Planetary-health literacy and mental wellbeing in Czech adolescents: insights from the HBSC survey 2022.

Girls scored higher than boys on all planetary-health literacy domains.

• Sex differences were observed across all three PHL sub-scales: knowledge, action, and perceived pro-environmental social norms.
• Effect sizes were small, with Cohen d ranging from 0.10 to 0.19.
• Sample was drawn from the nationally representative HBSC 2022 survey (n = 4,195, 50.8% boys, ages 13 and 15 years).

Younger adolescents (13-year-olds) reported more action and stronger pro-environmental social norms than older adolescents (15-year-olds).

• Differences in action and social norms sub-scales by grade were statistically significant (p < 0.001).
• Socioeconomic gradients across family affluence levels were described as small.
• PHL was measured with an 11-item HBSC optional package yielding three sub-scales.

Perceived pro-environmental social norms were positively associated with wellbeing and life satisfaction, and inversely associated with psychological complaints.

• Social norms were positively associated with wellbeing (β = 1.42, 95% CI: 1.12–1.72).
• Social norms were positively associated with life satisfaction (β = 0.10, 95% CI: 0.08–0.13).
• Social norms were inversely associated with psychological complaints (β = -0.27, 95% CI: -0.33 to -0.21).
• These associations were found in fully adjusted models.
• Wellbeing was measured with WHO-5, life satisfaction with Cantril's ladder, and psychological complaints with the HBSC symptom checklist.

PHL knowledge showed weak adverse associations with wellbeing and psychological complaints.

• Unlike social norms, knowledge was associated with worse rather than better mental health outcomes.
• The adverse relations with wellbeing and complaints were described as weak.
• These findings were from fully adjusted regression models.

PHL action sub-scale was associated with wellbeing only, with no significant association with other mental health outcomes reported.

• Action was associated with wellbeing but not reported as significantly associated with life satisfaction or psychological complaints in fully adjusted models.
• This distinguishes the action sub-scale from the social norms sub-scale, which was associated with all three mental health outcomes.

Higher planetary-health literacy was associated with daily fruit and vegetable consumption and inversely associated with intensive e-cigarette use.

• Fruit and vegetable intake and cigarette and e-cigarette use served as behavioural correlates in the analysis.
• Effect sizes for these behavioural associations were described as modest.
• The inverse association was specifically noted for intensive e-cigarette use.