TWO COMPLEMENTARY FINNISH RESEARCH STUDIES

This book celebrates two sets of ongoing longitudinal research studies conducted in Finland. In the 16 chapters that follow, the principal investigators of the Finnish longitudinal studies introduce their research designs, and 25 of their collaborators selectively review recent research results from these studies. Reports from the Jyväskylä Longitudinal Study of Personality and Social Development (JYLS), now in its 38th year and with accumulated observations on its participants from mid-childhood to mid-adulthood, make up much of the book. The JYLS reports are presented in the context of emerging theory and prospective data relating childhood assessments of socioemotional behavior to educational, occupational, and social success, and to physical and psychological health at later follow-up. The rich multi-occasion, multilevel longitudinal data of the JYLS are related to social, educational, and occupational outcomes, and to self-esteem, health, and well-being. Research publications from the Jyväskylä Longitudinal Study have importantly contributed to our conceptual understanding of the role of emotional and behavioral regulation and self-control in life-span development, and the reports contained in this volume update empirical results from the study and extend its conceptual contributions.

Reports from two longitudinal studies of families of young Finnish twins, now in their 15th year of data collection, make up the balance of this volume. Each of the two FinnTwin studies sequentially enrolled twins over 60-month periods of baseline data collection to achieve age-matching across five consecutive twin birth cohorts; each was designed to address environmental as well as genetic influences on children's development.