From BMJ, The survival time of chocolates on hospital wards: covert observational study.
Objective To quantify the consumption of chocolates in a hospital ward environment.
Design Multicentre, prospective, covert observational study.
Setting Four wards at three hospitals (where the authors worked) within the United Kingdom.
Participants Boxes of Quality Street (Nestlé) and Roses (Cadbury) on the ward and anyone eating these chocolates.
Intervention Observers covertly placed two 350 g boxes of Quality Street and Roses chocolates on each ward (eight boxes were used in the study containing a total of 258 individual chocolates). These boxes were kept under continuous covert surveillance, with the time recorded when each chocolate was eaten.
Main outcome measure Median survival time of a chocolate.
Results 191 out of 258 (74%) chocolates were observed being eaten. The mean total observation period was 254 minutes (95% confidence interval 179 to 329). The median survival time of a chocolate was 51 minutes (39 to 63). The model of chocolate consumption was non-linear, with an initial rapid rate of consumption that slowed with time. An exponential decay model best fitted these findings (model R2=0.844, P<0.001), with a survival half life (time taken for 50% of the chocolates to be eaten) of 99 minutes. The mean time taken to open a box of chocolates from first appearance on the ward was 12 minutes (95% confidence interval 0 to 24). Quality Street chocolates survived longer than Roses chocolates (hazard ratio for survival of Roses v Quality Street 0.70, 95% confidence interval 0.53 to 0.93, P=0.014). The highest percentages of chocolates were consumed by healthcare assistants (28%) and nurses (28%), followed by doctors (15%).
Conclusions From our observational study, chocolate survival in a hospital ward was relatively short, and was modelled well by an exponential decay model. Roses chocolates were preferentially consumed to Quality Street chocolates in a ward setting. Chocolates were consumed primarily by healthcare assistants and nurses, followed by doctors. Further practical studies are needed.
This summer at several West Michigan health care facilities we conducted our own research. A blue tray with three shallow compartments was periodically filled with individually wrapped chocolates and placed at the nurses station. By removing the barrier of a closed box or bag, we found consumption rates greatly accelerated. All three shifts were evaluated, both during the week and on weekends.
Surprisingly, based on reporting from the aides, the longest survival times were during third shift, provided that the chocolates were placed AFTER the overlap with second shift. Otherwise the chocolates experienced a mass extinction event. The best explanations for the third shift results are: (1) third shift aides brought their own snacks and (2) they frequently didn't have time to stand around the nurses station. One would think that things would quiet down in the wee hours, but the middle of the night often is when patients need the most care. Also, second shift experiments had the shortest half-life and lifetime results.
Nurses seemed to consume the least, though doctors reporting on the floor was negligible -- too low to count. Selected aides were shown where the bags of chocolates were kept, For Emergency Purposes, but they almost never took advantage of this information. A separate study on will power versus opportunity (in a drawer in a cupboard versus out in the open) is clearly required. The tray was never returned immediately upon emptying, but usually days later, often by another shift. When first testing a ward, a learning cycle had to be achieved where the tray had to be manually retrieved, rather than automatically.
Also, the lifetimes of chocolates, from shortest to longest, include Dove miniatures, Hershey Select miniatures (gold and silver foils, with and without nuts) and Hershey miniatures (krackel, Mr. Goodbar, milk chocolate and Special Dark). For Fourth of July we had red and blue foil Doves and silver foil Hershey Kisses arranged in the three bins as red, white and blue.
By the way, the LJ/DW icon I used on this post is Kate Winslet holding a Lifesaver in her mouth -- it is, I believe, the only one of my 227 icons which features candy.