@misc{10481/80143,
year = {2023},
month = {1},
url = {https://hdl.handle.net/10481/80143},
abstract = {Previous studies have shown that the price of a given product impacts the perceived quality of such product. This
finding was also observed in medical contexts, showing that expensive drugs increase the placebo effect compared
to inexpensive ones. However, addressing a drug’s efficacy requires making causal inferences between the drug and
the healing. These inferences rely on the contingency between these two events, a factor that is difficult to control
in the placebo research. The present study aimed to test whether the price of a given drug modulates its perceived
efficacy using a proper (though fictitious) non-effective drug, so that not only the objective contingency, but also
the probability of the cause and the probability of the effect could be adequately controlled for. We expected higher
efficacy judgements for the expensive non-effective drug than for the inexpensive one. To test this hypothesis, 60
volunteers participated in a contingency learning task that was programmed so that 72% of the patients healed
regardless of whether they took the drug. Approximately one-half of the participants were told that the drug was
expensive, whereas the other half were told that it was inexpensive. As expected, the efficacy judgements of participants
who saw the expensive drug were significantly higher than those who saw the inexpensive one. Overall, our
results showed that the price of a non-effective drug modulates its perceived efficacy, an effect that seems to be
mediated by the estimated number of doses administered. This result parallels findings in the placebo literature but
using a laboratory methodology that allows stronger control of the variables, suggesting that the illusory overestimation
produced by the more expensive treatments might be on the basis of the greater efficacy of the more expensive
placebos.},
organization = {Grant PID2021-126320NB-I00 from Agencia Estatal de Investigación of the Spanish Government},
organization = {Grant IT1696-22 from the Basque Government},
publisher = {Springer Nature},
keywords = {Medical decision making},
keywords = {Illusion of causality},
keywords = {Price},
keywords = {Drug efficacy},
keywords = {Alternative medicines},
title = {Expensive seems better: The price of a non‑effective drug modulates its perceived efficacy},
doi = {10.1186/s41235-023-00463-4},
author = {Díaz‑Lago, Marcos and Blanco Bregón, Fernando and Matute, Helena},
}