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 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=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=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.