Physical activity, a balanced diet, avoidance of tobacco exposure, and limited alcohol consumption may reduce morbidity and mortality from non-communicable diseases (NCDs). Mass media interventions are commonly used to encourage healthier behaviours in population groups. It is unclear whether targeted mass media interventions for ethnic minority groups are more or less effective in changing behaviours than those developed for the general population.
To determine the effects of mass media interventions targeting adult ethnic minorities with messages about physical activity, dietary patterns, tobacco use or alcohol consumption to reduce the risk of NCDs.
We searched CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, ERIC, SweMed+, and ISI Web of Science until August 2016. We also searched for grey literature in OpenGrey, Grey Literature Report, Eldis, and two relevant websites until October 2016. The searches were not restricted by language.
We searched for individual and cluster-randomised controlled trials, controlled before-and-after studies (CBA) and interrupted time series studies (ITS). Relevant interventions promoted healthier behaviours related to physical activity, dietary patterns, tobacco use or alcohol consumption; were disseminated via mass media channels; and targeted ethnic minority groups. The population of interest comprised adults (≥ 18 years) from ethnic minority groups in the focal countries. Primary outcomes included indicators of behavioural change, self-reported behavioural change and knowledge and attitudes towards change. Secondary outcomes were the use of health promotion services and costs related to the project.
Two authors independently reviewed the references to identify studies for inclusion. We extracted data and assessed the risk of bias in all included studies. We did not pool the results due to heterogeneity in comparisons made, outcomes, and study designs. We describe the results narratively and present them in 'Summary of findings' tables. We judged the quality of the evidence using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology.
Six studies met the inclusion criteria, including three RCTs, two cluster-RCTs and one ITS. All were conducted in the USA and comprised targeted mass media interventions for people of African descent (four studies), Spanish-language dominant Latino immigrants (one study), and Chinese immigrants (one study). The two latter studies offered the intervention in the participants' first language (Spanish, Cantonese, or Mandarin). Three interventions targeted towards women only, one pregnant women specifically. We judged all studies as being at unclear risk of bias in at least one domain and three studies as being at high risk of bias in at least one domain.We categorised the findings into three comparisons. The first comparison examined mass media interventions targeted at ethnic minorities versus an equivalent mass media intervention intended for the general population. The one study in this category (255 participants of African decent) found little or no difference in effect on self-reported behavioural change for smoking and only small differences in attitudes to change between participants who were given a culturally specific smoking cessation booklet versus a booklet intended for the general population. We are uncertain about the effect estimates, as assessed by the GRADE methodology (very low quality evidence of effect). No study provided data for indicators of behavioural change or adverse effects.The second comparison assessed targeted mass media interventions versus no intervention. One study (154 participants of African decent) reported effects for our primary outcomes. Participants in the intervention group had access to 12 one-hour live programmes on cable TV and received print material over three months regarding nutrition and physical activity to improve health and weight control. Change in body mass index (BMI) was comparable between groups 12 months after the baseline (low quality evidence). Scores on a food habits (fat behaviours) and total leisure activity scores changed favourably for the intervention group (very low quality evidence). Two other studies exposed entire populations in geographical areas to radio advertisements targeted towards African American communities. Authors presented effects on two of our secondary outcomes, use of health promotion services and project costs. The campaign message was to call smoking quit lines. The outcome was the number of calls received. After one year, one study reported 18 calls per estimated 10,000 targeted smokers from the intervention communities (estimated target population 310,500 persons), compared to 0.2 calls per estimated 10,000 targeted smokers from the control communities (estimated target population 331,400 persons) (moderate quality evidence). The ITS study also reported an increase in the number of calls from the target population during campaigns (low quality evidence). The proportion of African American callers increased in both studies (low to very low quality evidence). No study provided data on knowledge and attitudes for change and adverse effects. Information on costs were sparse.The third comparison assessed targeted mass media interventions versus a mass media intervention plus personalised content. Findings are based on three studies (1361 participants). Participants in these comparison groups received personal feedback. Two of the studies recorded weight changes over time. Neither found significant differences between the groups (low quality evidence). Evidence on behavioural changes, and knowledge and attitudes typically found some effects in favour of receiving personalised content or no significant differences between groups (very low quality evidence). No study provided data on adverse effects. Information on costs were sparse.
The available evidence is inadequate for understanding whether mass media interventions targeted toward ethnic minority populations are more effective in changing health behaviours than mass media interventions intended for the population at large. When compared to no intervention, a targeted mass media intervention may increase the number of calls to smoking quit line, but the effect on health behaviours is unclear. These studies could not distinguish the impact of different components, for instance the effect of hearing a message regarding behavioural change, the cultural adaptation to the ethnic minority group, or increase reach to the target group through more appropriate mass media channels. New studies should explore targeted interventions for ethnic minorities with a first language other than the dominant language in their resident country, as well as directly compare targeted versus general population mass media interventions.