Method effects associated with negatively and positively worded items on the 12-item General Health Questionnaire (GHQ-12): results from a cross-sectional survey with a representative sample of Catalonian workers

摘要

Recent studies into the factorial structure of the 12-item version of the General Health Questionnaire (GHQ-12) have shown that it was best represented by a single substantive factor when method effects associated with negatively worded (NW) items are considered. The purpose of the present study was to examine the presence of method effects, and their relationships with demographic covariates, associated with positively worded (PW) and/or NW items.