Objectives:
Cognitive and affective experiences considered typical of psychotic disorders may also occur in the general population,though in aless severe form. The ability to differentiate them from prodromal states, preceding the onset of full-blown psychosis, is an important element of prevention and early detection of high risk of asudden deterioration of mental state. In response to the current lack of questionnaire tools enabling assessment of psychotic-like experiences (PLEs), an attempt was made to adapt the PQ–B questionnaire for use in the Polish population.

Methods:
In the pilot study, a sample of 652 persons (66% women), aged 18–78 years, approximately 10% of whom were psychiatric patients, completed the Polish version of the PQ–B, and the O–LIFE, HCL–33, SWLS and TCT–DP measures.

Results:
Results yielded a one-factor structure, satisfactory reliability (α > 0.85) and construct validity of the 21-item self-report questionnaire assessing the incidence of PLEs in the past month and severity of accompanying distress. Furthermore, there were significant correlations between PQ–B scores and symptoms of schizotypy (especially unusual perceptual experiences and cognitive disorganization), emotional lability (p < 0.05) and depressed mood (p > 0.001) typical of hypomania, as well as unconventional thinking (p > 0.05).

Conclusions:
The PQ–B(PL) can be a useful tool in both Polish clinical practice and scientific research, filling the existing gap among screening tests for traits on the border of health and psychopathology.