. 2021 May 18;20(2):200–221. doi: 10.1002/wps.20869

Table 4.

Level of evidence for population‐level exposures and available universal interventions to prevent (reduce the incidence) of psychotic, bipolar and common (depression/anxiety) mental disorders in young people

	Psychotic disorders	Bipolar disorder	Depression/Anxiety disorders
Population‐level exposures (association with the disorder)	Surrogate markers: psychotic experiences (risk of psychosis 0.5‐1 per year) ²⁹⁰ * Neurodevelopmental biomarkers** (data not available)164, 165, 167*	Surrogate markers: K6/10 (data not available) ¹⁶³ *	Surrogate markers: K6/10 (data not available) ¹⁶³ *
Population‐level exposures (association with the disorder)	Social determinants of mental disorders (data not available) ¹⁷³ **** Demographic (community diversity, population density, longevity, survival) Economic (economic recessions, economic inequalities, macroeconomic policy) Neighbourhood (infrastructure, neighbourhood deprivation, built environment settings) Environmental events (natural/industrial disasters, war or conflict, climate change, forced migration) Social/cultural (community social capital, social stability, culture)
Type of intervention (efficacy)	Screening for psychotic experiences (data not available) ¹⁶¹ * Perinatal phosphatidylcholine (modulated biomarkers of neonatal brain development ¹⁶⁴ ; fewer attention problems and less social withdrawal ¹⁶⁵ ); perinatal folate acid (improved executive functioning) ¹⁶⁷ ; vitamin D, polyunsaturated fatty acids (inconclusive evidence) ¹⁶⁶ *	Screening for bipolar experiences (data not available) ¹⁶³ * Psychoeducation for young people (improved affective symptoms but no evidence of effect on incidence of bipolar disorder) ¹⁵⁵ ***	Screening for depressive/anxiety experiences (data not available) ¹⁶³ * Psychological/psychoeducation (improved anxiety symptoms ¹¹⁵ *, but not as school‐based interventions ¹⁵⁶ * and not in humanitariansettings ¹²⁰ *; no evidence on preventing depression/anxiety disorders ¹¹⁵ ) Public health strategies on school climate (improved depressive symptoms)^171 Physical exercise (reduced incidence of anxiety disorders) ¹⁷⁴ ***
Type of intervention (efficacy)	Reduction of gender‐based violence, child maltreatment, racial discrimination and xenophobia; basic income grants and improved employment; safe neighbourhoods; reductions in violence; early response to environmental events; action on protecting vulnerable ecosystems; improved education (data not available) ¹⁷³ ** Behavioural counselling to prevent illicit substance use in adolescents and young adults (no evidence of efficacy) ¹⁵⁴ *

* single study, ** systematic review, *** meta‐analysis, **** umbrella review. K6/10 – Kessler Distress Scale 6‐ or 10‐item