Abstract:
The nocebo effect is a powerful phenomenon with important implications in healthcare. Social modelling is one of the influencing mechanisms of the nocebo effect. Nocebo responses have been observed following news reports on side effects about medication formulation changes, and switches from branded to generic medicines.
The objective of this study was to investigate whether social modelling is a mechanism behind the news media's influence over nocebo responding. The study examined whether a television news bulletin, with patients discussing experiences with a medication, increased the number of symptoms that were attributed to a placebo nose spray to a greater degree than a journalist-only news bulletin, or a leaflet control. The study was a between subjects experimental design. Fifty-nine participants were recruited, and completed baseline measurements of demographics, symptoms experienced in the past week, fatigue, alertness, anxiety, and a choice reaction time task. Participants were randomly allocated into one of three conditions: the news bulletin with social modelling condition, the news bulletin without social modelling condition, and the leaflet control condition. Each group received different versions of the same information about the medication they would take. Prior to their treatment, expectations and anxiety levels were measured. Following medication administration, symptoms and side effects were measured, as well as levels of alertness and
fatigue, and the choice reaction time task. Forty-eight hours later participants again reported any symptoms or side effects they had experienced since taking the drug. Contrary to predictions, participants in the news bulletin without social modelling condition attributed significantly more symptoms as side effects compared to participants in
the news bulletin with social modelling condition and the leaflet control condition. This provides evidence that a nocebo effect occurred, with the journalist-only news bulletin having the largest effect on side effect reporting. Participants in both video conditions expected side effects after taking modafinil compared to the leaflet condition. A placebo effect with lower fatigue and greater alertness was found across all three groups but was again most evident in the news bulletin without social modelling condition. These results suggest that the journalist-only condition, without social modelling, provided more credible and powerful information about the medication, leading to media-induced nocebo effects.