Mass media interventions for reducing mental health-related stigma.
Level 1 - systematic review of randomized trials
Systematic review of randomized controlled trials
PubMed 23881731 · doi:10.1002/14651858.CD009453.pub2
What was done
Authors searched 11 electronic databases through August 2011 (with select sources searched to August 2012) alongside grey literature, conference abstracts, and reference lists. They included randomized controlled trials, cluster randomized trials, and interrupted time series evaluating mass media interventions compared to inactive controls in general public populations for mental health-related discrimination or prejudice. Two authors independently extracted data and assessed risk of bias. Primary outcomes were discrimination and prejudice; secondary outcomes included knowledge, costs, reach, recall, sustainability, and adverse effects. Synthesis was predominantly narrative due to substantial heterogeneity.
What was found
Twenty-two randomized trials (including 3 cluster RCTs) involving 4,490 participants were included; 19 trials had analysable data, and 17 studied student populations. For discrimination (5 trials, n = 1,196), findings were mixed: three trials with continuous measures (n = 394) had a median standardized mean difference (SMD) of -0.25 (range: -0.85 [95% CI -1.39 to -0.31] to -0.17 [95% CI -0.53 to 0.20]), and two trials with dichotomous measures (n = 802) showed odds ratios of 1.30 (95% CI 0.53 to 3.19) and 1.19 (95% CI 0.85 to 1.65). For prejudice (19 trials, n = 3,176), median SMDs favored the intervention: -0.38 immediately, -0.38 at 1 week to 2 months, and -0.49 at 6 to 9 months (individual trial SMDs ranged from -2.94 [95% CI -3.52 to -2.37] to 2.40 [95% CI 0.62 to 4.18]). Cost data (3 studies, n = 416) were variable without cost-effectiveness evaluation. Two studies (n = 455) reported on adverse effects and found none.
Why it matters
Mass media campaigns may achieve small to medium reductions in prejudice and stigmatising attitudes toward mental illness, but evidence remains insufficient to confirm whether they reduce actual discriminatory behavior.
Limits
Evidence certainty was rated low for prejudice, discrimination, and adverse effects, and very low for costs. Most included studies had an unclear or high risk of bias across multiple domains. Seventeen of 22 studies evaluated student samples, few took place in low- or middle-income countries, and none evaluated children, adolescents, employers, or healthcare professionals.