A meta-analysis on age differences in helping behaviors from infancy to toddlerhood

The early development of prosocial behavior has been of considerable research interest since the early 1970s, yet the developmental trajectory of these behaviors is still not clear. While some researchers proposed that prosocial behaviors will increase in frequency and complexity from infancy to childhood (e.g., Eisenberg & Fabes, 1998; Eisenberg, Fabes, & Spinrad, 2006), others suggest that those behaviors will decrease as children become more self-regulated and selective (e.g., Hay, 1994; Hay, Castle, Davies, Demetriou, & Stimson, 1999). For a better understanding of this development, the current meta-analysis study focuses on helping behavior, an action aimed at alleviating instrumental need, which is one of the earliest emerging forms of prosocial behavior (Brownell, Svetlova, & Nichols, 2009). Only studies that used experimental or observational measures of helping were included. A literature search using primarily PsycINFO identified 32 eligible articles with at least two age groups (infant, toddler, preschool and children). No studies were found for adolescents. We used Cohen’s D and the Q-test for heterogeneity test. All statistical analyses were conducted using meta-analysis macros (MeanES, Wilson D, 2001) in the statistical software SPSS V.22.0. For experimental settings, results yielded a significant mean effect size for age differences comparing infants to toddlers (0.73, p < .01), within toddlerhood (0.44, p < .01), and comparing toddlers to preschoolers (0.33, p < .01). In addition, the heterogeneity test for each group comparison was not significant (ps > 0.30), indicating that the results from different experimental settings are sufficiently similar to warrant their combination into an overall result (Kulinskaya, Dollinger, & Bjørkestøl, 2011). For observational settings, the effect size was not significant from preschool to children (0.12, p = 0.35) and within children (0.16, p = 0.25), suggesting there is no significant increase in helping from preschool to childhood. There was insufficient number of observational studies focusing on infants and toddlers to make an analysis. The findings indicate an increase in the early development of helping behavior, however, the pace of this increase seems slow down during the preschool years. Shortcomings related to studies about helping behaviors are discussed.