Context‐induced placebo effects—An investigation of contrast effects in response expectations and actual product efficacy

Recent research on the placebo effect of marketing actions has demonstrated that characteristics that are not inherent to a product's physical properties per se, such as its price, brand, or packaging can considerably shape consumers' expectations about and actual efficacy of a marketed product. However, potential contextual effects that other products may have on the construction of consumers' efficacy beliefs and objective consumption outcomes remain unexplored. Across two experimental studies, we show that people's response expectations regarding a focal product are inversely related to the alleged superiority of context options and that such context‐induced expectations can carry over to behavioural performance metrics; a phenomenon we refer to as context‐induced placebo effects.