How do you test a healing practice that works with "healing fluids" using the tools of clinical medicine? In 2016 a Brazilian research group around Ricardo de Souza Cavalcante at the Universidade Estadual Paulista (UNESP) attempted exactly that: they subjected the Spiritist passe — the laying on of hands — to a randomised, sham-controlled trial design. The result is cautiously positive and, at the same time, an instructive example of where such studies reach their limits.
What is the passe?
The passe is one of the central healing practices of Brazilian Spiritism. A trained "passista" holds their hands over or near the recipient's body and, in Kardecist self-understanding, transmits "healing fluids" — a vital energy meant to restore the patient's disturbed balance. Phenomenologically this resembles Reiki or the "therapeutic touch" of nursing science, but it is theoretically anchored in the doctrine of Allan Kardec. In Brazil's spiritist hospitals the passe is a fixed part of the complementary spiritual therapy.
What is an RCT — and why the "sham control" matters
An RCT (randomised controlled trial) is the gold standard of clinical efficacy research. Three components make it strong:
- Randomisation: participants are allocated to two groups by chance, so that unknown confounders distribute evenly.
- Control group: one group receives the real treatment, the other a comparison condition.
- Blinding: ideally neither participants nor assessors know who is in which group.
With healing practices, the control condition is the real problem. A sugar pill as placebo is easy — but how do you build a "placebo passe"? Cavalcante et al. used a sham passe: the practitioner outwardly performs the same gestures and hand positions, but without the intended transmission of healing fluids. The point: everything non-specific — the attention, the ritual, the calm atmosphere, the expectation — is equal in both groups. A difference between real and sham passe would therefore indicate a specific effect of the practice itself, beyond the placebo effect.
The Cavalcante RCT (2016) in detail
The study appeared in 2016 in Complementary Therapies in Medicine. Key data:
- Setting: UNESP (Universidade Estadual Paulista), Brazil
- Design: prospective, randomised, sham-controlled parallel-group RCT
- Participants: 97 screened, 50 included in the analysis — intervention group (real passe) n=23, control group (sham passe) n=27
- Intervention: eight weekly passe or sham-passe sessions
- Primary endpoint: anxiety, measured with the established State-Trait Anxiety Inventory (STAI-trait)
The results:
- Anxiety scores fell markedly in both groups over the course of the study (p<0.0001) — the expected non-specific effect.
- The decline was, however, more pronounced in the real-passe group (p=0.02).
- At the end of the study only 17% of the passe group still met the criterion for anxiety — versus 63% of the sham group (p=0.001).
"Anxiety was more markedly reduced in participants receiving the Spiritist passe than in controls, warranting larger trials." — Cavalcante et al., Complementary Therapies in Medicine 2016
The authors themselves classify their work as a small pilot study. That very modesty is exemplary: a significant group difference among 50 participants is a hint, not a proof.
The strongest argument: the double-blind preterm-newborn RCT (2018)
The biggest objection to the Cavalcante study is the expectation effect: adult participants might — consciously or not — have noticed whether they were getting the "real" treatment, and belief alone could have produced the effect. This is exactly where a second, methodologically even more interesting study comes in.
In 2018 the Journal of Complementary and Integrative Medicine published a randomised, double-blind passe RCT in preterm newborns in a neonatal unit (intervention n=13, control n=12, three days of real or sham passe each). The crucial point: a preterm newborn can have no expectation, no belief and no placebo effect in the classical sense. If you find a difference here, it is harder to explain by suggestion.
The findings:
- In the passe group respiratory frequency was significantly lower (p<0.05).
- In the control group there was a stronger tendency for rising cortisol (p=0.05) — the passe thus appeared to dampen the rise of the stress hormone cortisol in saliva.
- Heart rate and length of stay were lower in the passe group, but without statistical significance.
Here too: tiny sample (25 babies), effects partly at the significance threshold. But as a study design it is the most honest one could wish for this question.
A small corpus, not a single case
The Cavalcante RCT does not stand alone. Around it a small corpus of passe studies has grown — mostly from Brazilian university hospitals:
- Cardiovascular inpatients (Lucchetti et al., 2016): an RCT on anxiety, depression, pain, muscle tension, well-being and physiological parameters in hospitalised cardiac patients.
- Preoperative anxiety (2019): a double-blind RCT on passe before surgery, published in the Journal of Religion and Health.
- Preterm newborns (2018): see above — the double-blind cortisol RCT.
A scoping review (2023) gathered these works and reaches the expected conclusion: a young, small, methodologically heterogeneous research field with cautiously positive but not robust signals.
How this should be assessed
The sober reading: the passe RCTs suggest that the ritual might have a measurable effect on stress and anxiety parameters beyond the pure placebo effect. This is not proven. The samples are small, blinding is difficult for a practice involving physical proximity, and independent replications outside the spiritist milieu are largely missing. This fits the overall picture of research on "energy healing" and touch-based methods (Reiki, therapeutic touch), which in larger reviews have so far failed to show a robust specific effect.
Keeping the levels apart matters — the same distinction that marks the SPECT study on psychography: a measurable physiological change (lower respiratory frequency, a dampened cortisol rise) says nothing about why it occurs. "Healing fluids" are one interpretation; relaxation-inducing attention in a calm, ritualised setting is another, more parsimonious one. The RCT design can subtract the placebo effect, but it cannot answer the metaphysical question.
Conclusion
The Cavalcante RCT (2016) is the methodologically cleanest single study on the Spiritist passe and a good example that even spiritual healing practices can — and should — be examined under controlled conditions. Its cautious result (anxiety falls more under real than under sham passe), flanked by the double-blind preterm-newborn RCT, is exactly what it is: a serious signal that deserves larger and independent studies — not a proof of efficacy. The most honest sentence comes from the researchers themselves: "…warranting larger trials."
Sources
- Cavalcante RS, Banin VB, de Moura Ribeiro Paula NA, Daher SR, Habermann MC, Habermann F, Bravin AM, da Silva CEC, Modelli de Andrade LG. Effect of the Spiritist "passe" energy therapy in reducing anxiety in volunteers: A randomized controlled trial. Complementary Therapies in Medicine. 2016;27:18–24. doi:10.1016/j.ctim.2016.05.002
- Effects of Spiritist "passe" (Spiritual healing) on stress hormone, pain, physiological parameters and length of stay in preterm newborns: A randomized, double-blind controlled trial. Journal of Complementary and Integrative Medicine. 2018;15(4).
- Lucchetti G et al. Effectiveness of Spiritist "passe" for anxiety, depression, pain, muscle tension, well-being and physiological parameters in cardiovascular inpatients: A randomized controlled trial. Complementary Therapies in Medicine. 2016.
- Effect of Spiritist "Passe" on Preoperative Anxiety of Surgical Patients: A Randomized Controlled Trial, Double-Blind. Journal of Religion and Health. 2019.
- Context: Brazil's spiritist psychiatry; Mediumship in Brazil.