According to many epidemiological studies early prevention of mental health problems is essential in childhood. The objectives are:

– to determine whether a digital-assisted intervention using whole-population screening that targets the most symptomatic 4-year-old children is effective at 12 months after the start of treatment;

– to describe the Finnish Strongest Families intervention model in primary health care.

The target population was children with high level of DBD symptoms screened from the population of 4-year olds attending annual child health clinic check-ups. The RCT study was conducted in southwest-Finland between 2011 and 2013. In the control group, participants (n = 232) were given access to a parent training website and a telephone call from a coach. Participants (n = 232) in the intervention group received internet and telephone delivered the Finnish Strongest Families program.

During the 12-months follow-up results of the intervention showed the behavioural problems of the four-year-old children reduced significantly in the families who participated in the 11-week program compared to the control group. So far, this evidence-based intervention has been implemented in 13 municipalities in Finland and the nationwide implementing process is in progress.

Training parents online and over the telephone significantly decreases preschool children's disruptive behavior. Therefore, it is important to provide low threshold, digitally delivered, family oriented promotion, prevention and early intervention programs in the primary care. More studies are needed to evaluate the long-term effects and cost-effectiveness of digital interventions in preventive mental health care.

The authors have not supplied their declaration of competing interest.