Validation of Peters et al delusions inventory (short form) in Chinese population

Abstract

BACKGROUND: Psychotic symptoms have been suggested as a continuum that normal population may also experience hallucination and delusional ideas. METHODS: Peters et al. Delusions Inventory (PDI-21) is a well validated scale designed to measure delusional ideations in general population. It is a multidimensional scale with 21 individual items and three rating dimensions: distress, preoccupation and conviction on each item, respectively. It was translated into Chinese and validated in 108 Hong Kong university students. Backward translation was adopted to minimize any deviation on sentences meaning from original scale. Internal consistency was found to be satisfactory that the Cronbach alpha of reliability was 0.66. RESULTS: The mean of distress, preoccupation and conviction was 6.63, 6.34 and 8.92 in the scoring range of 0 to 105, respectively. The correlations of these three rating scales were significant ( p < 0.01). Among the 21 items, some were rated more frequently than others. For examples, 74.1% of the students felt that people are not what they seem to be, 46.8% felt that people seem to drop hints about them and 37.6% believed in the power of witchcraft. CONCLUSION: The results show that Chinese university students do experience some psychotic-like symptoms but with mild distressing, preoccupation and conviction levels. Further studies are required to improve the sample base with a more diverged normal population as well as to compare the scores with psychotic patients.