Validation of the short Oxford-Liverpool Inventory of Feelings and Experiences (SO-LIFE) on an Iranian sample

The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a 104-item instrument that has been designed based on a factor analysis of 15 existing scales for the measurement of schizotypy. The present study was an attempt to validate the short form of the O-LIFE (SO-LIFE). This study was a correlational research wherein a sample of four hundred and sixty-eight participants was selected among Tabriz Payame Noor university students via a stratified random sampling in 2022. The data was analyzed using factor analysis. Factor analysis using principal component analysis (PCA) with Promax rotation extracted four factors including cognitive disorganization, impulsive nonconformity, unusual perceptual experiences, and introversive anhedonia. Concurrent validity coefficient of the scale was equal to 0.85 and the correlation coefficient between the total scale and the subscales ranged from 0.46 to .75. Differential validity was tested by comparing SO-LIFE scores between schizophrenic patients, their first degree relatives and normal people which was acceptable. In the same way, test-retest reliability and internal consistency reliability of the scale were equal to 0.83 and 0.75 respectively. The findings of this study revealed some information about the psychometric properties of the O-LIFE short form in an Iranian sample. It was also found that this questionnaire, as a valid instrument, had applications in research on schizophrenia spectrum disorders in Iran.
The employment of this questionnaire can help develop a comprehensive body of research wherein accurate measurement of schizotypy would be of particular importance.