Extensive evidence now supports an association between early pubertal timing and increased risk of antisocial/externalizing behaviour in adolescent girls (Mendle et al, 2007). To date, the mechanisms underlying this association remain unclear. A recent review (Ge & Natsuaki, 2009) outlined four possible hypotheses: (i) a hormonal influence hypothesis, whereby increases in hormone levels at puberty lead to increased risk for psychopathology; (ii) a maturation disparity hypothesis, whereby the gap between physical, social, and psychological maturation in early maturers is thought to exact a toll on individual adjustment; (iii) a contextual amplification hypothesis, whereby experiencing early puberty in a disadvantaged context is argued to increase risk for psychopathology; and (iv) an accentuation hypothesis, whereby risk for early maturers is argued to derive primarily from pre-existing vulnerabilities.

Our on-going analyses of risks for adolescent onset conduct problems in ALSPAC (Project B235) have included early pubertal timing (operationalized as reaching Tanner stage IV by age 12) as a moderator of other potential risks. These preliminary analyses have convinced us that the ALSPAC data-set offers important opportunities to examine the mechanisms underlying associations between early puberty and girls' conduct problems/delinquency in a more general way. As a result, we are requesting agreement to undertake analyses for two papers in which pubertal timing would constitute the main exposure, the first focusing on the adolescent maturity gap (hypothesis (ii) above), and the second on elements of both the contextual amplification and the accentuation hypotheses (hypotheses (iii) and (iv) above).

(A) Paper 1: The adolescent maturity gap

The concept of the adolescent 'maturity gap' (the discrepancy between physical and sexual maturation on the one hand and continued material and legal dependence on caregivers on the other) has been widely canvassed as one explanation for increased rates of problem behaviour in adolescence (see e.g. Moffitt, 1993). We propose to examine pathways from variations in pubertal timing to adolescent problem behaviour (mother-reported Conduct Problems as measured by the Strengths and Difficulties Questionnaire) via a number of "advanced social behaviours", that is, behaviours that are normative in late adolescence and adulthood but less so in early adolescence. We propose to characterize such behaviours using indicators of spare-time activities (as assessed in Teen Focus 1), and early romantic relationships (as assessed in Teen Focus 2). Early pubertal timing will constitute the predictor for adolescent problem behaviours in these analyses, and we hypothesize any associations found will be partially mediated by engagement in these advanced social behaviours.

(B) Paper 2: Contextual amplification and accentuation effects

In the second paper we propose to examine: (i) the extent to which early maturers showed elevated rates of conduct problems prior to the onset of puberty (using the repeated Strengths and Difficulties measures completed by parents from age 4); (ii) the extent to which early maturing girls (a) come from socially disadvantaged family backgrounds, and (b) are differentially 'selected into' disadvantaged social contexts in adolescence, focusing specifically on peer deviance; (iii) whether these contextual factors moderate effects of early puberty on self-reports of delinquency at ages 12 and 15 years; and (iv) whether early pubertal timing is differentially associated with differing developmental trajectories of conduct problems (as typified by our past analyses of conduct problem trajectories [Barker & Maughan, 2009]) either as a main effect or a moderator of other contextual/environmental risks.

References

Barker, E. D., & Maughan, B. (2009). Differentiating Early-Onset Persistent Versus Childhood-Limited Conduct Problem Youth. American Journal of Psychiatry, 166, 900-908.

Ge, X., Natsuaki, M.N., 2009. In search of explanations for early pubertal timing effects on developmental psychopathology. Current Directions in Psychological Science 18, 327-331.

Mendle, J., Turkheimer, E., Emery, R.E., 2007. Detrimental psychological outcomes associated with early pubertal timing in adolescent girls. Developmental Review. 27, 151-171.

Moffitt, T.E. (1993). Adolescence-limited and life-course-persistent antisocial behaviour - a developmental taxonomy. Psychological Review, 100, 674-701