Kantonsspital St.Gallen
login

Black medicine: an observational study of doctors' coffee purchasing patterns at work

Karlmeinrad Giesinger, David F Hamilton, Matthias Erschbamer, Bernhard Jost & Johannes M Giesinger

abstract

OBJECTIVE
 To evaluate doctors' coffee consumption at work and differences between specialties.

DESIGN
 Single centre retrospective cohort study.

SETTING
 Large teaching hospital in Switzerland.

PARTICIPANTS
 766 qualified doctors (425 men, 341 women) from all medical specialties (201 internal medicine, 76 general surgery, 67 anaesthetics, 54 radiology, 48 orthopaedics, 43 gynaecology, 36 neurology, 23 neurosurgery, 96 other specialties).

DATA SOURCE
 Staff purchasing history from staff canteens' electronic payment system linked to separate anonymised personal data from the human resource database.

MAIN OUTCOME MEASURE
 Numbers of coffees purchased per person per year.

RESULTS
 84% (644) of doctors purchased coffee at one of the hospital canteens. 70 772 coffees were consumed by doctors in 2014. There was a significant association between specialty and yearly coffee purchasing (F=12.45; P<0.01). On average orthopaedic surgeons purchased the most coffee per person per year (mean 189, SD 136) followed by radiologists (177, SD 191) and general surgeons (167, SD 138). Anaesthetists purchased the least coffee (39, SD 48). Male doctors bought significantly more coffees per person per year (128 (SD 140) v 86 (SD 86), t=-4.66, P<0.01) and twice as many espressos as female doctors (mean 27 (SD 46) v 10 (SD 19), t=-6.54, P<0.01). Hierarchical position was associated with coffee purchasing (F=4.55; P=0.04). Senior consultants (>5 years' experience) bought most coffees per person per year (140, SD 169) and junior doctors and registrars bought fewest (95, SD 85). Propensity of buying rounds also increased with hierarchical position (χ(2)=556.24; P<0.01), with heads of departments buying more rounds than junior doctors (30% v 15%).

CONCLUSIONS
 Doctors commonly use coffee as a stimulant. Substantial variation exists between specialties. Surgeons drink notably more coffee than physicians, with orthopaedic surgeons consuming the greatest amount in the communal cafeteria setting, though this might reflect social tendencies rather than caffeine dependency. Hierarchical position is positively correlated with coffee consumption and generosity with regard to buying rounds of coffee.
   
citation Giesinger K, Hamilton D F, Erschbamer M, Jost B, Giesinger J M. Black medicine: an observational study of doctors' coffee purchasing patterns at work. BMJ 2015; 351:h6446.
   
type journal paper/review (English)
date of publishing 16-12-2015
journal title BMJ (351)
ISSN electronic 1756-1833
pages h6446
PubMed 26676463