment you stop reverse-scoring self-criticism is not a protective quality.
Neff's reply, also at full strength. Compassionate and uncompassionate responding are two ends of one thing rather than two separate things, so removing the harsh items removes half of what the word means. Her strongest evidence is an analysis across twenty samples and 11,685 people showing that a single general factor carries nearly all the reliable information in people's answers. And the point scoring cannot explain: when people are trained in the practice, the kind scores rise and the harsh scores fall at the same time, which is what one dimension does.
Where this site lands. The measurement objection stands, and anybody quoting the headline correlations should say that a large part of them is a questionnaire correlating with a near-copy of itself. The thing itself survives, because the treatment trials measure depression, stress and anxiety directly and so do not depend on the scoring argument at all.
His objection is not idiosyncratic. The same doubt, whether a self-critical trait adds anything beyond general emotional instability, arose independently in the clinical depression literature. Two fields arriving at the same worry is worth a sentence in any article that uses this construct.
Concepts on this site
Compassionate and Uncompassionate Self-Responding
Find them elsewhere
Nothing confirmed. A search was run and no website or account could be tied to this person with enough certainty to publish. A name match on its own is not evidence, and a wrong link here would be worse than none.
Checked 2026-09-11. Handles and affiliations go out of date, so treat this block as a snapshot rather than a standing fact.
Sources
- Muris, P., & Petrocchi, N. (2017). Clinical Psychology and Psychotherapy, 24(2), 373 to 383.
- Muris, P., et al. (2018). Journal of Child and Family Studies.
- Muris, P., & Otgaar, H. (2022). Mindfulness, 13, 1403 to 1409.
- Vault verification record, 2026-09-11. Affiliation confirmed against the Maastricht University Department of Clinical Psychological Science record. The self-compassion page was downgraded from a stronger evidence grade on the same date, partly because of this line of work.