The Predictability, Opportunity, and Safety Dimensions of Environmental Variability (POS-DEV) Retrospective Scale: A New Tool to Retrospectively Assess Positive Early Life Experiences.

Both positive and adverse developmental experiences have significant impacts across the lifespan. Psychometric measurement of adversity serves multiple conceptual frameworks for parsing experiences; however, existing measurements of positive experiences largely serve count-based frameworks. We present the POS-DEV scale, a retrospective measure of positive experiences with caregivers, close friends, and adult role models across experience dimensions of psychosocial predictability, opportunity, and safety. Exploratory factor analyses (Study 1, n = 406; Study 2, n = 316) reduced items while a confirmatory factor analysis (Study 3, n = 289) confirmed a final factor structure for POS-DEV across childhood and adolescent windows with excellent psychometric properties and construct validity. Six-month test-retest reliability (Study 4, n = 203) was excellent for total scores. Positive experiences explained variation in adult mental health above and beyond adversity effects (Study 5, n = 1,021), highlighting the POS-DEV scale's utility for capturing important but under-measured promotional aspects of the early psychosocial environment.