Diagnostic stability in a Dutch psychosis incidence cohort.
BACKGROUND
No study outside the UK has examined the diagnostic stability of psychotic disorders in a population-based sample.


OBJECTIVE
To determine diagnostic stability in a Dutch population-based psychosis incidence cohort, to examine the frequencies of diagnostic shifts to and from schizophrenic disorders and to report the revised relative risks of schizophrenic disorders for immigrants.


METHODS
A 30-month follow-up study assessed the cohort (n=181) by means of face-to-face diagnostic interviews.


RESULTS
Diagnostic stability of schizophrenic disorders was high (91%), but lower for other psychotic disorders. At follow-up, the initial diagnosis was adjusted to schizophrenic disorder more often than that the reverse occurred. Almost half (49%) of the patients who were not initially diagnosed as having a schizophrenic disorder received this diagnosis at follow-up. The relative risks for most immigrant groups were stable.


CONCLUSIONS
Schizophrenic disorders are underdiagnosed, rather than overdiagnosed, at first presentation.
Veen
Natalie D
ND
Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center, Utrecht, The Netherlands. n.veen@psych.azu.nl
Selten
Jean-Paul
JP
Schols
Diede
D
Laan
Winfried
W
Hoek
Hans W
HW
van der Tweel
Ingeborg
I
Kahn
René S
RS
D015331:Cohort Studies; D004641:Emigration and Immigration; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000453:epidemiology; D012307:Risk Factors; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology