Any serious discussion of preventive intervention targeting neuroticism also must consider other possible negative iatrogenic effects. Because wide-spread preventive interventions to reduce neuroticism might even have the unintended effect of reducing adaptive levels of fearfulness and wariness to unsafe levels in some persons, care would need to be taken. This concern might be minimized by intervening only with persons with high levels of neuroticism who requested the intervention, but in some dangerous environments in which cues signaling danger are subtle, such as some urban environments, even relatively high levels of neuroticism might be adaptive in some cases (Matthews et al., 2003).
