Validation of the Prospective Memory Concerns Questionnaire Informant Scale (PMCQi): How personality and self/proxy...

Due to potential biases, the validity of informant reports of prospective memory (PM) is unclear. This study reports on the adaptation and validation of the Prospective Memory Concerns Questionnaire-informant version (PMCQi). We aimed to investigate whether PMCQi scores corresponded to self-report and performance on an event-based PM task. Additionally, we explored whether informants' Big Five personality traits or relationship characteristics between ratee and informant influenced scores. Participants comprised of 305 adults who completed self-report versions of the PMCQ, Prospective and Retrospective Memory Questionnaire, and Big Five Inventory and completed an event-based PM task. Informant versions of the PMCQ and Prospective and Retrospective Memory Questionnaire, self-reported Big Five Inventory, and task success judgements were completed by informants who knew the participants well: 246 participants had one informant, and 59 had two. The PMCQi scores had very good reliability, the same higher order three-factor structure as the PMCQ, and agreement with self-report PMCQ. Both self-report and informant PMCQ scores predicted event-based PM performance. Neither relationship status nor personality moderated these relationships. Contrary to expectations, the type, frequency, and duration of self-informant relationships did not influence PMCQi scores. As expected, neuroticism predicted higher PMCQi scores. Agreeableness on the other hand predicted fewer PMCQi concerns. The current findings demonstrate the validity of the PMCQi and its usefulness alongside self-report PMCQ and performance measures. Our findings suggest that the nature of self-informant relationship is less important than informant agreeableness and neuroticism when assessing PM concerns. As such, clinicians and researchers should be mindful of personality factors when assessing PM concerns. (PsycInfo Database Record (c) 2026 APA, all rights reserved).