The measurement invariance of schizotypy in Europe

Eur Psychiatry. 2015 Oct;30(7):837-44. doi: 10.1016/j.eurpsy.2015.07.005. Epub 2015 Sep 25.


The short version of the Oxford-Liverpool Inventory of Feelings and Experiences (sO-LIFE) is a widely used measure assessing schizotypy. There is limited information, however, on how sO-LIFE scores compare across different countries. The main goal of the present study is to test the measurement invariance of the sO-LIFE scores in a large sample of non-clinical adolescents and young adults from four European countries (UK, Switzerland, Italy, and Spain). The scores were obtained from validated versions of the sO-LIFE in their respective languages. The sample comprised 4190 participants (M=20.87 years; SD=3.71 years). The study of the internal structure, using confirmatory factor analysis, revealed that both three (i.e., positive schizotypy, cognitive disorganisation, and introvertive anhedonia) and four-factor (i.e., positive schizotypy, cognitive disorganisation, introvertive anhedonia, and impulsive nonconformity) models fitted the data moderately well. Multi-group confirmatory factor analysis showed that the three-factor model had partial strong measurement invariance across countries. Eight items were non-invariant across samples. Significant statistical differences in the mean scores of the s-OLIFE were found by country. Reliability scores, estimated with Ordinal alpha ranged from 0.75 to 0.87. Using the Item Response Theory framework, the sO-LIFE provides more accuracy information at the medium and high end of the latent trait. The current results show further evidence in support of the psychometric proprieties of the sO-LIFE, provide new information about the cross-cultural equivalence of schizotypy and support the use of this measure to screen for psychotic-like features and liability to psychosis in general population samples from different European countries.

Keywords: Cross-cultural; Equivalence; Invariance; Schizotypal; Schizotypy; sO-LIFE.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Adult
  • Europe / epidemiology
  • Factor Analysis, Statistical
  • Female
  • Humans
  • Italy / epidemiology
  • Male
  • Personality Inventory
  • Phenotype
  • Psychometrics / methods
  • Psychotic Disorders / psychology
  • Reproducibility of Results
  • Schizotypal Personality Disorder / classification*
  • Schizotypal Personality Disorder / diagnosis*
  • Schizotypal Personality Disorder / psychology
  • Spain / epidemiology
  • Surveys and Questionnaires / standards*
  • Switzerland / epidemiology
  • Young Adult