Background: The Frankfurt Complaint Questionnaire (FCQ) is a questionnaire designed to evaluate the subjective symptoms of schizophrenics. In schizophrenic samples, several validation studies of the FCQ using principal components analyses (PCA) have shown a one-factor solution.
Aim: The aim of the present study was firstly to examine the factor structure and the psychometric properties of the FCQ in a sample of 399 students and secondly to explore the reliability of the FCQ-24, a 24-item subscale extracted from the FCQ.
Method: PCA was done using several guidelines to select the number of factors.
Results: PCA yielded one factor, and the values of the Cronbach alpha were 0.95 and 0.87 for FCQ and FCQ-24, respectively.
Conclusions: These results firstly suggested an unidimensionality underlying FCQ items in nonpsychiatric samples and secondly confirmed the satisfactory reliability and validity of the FCQ and its subscale. Psychometric properties of the rating scales must be confirmed in other nonpsychiatric samples.
Clinical relevance: As subjective symptoms allow to detect subjects prone to schizophrenia, it is important to use well-validated rating scales.
(c) 2007 S. Karger AG, Basel.