Prevalence and correlates of self-reported psychotic symptoms in the British population.
BACKGROUND
The psychosis phenotype is generally thought of as a categorical entity. However, there is increasing evidence that psychosis exists in the population as a continuum of severity rather than an all-or-none phenomenon.


OBJECTIVE
To investigate the prevalence and correlates of self-reported psychotic symptoms using data from the 2000 British National Survey of Psychiatric Morbidity.


METHODS
A total of 8580 respondents aged 16-74 years were interviewed. Questions covered mental health, physical health, substance use, life events and socio-demographic variables. The Psychosis Screening Questionnaire (PSQ) was used to identify psychotic symptoms.


RESULTS
Of the respondents, 5.5% endorsed one or more items on the PSQ. Factors independently associated with psychotic symptoms were cannabis dependence, alcohol dependence, victimisation, recent stressful life events, lower intellectual ability and neurotic symptoms. Male gender was associated with paranoid thoughts, whereas female gender predicted hallucinatory experiences.


CONCLUSIONS
Self-reported psychotic symptoms are less common in this study than reported elsewhere, because of the measure used. These symptoms have demographic and clinical correlates similar to clinical psychosis.
Johns
Louise C
LC
Department of Psychological Medicine, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK. ljohns@iop.kcl.ac.uk
Cannon
Mary
M
Singleton
Nicola
N
Murray
Robin M
RM
Farrell
Michael
M
Brugha
Traolach
T
Bebbington
Paul
P
Jenkins
Rachel
R
Meltzer
Howard
H
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D011618:Psychotic Disorders / Q000453:epidemiology*; D012111:Residence Characteristics; D012307:Risk Factors; D012423:Rural Health; D012650:Self Disclosure; D017678:Sex Distribution; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D006113:United Kingdom / Q000453:epidemiology; D014504:Urban Health