Conceptual comparison of constructs as first step in data harmonization: Parental sensitivity, child temperament, and social support as illustrations

This article presents a strategy for the initial step of data harmonization in Individual Participant Data syntheses, i.e., making decisions as to which measures operationalize the constructs of interest - and which do not. This step is vital in the process of data harmonization, because a study can only be as good as its measures. If the construct validity of the measures is in question, study results are questionable as well. Our proposed strategy for data harmonization consists of three steps. First, a unitary construct is defined based on the existing literature, preferably on the theoretical framework surrounding the construct. Second, the various instruments used to measure the construct are evaluated as operationalizations of this construct, and retained or excluded based on this evaluation. Third, the scores of the included measures are recoded on the same metric. We illustrate the use of this method with three example constructs focal to the Collaboration on Attachment Transmission Synthesis (CATS) study: parental sensitivity, child temperament, and social support. This process description may aid researchers in their data pooling studies, filling a gap in the literature on the first step of data harmonization. • Data harmonization in studies using combined datasets is of vital importance for the validity of the study results. • We have developed and illustrated a strategy on how to define a unitary construct and evaluate whether instruments are operationalizations of this construct as the initial step in the harmonization process. • This strategy is a transferable and reproducible method to apply to the data harmonization process

Neonatal Handling Affects Durably Bonding and Social Development

The neonatal period in humans and in most mammals is characterized by intense mother-young interactions favoring pair bonding and the adaptation of neonates to their new environment. However, in many post-delivery procedures, human babies commonly experience combined maternal separation and intense handling for about one hour post-birth. Currently, the effects of such disturbances on later attachment and on the development of newborns are still debated: clearly, further investigations are required. As animals present good models for controlled experimentation, we chose domestic horses to investigate this issue. Horses, like humans, are characterized by single births, long lactating periods and selective mother-infant bonds. Routine postnatal procedures for foals, as for human babies, also involve intense handling and maternal separation. In the present study, we monitored the behavior of foals from early stages of development to “adolescence”, in a normal ecological context (social groups with adults and peers). Experimental foals, separated from their mothers and handled for only 1 hour post-birth, were compared to control foals, left undisturbed after birth. Our results revealed short- and long-term effects of this unique neonatal experience on attachment and subsequent social competences. Thus, experimental foals presented patterns of insecure attachment to their mothers (strong dependence on their mothers, little play) and impaired social competences (social withdrawal, aggressiveness) at all ages. We discuss these results in terms of mother-young interactions, timing of interactions and relationships between bonding and subsequent social competences. Our results indicate that this ungulate species could become an interesting animal model. To our knowledge, this is the first clear demonstration that intervention just after birth affects bonding and subsequent social competences (at least until “adolescence”). It opens new research directions for studies on both humans and other animals

Stability of Genetic and Environmental Contributions to Anxiety Symptoms in Older Adulthood

Anxiety symptoms are common in later life and are associated with diverse adverse health outcomes. Little is known about how genetic and environmental influences on anxiety symptoms might vary across older adulthood. The purpose of this study was to explore change and stability of contributions to anxiety symptoms across older adulthood. We examined data from the Swedish Adoption/Twin Study of Aging (SATSA). Between the years 1984 and 2010, 2,021 participants (including 753 complete twin pairs) completed up to seven assessments containing two measures of anxiety symptoms. Longitudinal genetic simplex models were fit to examine the stability and change in genetic and environmental influences. Amplification of genetic factors at ages 75–80 suggests tentative new genetic contributions to anxiety symptoms. These findings suggest that the heritability of anxiety symptoms may increase later in life. Physiological factors associated with aging are discussed as potential factors explaining this increase