Editorial Perspective: How spreading mental health information can be (un-) helpful - a dynamic systems approach.

Increasing awareness of mental health problems, including that of young people, is generally seen as positive, and many interventions to increase awareness are underway internationally. Yet, a principled evaluation of the benefits and harms of increasing awareness is still lacking. Here, we present a conceptual framework for the evaluation of information interventions that are aimed at increasing public awareness of mental health problems. We borrow concepts from dynamic systems, such as infection spread and related population growth, to ask how benefits, but also harms of information on mental health, may accrue over time. We argue that as information spreads, several cascades of events are set off that involve members of the general public but also clinicians and healthcare services. These cascades entailinvolve positive and negative feedback loops. We discuss not only how increased diagnoses can lead to positive outcomes (e.g. increasing diagnostic rates and appropriate treatments in those who would otherwise have remained undiagnosed) but also how increased awareness can lead to decreases in diagnostic accuracy, to service overload, and how they may expose people to unnecessary or harmful treatments. We argue that the need for a framework founded on modelling societal dynamics is needed to ensure that both the benefits and the downsides of mental health information are accurately gauged and to help the planning of better public health campaigns.