Internal structure of the prospective and retrospective memory questionnaire - PRMQ - in a sample of 297,242 participants.

The prospective and retrospective memory questionnaire (PRMQ) is one of the most widely used questionnaires to assess subjective memory through self-reporting of common memory failures. There have been mixed results in the literature regarding its internal structure. The early studies favoured a tripartite structure with one factor representing a general memory and two group factors representing retrospective (RM) and prospective memory (PM) components. Other findings favoured different structures, such as with only a single factor or only two factors (PM and RM). The objective of the present study was to verify the internal structure of the PRMQ in a very large sample and with precise modelling. We analysed data from 297,242 adult participants, with ages ranging from 18 to 79 years, and used exploratory and confirmatory factor analysis to examine the internal structure of PRMQ. The results showed that the model that best describes the data was one with a single factor. The tripartite model failed to converge and our results indicate that the PRMQ is a unidimensional instrument. This is relevant especially for researchers interested in using the PRMQ in future studies and professionals using the questionnaire in clinical settings.