Evidence map›Paper›PMID 41184421›Full record

ArticleNpj mental health research2025

Unexpected events and prosocial behavior: the Batman effect.

Francesco Pagnini, Francesca Grosso, Cesare Cavalera, Valentina Poletti, Giacomo Andrea Minazzi, Anna Missoni, Laura Bogani, Mauro Bertolotti

Erratum issued Registry-linked trialAbstract read
In one paragraph

Article in Npj mental health research, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. It is linked to trial NCT06481748 (The Batman Project), which is not on this map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

NCT06481748 unknown statusnot on this map

The Batman Project: Can Unpredictability Foster Prosocial Behaviour Through Increased Awareness?

TypeobservationalSponsorCatholic University of the Sacred HeartRan2024 to 2024Enrolled68ConditionsSocial BehaviorArmsBatman
3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Altruism and its relationship to resilience during disaster.Jamba (Potchefstroom, South Africa) · 2026
    Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

8 authors.

Francesco PagniniDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy. francesco.pagnini@unicatt.it.
Francesca GrossoDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Cesare CavaleraDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Valentina PolettiDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Giacomo Andrea MinazziDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Anna MissoniDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Laura BoganiDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.
Mauro BertolottiDepartment of Psychology, Università Cattolica del Sacro Cuore, Milan, Italy.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Prosocial behavior, the act of helping others, is essential to social life, yet spontaneous environmental triggers for such behavior remain underexplored. This study tested whether an unexpected event, such as the presence of a person dressed as Batman, could increase prosocial behavior by disrupting routine and enhancing attention to the present moment. We conducted a quasi-experimental field study on the Milan metro, observing 138 rides. In the control condition, a female experimenter, appearing pregnant, boarded the train with an observer. In the experimental condition, an additional experimenter dressed as Batman entered from another door. Passengers were significantly more likely to offer their seat when Batman was present (67.21% vs. 37.66%, OR = 3.393, p < 0.001). Notably, 44% of those who offered their seat in the experimental condition reported not seeing Batman. These findings suggest that unexpected events can promote prosociality, even without conscious awareness, with implications for encouraging kindness in public settings. Trial registration: ClinicalTrials.gov n° NCT06481748; registered on July 1, 2024.

Identifiers

PMID41184421
PMCPMC12583732

What OpenQuestion holds

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LicenceCC BY-NC-ND
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Registered trials

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.