Factors influencing intention to undergo whole genome screening in future healthcare: a single-blind parallel-group randomised trial

Objective This study investigated the effect of biased information on beliefs about, and intention to undergo, whole genome sequencing (WGS) screening; and predictors of intention. Methods A single-blind parallel-group randomised trial was conducted in Australia, in 2011. Using Excel, 216 participants with English proficiency and no genetic testing experience were randomly allocated (1:1): a neutral information pamphlet or a biased version omitting screening limitations. Measures included: screening intention; Protection Motivation Theory (PMT) constructs; consideration of future consequences (CFC); uncertainty avoidance (UA); anticipated regret (AR). Results Intention decreased from pre to post‐manipulation (p < .001, η2 = .07, 95% CIs [4.41, 4.86], [3.99, 4.44], respectively). Biased participants (n = 106) had higher response efficacy beliefs than neutral participants (n = 102) (p < .001, η2 = .04, 95% CIs [4.80, 5.10], [4.49, 4.79] respectively), but equal intention. The model explained 36.2% of the variance in intention; response efficacy (p < .001), response costs (p < .001), self-efficacy (p = .024), and UA (p = .019) were predictors. Conclusion This is the first study investigating factors influencing anticipated WGS screening uptake. Omitting screening limitations may bias beliefs about screening efficacy and benefits. Uptake may be driven by perceived benefits and costs, self-efficacy beliefs, and uncertainty avoidance. PMT appears to be an appropriate psychosocial model for this setting.