"The worm in the radish doesn't think there is anything sweeter"

The Russian author and playwright Solomon Naumovich Rabinovich, better known by his pen name  Sholem Aleichem (the musical Fiddler on the Roof was based on several of his short stories) reportedly once said, "The worm in the radish doesn't think there is anything sweeter."  I don't know about you, but I happen to like radishes.  However, I also know that not everyone agrees with me!  As a matter of fact, radishes were used specifically for their poor taste (in this case relative to chocolate chip cookies) in a set of now classic experiments(see my post "What do I know of man's destiny? I could tell you more about radishes") on ego depletion by the psychologist Roy Baumeister.

Baumeister's study was originally published in the Journal of Personality and Social Psychology in 1998.  Basically, college students were told to fast for at least 3 hours before coming to Baumeister's psychology laboratory.  Upon entering the laboratory, the students immediately detected the aroma of freshly baked chocolate chip cookies.  Each student was told to sit at a table on which was placed two plates - a plate of chocolate chip cookies and a plate of radishes.  The laboratory team explained that the study was designed to test subjects' taste perception.  Each student was assigned to either the "cookie group" or the "radish group."  Students in the "cookie group" were told to eat at least 2-3 cookies but no radishes, while students in the "radish group" were told to eat at least 2-3 radishes but no cookies.  The laboratory staff then left the room and observed what happened through a one-way mirror.  After about 5 minutes, the laboratory staff re-entered the room and asked the student to complete a nearly impossible puzzle.  Students in the "cookie group" spent, on average, a total of 19 minutes on the puzzle before quitting.  Students in the "radish group", on the other hand, spent only 8 minutes on the puzzle before quitting.

Baumeister used these results in support of a concept he called ego depletion.  He believed that we all have a finite amount of self-control or willpower that we can rely upon in any situation.  Once we use up that self-control, we are more susceptible to a loss of control or willpower in a later situation.  Here, subjects that were told to eat the radishes and refrain from eating the cookies were using their willpower to follow the laboratory staff's admonition NOT to eat the cookie (they could have easily done so - no one was stopping them, right?).  Most of the students did, in fact, refrain from eating the cookies.  However, the mere act of refraining from eating the cookie used up all of their willpower.  So when they were faced with a more difficult cognitive task, they simply gave up.  It really doesn't take a lot of willpower to refrain from eating radishes, especially when you are told to eat the cookies.  Therefore, the students in the "cookie  group" still had enough willpower to persist for a longer period of time on the impossible puzzle.

Why am I talking about ego depletion and radishes?  As it turns out, a team of investigators from the University of Pennsylvania and the University of North Carolina applied this concept to hand hygiene (handwashing) in the hospital setting.  Their study, which was published in the Journal of Applied Psychology in 2015, collecting hand hygiene compliance data from 4,157 clinical staff (physicians, nurses, allied health professionals) working in 56 different inpatient units at 35 hospitals for a total of 13,772,922 unique hand hygiene opportunities.  Compliance was measured using radio frequency identification (RFID) technology on both entry and exit to and from a patient's room.  Overall hand hygiene compliance was poor (38%), consistent with other studies.  However, hand hygiene compliance dropped from 42.6% in the first hour to 34.8% during the last hour of a typical 12-hour shift.  The drop was even worse on higher intensity units (i.e., units with either more patients or sicker patients, where the workload was higher).  Longer breaks between shifts mitigated at least some of this decrease.  In other words, if clinicians were better rested at the start of their shifts, they were more likely to continue to maintain the same level of hand hygiene compliance from the start to the end of their shift.

What does all of this have to do with radishes?  As the investigators suggest in their paper, "Just as the repeated exercise of muscle leads to physical fatigue, repeated use of executive resources (cognitive resources that allow people to control their behaviors, desires, and emotions) produce a decline in an individual's self-regulatory capacity."  Similar to the concept of ego depletion, we all have a finite amount of capacity to follow standards, policies, and best practices.  If we are fatigued (say, towards the end of a busy shift with a lot of sick patients), we are less likely to be compliant with these standards and policies.  Given the importance of hand hygiene compliance in minimizing the spread of infections, these findings are of great interest to those of us in health care.  It would be interesting to see if compliance with other standards and policies similarly deteriorated over the course of a single shift in the hospital.  More importantly, it would be interesting to see if longer or more frequent breaks during a shift had any effect on maintaining compliance.