Testing whether barriers to a hypothetical screening test affect unrelated perceived benefits and vice versa: A randomised, experimental study

OBJECTIVE: Determine whether (fictitious) health screening test benefits affect perceptions of (unrelated) barriers, and barriers affect perceptions of benefits. METHODS: UK adults were recruited via an online survey panel and randomised to receive a vignette describing a hypothetical screening test with either high or low benefits (higher vs. lower mortality reduction) and high or low barriers (severe vs. mild side-effects; a 2 × 2 factorial design). ANOVAs compared mean perceived benefits and barriers scores. Screening ‘intentions’ were compared using Pearson’s χ(2) test. RESULTS: Benefits were rated less favourably when barriers were high (mean: 27.4, standard deviation: 5.3) than when they were low (M: 28.5, SD: 4.8; p = 0.010, partial η(2) = 0.031). Barriers were rated more negatively when benefits were low (M: 17.1, SD: 7.6) than when they were high (M: 15.7, SD: 7.3; p = 0.023, partial η(2) = 0.024). Most intended to have the test in all conditions (73–81%); except for the low benefit-high barrier condition (37%; p < 0.0005; N = 218). CONCLUSIONS: Perceptions of test attributes may be influenced by unrelated characteristics. PRACTICE IMPLICATIONS: Reducing screening test barriers alone may have suboptimal effects on perceptions of barriers if benefits remain low; increasing screening benefits may not improve perceptions of benefits if barriers remain high.