The impact of psycho-social factors on the effectiveness of heat warning systems

摘要

Background Health behavior/promotion theories and studies confirm that the effectiveness of health messages in changing behaviors greatly relies on socio-demographic, cognitive and emotive factors. Many countries have implemented heat warning systems (HWS) to minimize health risks, particularly among vulnerable groups. Studies suggest that these systems reduce mortality; however their effectiveness and impact on changing people's behavior against heat harm is unclear. Aims To review the literature on psychosocial factors that can hamper or improve the effectiveness of HWS in saving lives and reducing harm. Methods A systematic search of major databases was conducted with keywords "heat, heatwave, high temperature, hot temperature, OR hot climate" AND "warning OR alert system". Results Only eight relevant studies were found- USA (3), Canada (2), UK (2), Australia (1). All were retrospective and, except two, lacked a theoretical model to guide the research. Ethnic minorities were mostly excluded. The findings suggested that participants were overall cognisant of heat warnings through various media. However, they did not necessarily act on these messages.They were more likely to take actions (e.g. light dress, hydration, cooling) to protect themselves or others against heat dangers if they perceived it to be a threat (emotive factor). Issues such as costs of running air-conditioners or accessing cooling shelters were reported to act as barriers particularly to the poor exposing them to heat harms. Conclusions Warning messages may reach people, but are not always translated into action because of attitudinal, socio-demographic and cost factors. Attention to these should improve HWS' effectiveness. Research in this area is very limited. Prospective studies applying health behavior/promotion theories should identify vulnerable groups (e.g. homeless, people with language difficulties, elderly) and investigate the specific ways in which HWS can produce the health benefits they are purported to achieve among these groups.