When risk lies in inaction: Age differences in protective intervention during sequential health-risk decisions

Adolescent risk research often reports elevated risk-taking in active, reward-salient contexts, but age differences vary across tasks and domains. We examined age differences in protective sequential decisions in which delaying action can carry potential cost. A total of 277 consenting participants (224 adolescents and 53 adults; age recorded categorically), recruited through UK school, parent, and teacher networks, evaluated hypothetical health scenarios unfolding across up to five stages. At each reached stage, they chose whether to continue monitoring or seek help; the first help-seeking response defined the intervention threshold. The primary analysis used a standardized presentation of symptoms, experimental urgency scores, and a visual bar. Adolescents intervened in 98.9% of analyzable scenarios, compared with 94.7% for adults. Among scenarios with an observed intervention, adolescents acted at lower experimental urgency scores (M = 14.37 vs. 18.22) and earlier steps (M = 2.66 vs. 3.32). A discrete-time logistic model estimated with participant-clustered generalized estimating equations (GEE) showed higher adolescent intervention odds at the analytical reference urgency of 12 (OR = 8.45, 95% CI [4.53, 15.76]). Model-predicted probabilities at a reached stage with this urgency were 74.0% and 26.6%, respectively. Lower adolescent thresholds in this protective task highlight the value of testing developmental age patterns across decision contexts while specifying what the available actions represent.