The Relative Age Effect and Trajectories of Alcohol Use Across Adolescence

• In Event: Poster Session 13
  In Poster Session: PS 13 Topic - Developmental Psychopathology

Abstract

Background
The relative age effect (RAE; Barnsley et al., 1985) is a phenomenon in which children who are relatively old for a given cohort (e.g., their kindergarten class) experience considerable advantages relative to their peers, typically in academic and athletic domains (Musch & Grondin, 2001; Verachtert et al, 2010). While most research on RAEs has focused on academic and athletic performance, a smaller body of work has examined the impact of relative age on social-emotional outcomes. RAEs have been found in relation to depression, low self-esteem, and low levels of assertiveness, with younger age conferring disadvantages (Dhuey & Lipscomb, 2008; Patalay et al., 2015; Thompson et al., 2004). Interestingly, these same social-emotional issues have been robustly implicated in teen alcohol use (e.g., Allen, et al., 2011; Handren et al., 2016; Wu et al., 2006). However, to our knowledge, no research has explored whether relative age could be associated with teen alcohol use patterns. The present study examined the possibility that relative age may be associated with differing trajectories of alcohol use across the teenage years.

Methods
Participants: 182 adolescents (85 males, 97 females), followed longitudinally from eighth grade (Wave 1) to 12th grade (Wave 5). 58% identified as Caucasian, 29% as African American, 8% as mixed race/ethnicity, and 5% as other race/ethnicity.

Measures: At each wave, participants reported how many times they had consumed alcohol in the past 30 days. Control variables were collected at Wave 1, and included gender, family income, close friend alcohol use, and parent alcohol/drug attitudes.

Analyses: Analyses were conducted in R using “OpenMX” (Boker et al., 2011), a SEM package. We used latent growth curve modeling, fit by FIML estimation, to examine initial level and change in adolescents’ alcohol use from eighth to 12th grade, with relative age as a moderator in the model.

Results
The model fit the data well. Fit indices were as follows: χ2(14) = 17.05, p =0.25, RMSEA=0.03 (95% CI [0, 0.09]); TLI=0.98; CFI=0.99. Income significantly predicted slope, β = 0.031, SE = 0.012, 95% CI [0.01, 0.05]. Relative age predicted slope but not intercept: β = -0.072, SE = 0.036, 95% CI [-0.14, -0.0003]. Post-hoc, an independent samples t-test was run to examine whether 12th graders who consumed 1-2 drinks in the past 30 days differed in relative age from those who reported consuming 3-4 drinks. Lighter drinkers were on average 14.3 days older than the rest of their peers (SD=230), while heavier drinkers were on average 112.8 days younger than the rest of their peers (SD=237.3), t(69)=2.11, p=0.039.

Conclusions
In line with previous research indicating relative youth to be a potential social-emotional risk factor, this study identified relatively young age as a risk factor for steeper increases in alcohol use across adolescence and heavier drinking in the 12th grade. Relative age effects appear to be a promising, but largely unexplored, new factor to consider in the alcohol use literature. Future research should seek to elucidate why relatively young adolescents drink more heavily across time than their older counterparts.

Authors

• Alida Davis, University of Virginia - Charlottesville
  Presenting Author

• Joseph P Allen, University of Virginia - Charlottesville
  Non-Presenting Author