Abstract
Objective
Existing scales that seek to measure alterations in self-experience were developed based on studies conducted in developed countries. Therefore, the aim of this study was to evaluate the psychometric properties of the Ego Dissolution Inventory (EDI) after translating and adapting it for the Brazilian context.
Methods
The measure was translated by two translators fluent in both English and Portuguese, followed by back-translation into English to ensure there was no loss of meaning. The scale was used in an online survey exploring substance use. A total of 528 participants answered the full scale. We calculated the Kaiser-Meyer-Olkin (KMO) measure to evaluate sampling adequacy, then ran exploratory factor analysis (EFAs) to investigate the factor structure of the EDI.
Results
The scale showed acceptable psychometric properties, with excellent internal consistency and sampling adequacy for factor analysis. Kaiser-Guttman’s criteria and Hull’s method indicated a three-factor solution, while parallel analysis suggested a two-factor solution. All items showed salient loadings, with two items exhibiting cross-loading. Positive but weak correlations were found between EDI factors 1 and 2 and nature relatedness.
Conclusions
The validated scale showed solid psychometric properties, with potential differences in factor structure in relation to the English version. Considering validation is an ongoing process, it is recommended that studies be conducted comparing ego dissolution scores across distinct substances and different regions of the country.
Ego dissolution; ego death; psychedelics; hallucinogens; psychometrics