The term placebo comes from the Latin version of Psalm 116:9: “placebo Domino in regione vivorum” or “I will please the Lord in the land of the living”. It has become part of modern English through the observation that sometimes a inert treatment given in substitute for the active one, such as a sugar pill rather than a new drug, can appear to be just as efficacious (and thus present an apparently pleasing result). If a treatment can’t show a marked improvement compared to placebos in trials then it won’t be developed through to the point of routine usage. Recent reports, highlighted this week by the BBC, suggest that this lack of advantage of placebos seems to be an upward trend.
How can that be? One option would be that too many people are getting onto trials despite not stringently meeting the inclusion criteria (or those criteria being too fuzzy in the first place). That could be because patients are keen to sign up for trials (believing they are getting cutting edge treatment and certainly getting above average care and attention), that trail centres are pressured to meet recruitment targets within short time frames or, for a very paranoid twist, that pharmaceutical companies want their drugs to appear to be more effective. That isn’t working out so well now that the placebo effect is shown to be rising but could have been a multi-million dollar strategy in the past. Even aside from out and out skullduggery, trials do work under financial constraints and those may influence those running them.
It could be that we are struggling to come up with more effective treatments. Perhaps we have already discovered most of the easy wins about how to fix problems with our health and so it is less likely that a novel solution is genuinely effective. It might be possible to test for this by looking not only at treatment vs placebo but also the balance of benefit vs no benefit over time. I haven’t thoroughly read the literature to see if anyone has taken that angle but, if not, I’d be very happy to help you develop the paper and join the credits if you want to research and publish!
Thirdly, we could be becoming more gullible or at least so overwhelmed by information that it is hard to notice if the treatment isn’t having an effect and thus positive thinking wins out. There is certainly some role for mind over matter in ongoing health, even if just to reduce the stress and anxiety which seem to inhibit healing.
Or, as my final snowflake in this blizzard of thoughts, perhaps we are simply getting better at running trials and analysing the statistics and so we are able to more clearly to discern the role of placebo effect in the output?