Season of birth and population schizotypy: Results from a large sample of the adult general population.
Although the last years have seen an increasing interest in schizotypy and its pathogenesis, there exist only a handful of studies examining the possible interaction between season of birth (SOB) and schizotypic personality structure. Available research used differing screening instruments, rendering comparisons between studies difficult, and sample sizes in adult populations may have been too small to detect a mild effect. The current study examined the association between SOB and psychometric schizotypy in the so far single-largest sample from the adult general population (N=8114), balanced for men and women, and utilizing a valid and reliable instrument for the assessment of schizotypy. Using the 12 most informative items of the Schizotypal Personality Questionnaire Brief, we obtained evidence of a small, but significant, effect of late winter and early spring births (February/March) on psychometric schizotypy. The effect was not constrained to women, but affected men and women alike. The observed association between SOB and schizotypy appears compatible with seasonal variations of temperature and influenza prevalence, and with recent evidence on seasonal variability in the activity of the human immune system. Our findings lend support to the continuum hypothesis of schizotypy and schizophrenia, for which SOB effects have been previously established.
Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, Vienna, Austria.
Lisa
L
Konrath
Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, Vienna, Austria.
Danièle
D
Beckius
Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, Vienna, Austria. Electronic address: ulrich.tran@univie.ac.at.
Ulrich S
US
Tran
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D036801:Parturition; D010551:Personality; D015995:Prevalence; D011594:Psychometrics; D012559:Schizophrenia / Q000453:epidemiology*; D012569:Schizotypal Personality Disorder / Q000453:epidemiology*; D012621:Seasons; D011795:Surveys and Questionnaires; D013696:Temperature; D055815:Young Adult
Adult general population; SOB; Schizotypy; Season of birth; Seasonal effect; Seasonality; Winter birth