An experimental test to reveal negative side-effects of high treatability information on preventative health behaviour.

Objectives. When the course of a disease can be positively changed by health professionals the disease can be indicated as ‘highly treatable’. This ‘high treatability information’ (HTI) may have negative side-effects on people’s preventative motivation. This study examined the effects of HTI regarding skin cancer on preventative motivation.

Design. This study employed a 2(high treatability(HTI) versus low treatability(LTI)) × 2(high versus low susceptibility)-experiment with a hanging control group. (family) History and self-efficacy were assessed as moderators.

Participants (N =309) were randomly assigned to one of the five conditions. Main outcome measures. The main outcome was intention to engage in preventative actions regarding skin cancer. Results. HTI significantly lowered the intention compared to LTI, under the condition of high susceptibility in people with low self-efficacy. In addition, in people with a (family) history of skin cancer, HTI significantly lowered the intention compared to the no-information group.

Conclusion. HTI regarding skin cancer can cause a drop in the preventative motivation. The effects can be conceptualized as negative side-effects of HTI. As substantial proportions of the general population have a (family) history of skin cancer or low self-efficacy, the side-effects may be widespread, possibly increasing the incidence of skin cancer.