Paranoia is considered a key characteristic of schizotypy and schizophrenia, although it also shares phenomenological features with social anxiety (e.g., social fear and discomfort). Our first study examined the relation of paranoia with positive and negative schizotypy and with social anxiety. The second study examined the experience of paranoia and social anxiety in daily life using experience sampling methodology (ESM).

Study 2: Participants were 862 university students who completed the Perceptual Aberration, Magical Ideation, Physical Anhedonia, and Social Anhedonia Scales, the Schizotypal Personality Questionnaire, the Paranoia Checklist, the MMPI-2 Persecutory Ideas subscale, and the Social Phobia Scale. Study 1: A subset of 240 participants from study 1 carried palm pilots for 7 days that signaled them randomly 8 times daily to complete brief questionnaires inquiring about their cognitions, affect, activities, and social functioning at the time of the signal.

A series of confirmatory factor analyses indicated that the best fitting model was a four-factor model with positive and negative schizotypy, paranoia, and social anxiety. As hypothesized, the paranoia factor was most strongly associated with positive schizotypy. While some measures of paranoia correlated with negative schizotypy, measures of core features of paranoid ideation were only minimally associated with negative schizotypy. Social anxiety comprised a separate factor outside of schizotypy, but was moderately associated with positive schizotypy and paranoia.

ESM findings indicated that paranoia and social anxiety are differentially experienced in daily life. The results are consistent with a multidimensional model of schizotypy/schizophrenia.