It is highly likely that there is a “placebo effect” present in EHM interventions. They have been widely demonstrated in medical treatment and prescription drugs, where clinical trials consciously include the identification of the extent of this effect. There have even been studies that confirm the “nocebo” effect, where instead of patients’ belief in a given intervention, by itself, having a measurable positive effect on the patient’s condition, belief in a risk or side effect tends to have a negative impact, even when no real intervention is used.

Some of the placebo effect may be the optimism that seems to be hard-wired into our brains, as demonstrated by a study finding that students who were pessimistic about getting good grades were far less likely to do so than those who were optimistic, with no other scientific explanation for this effect. [S. Wang “Optimism Comes Standard in Humans” Wall. St. Journal Health Blog Nov 9, 2007] It has been more thoroughly and scientifically examined in a book by Esther Sternberg, M.D., Chief, Section on Neuro-Endocrine Immunology & Behavior, National Institute of Mental Health — The Balance Within: The Science Connecting Health and Emotions Freeman 2001, particularly her chapter “Can Belief Make You Well?”.

Doctors have readily admitted to taking advantage of the placebo effect in treating their patients for ills, with 45% of respondents to a recent survey saying they had done so during their clinical practice. [J. Steenhuysen “Doctors Say Placebo Use Common” Yahoo! News Jan 3, 2008 (news.yahoo.com)] The fact that placebos are generally known to work, while having no negative effects, can make them preferable to medications with known such effects.

Whenever treatments or medications are used in employee health management (EHM), or in managing the health of other populations for that matter (PHM), it seems likely that the placebo effect will be part of any measured impact health management interventions have on participants therein. In a recent study by Harvard psychologist Ellen Langer, hotel maids, who spend the majority of their days engaged in pushing equipment around, making beds, and other physical activity, were told that their work activity already exceeded the Surgeon General’s definition of an active lifestyle.

This was news to the majority of maids so informed, among whom 67% had reported themselves as “not exercising”. Half of the maids in the study were given the information about their current activity already meeting exercise standards, while half were not told, as “controls”. Among those told, there was a measured 10% drop in blood pressure, as well as reduced weight and waist/hip ratio. And there had been no indication that the maids had altered their routine in any way. Apparently, merely believing that their “exercise” would enable them to be healthier made it so. [A. Spiegel “Hotel Maids Challenge the Placebo Effect” National Public Radio Jan 4, 2008]

There is a much older demonstration of an equivalent placebo effect in a 1927 study of improving the lighting where workers performed at the Hawthorne Works of Western Electric Co. in Cicero, Illinois. IT found that “controls” improved their performance, despite having no changes at all made in their working conditions, as well as the “intervention group” improving theirs. This has been labeled the “Hawthorne Effect” and is normally analyzed in scientific, controlled studies of management interventions.

It is rare for any employer or even insurer to include controls in their studies of the effectiveness of EHM or PHM, but if participants in a given intervention know about the study, there may be some. It has never been clear precisely what causes the Hawthorne Effect. It may have been, for example, that workers were unconsciously or consciously affected by the fact that their performance was being measured, fearing that they might look bad if they did not make extra effort. Or merely knowing that their employer was doing something to improve rather than ignore their working conditions might have given them a more positive feeling about their employer, and caused an improvement in effort as a result.

Both such effects may well be present in EHM, where employees may have either or both reactions and responses to the measurement of their performance and their employers’ sponsorship of an effort to improve their health. It seems less likely to apply to insurer-sponsored PHM aimed at reducing healthcare use, since that is likely to be seen as self-serving for the insurer by participants, but I know of no studies investigating such an effect.

The amount of measured placebo effect is traditionally used to discount the effects of therapies and medications on patients in sickness care. If the placebo control group has a 43% improvement in some clinical measure, while the actual treatment group has a 75% improvement, the treatment is deemed to be responsible for only 75 minus 43 = 32% of the effect.

In EHM, however, where the effect is more likely, it makes sense to gladly accept the placebo effect as a positive and economically beneficial part of the intervention, especially since “controls” can rarely be given a true placebo, except in such cases as nicotine replacement therapy, where a placebo may help smokers quit, as well as the drug used. Rather, the placebo or Hawthorne effect, whichever applies, is a genuine part of the effect of the intervention in its broader sense.

Of course, the employer may choose to partially discount the results achieved by the EHM provider it hires for the job, if there are indications that a placebo/Hawthorne effect is present, since it is the employer, rather than the supplier that may be responsible for at least part of this effect, as sponsor of vs. provider of the intervention. There are also likely to be added effects caused by employees knowing about their health risks, even if they enroll in no intervention aimed at reducing them.

The HRA (health risk assessment) performed on most employees includes feedback to each who completes it, which may cause effects on its own, for employees (plus) dependents/retirees who get recommendations for improving their health, without any program participation. The data are unclear on this effect, with some studies indicating that HRA participants, by that act alone, have lower medical care costs than non-participants, while others indicate that HRA participants that do not follow up this act by engaging in an EHM intervention, end up with higher risks and lower productivity.

In any case, the placebo/Hawthorne/information effects in EHM can be readily identified by comparing those who do not participate in the HRA or an EHM intervention against those who do, on before vs. after healthcare, workers compensation, disability, and productivity impairment costs, compared to those who take the HRA but no intervention, and to those who take the intervention as well as the HRA.

This will enable identifying the probable inclusion of such effects in the results found, though the HRA and EHM participation effects can logically be accepted as true results of the intervention. And the economic benefits of such efforts are usually so much more than the costs thereof, that the credit can easily be shared between both the employer and the HRA plus EHM suppliers, where they are different.