title: The Perseverative Thinking Questionnaire in Patients with Persecutory Delusions.
abstract: BACKGROUND
  Ruminative negative thinking has typically been considered as a factor maintaining common emotional disorders and has recently been shown to maintain persecutory delusions in psychosis. The Perseverative Thinking Questionnaire (PTQ) (Ehring et al., 2011) is a transdiagnostic measure of ruminative negative thinking that shows promise as a "content-free" measure of ruminative negative thinking.
  
  
  OBJECTIVE
  The PTQ has not previously been studied in a psychosis patient group. In this study we report for the first time on the psychometric properties of Ehring et al.'s PTQ in such a group.
  
  
  METHODS
  The PTQ was completed by 142 patients with current persecutory delusions and 273 non-clinical participants. Participants also completed measures of worry and paranoia. A confirmatory factor analysis was performed on the clinical group's PTQ responses to assess the factor structure of the measure. Differences between groups were used to assess criterion reliability.
  
  
  RESULTS
  A three lower-order factor structure of the PTQ (core characteristics of ruminative negative thinking, perceived unproductiveness, and capturing mental capacity) was replicated in the clinical sample. Patients with persecutory delusions were shown to experience significantly higher levels of ruminative negative thinking on the PTQ than the general population sample. The PTQ demonstrated high internal reliability.
  
  
  CONCLUSIONS
  This study did not include test-retest data, and did not compare the PTQ against a measure of depressive rumination but, nevertheless, lends support for the validity of the PTQ as a measure of negative ruminative thinking in patients with psychosis.
authors: University of Oxford,UK.
authors: Emma
authors: E
authors: Černis
authors: Manchester University,UK.
authors: Graham
authors: G
authors: Dunn
authors: University of Oxford,and Sussex Partnership,NHS Foundation Trust,Hove,UK.
authors: Helen
authors: H
authors: Startup
authors: University of Southampton,UK.
authors: David
authors: D
authors: Kingdon
authors: University of Southampton,UK.
authors: Gail
authors: G
authors: Wingham
authors: University of Oxford,UK.
authors: Nicole
authors: N
authors: Evans
authors: University of Oxford,UK.
authors: Rachel
authors: R
authors: Lister
authors: University of Oxford,and Sussex Partnership,NHS Foundation Trust,Hove,UK.
authors: Katherine
authors: K
authors: Pugh
authors: University of Southampton,UK.
authors: Jacinta
authors: J
authors: Cordwell
authors: University of Southampton,UK.
authors: Helen
authors: H
authors: Mander
authors: University of Oxford,UK.
authors: Daniel
authors: D
authors: Freeman
mesh_terms: D000328:Adult; D000067290:Behavior Rating Scale / Q000592:standards; D003702:Delusions / Q000145:classification* / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010259:Paranoid Disorders / Q000523:psychology; D000067657:Pessimism / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D011581:Psychological Tests / Q000592:standards; D011618:Psychotic Disorders / Q000523:psychology; D015203:Reproducibility of Results; D012563:Schizophrenia, Paranoid / Q000523:psychology; D011795:Surveys and Questionnaires
keywords: Perseverative Thinking Questionnaire; Rumination; paranoia; persecutory delusions; psychosis; schizophrenia