Validation of the verbal and social interaction questionnaire: nurses' focus in the nurse-patient relationship in forensic nursing care.

There is a need to develop a questionnaire that measures nurses' verbal and social interactions (VSI) with their patients from the nurses' perspective as well as from the patients' perspective in the psychiatric and especially in the forensic psychiatric field. The major aim of the present study was to determine the construct validity and the internal consistency reliability of the VSI questionnaire. The study had a methodological and developmental design and was carried out in four steps: construction of the items, face validity, data collection and data analysis. The number of items was reduced from 50 to 21. The factor analysis of the final 21 items resulted in three quite distinct factors, namely, 'inviting the patient to establish a relationship', 'showing interest in the patients' feelings, experiences and behaviour' and 'helping the patients to establish structure and routines in their everyday life'. The results showed satisfactory psychometric properties in terms of content validity, construct validity and the internal consistency reliability of the questionnaire.