Table 3 6SQuID step 2: causal and contextual factors that have scope for change and step 4: how to deliver the change mechanism

Step 2: clarify which causal or contextual factors are malleable and have greatest scope for change

Positive peer influences and family/social networks can offer a protective effect, and this knowledge can be incorporated into and encouraged within interventions, both at an early stage and as adolescents mature

School schedules may benefit from later start times, if feasible. Ensuring that adolescents themselves, parents, and teachers understand adolescent sleep issues is important; limited late evening screen use and consistent sleep patterns can be promoted

Information may need to be matched to stage of readiness to receive and/or stage of maturity rather than simply age related. Earlier maturation of girls is a factor.

Teaching staff and school nurses are well placed to monitor early need for sexual/relationship education, in liaison with parents

Physical activity (PA) programmes may need to be altered to take account of gender and body image issues, especially during periods of rapid physical change in adolescence.

PA trainers/teachers are central to implementing changes, such as increasing privacy or altering venues

Information regarding healthy eating needs to be embedded in early education to ensure healthy patterns and understanding predate puberty; school policies regarding meal/snack consumption may be less easy to alter or implement, but ensuring adolescents, teachers, and parents are aware of the nutritional needs of adolescents, and healthy BMI perimeters, may assist. Stress coping strategies can be implemented to help reduce unhealthy eating tendencies linked to anxiety

Step 4: identify how to deliver the change mechanism

Interventions to promote healthy attitudes to substance use may be most effective when they involve peer and social groups throughout adolescence, but certainly starting at an early stage and for those who mature early

Educating adolescents, parents, and teachers about the changing needs of adolescents regarding sleep and sleep patterns may be an effective way of promoting understanding, and good ‘sleep health’

Delivering sex and relationship education according to maturity, stage of readiness to receive, and with gender adaptations may help to target information in the best way and at the optimum time.

This may require parental, adolescent, and professional judgement and input

Interventions to promote physical activity in girls need to adapt to take account of changing bodies and self-consciousness and promote the benefits of being and looking healthy. This may be better targeted towards younger adolescents before reduced activity patterns are formed

Encouraging healthy eating behaviour and knowledge can be introduced pre-puberty and emphasised as bodily changes occur during puberty. Links with activity and sleep also need to be emphasised. Stress-coping strategies could be incorporated into life skills sessions

Delivery potential