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The case of the disappearing teaspoons: longitudinal cohort study of the displacement of teaspoons in an Australian research institute

BMJ 2005; 331 doi: (Published 22 December 2005) Cite this as: BMJ 2005;331:1498
  1. Megan S C Lim, research assistant1,
  2. Margaret E Hellard, director1,
  3. Campbell K Aitken (aitken{at}, senior research officer1
  1. 1 Centre for Epidemiology and Population Health Research, Macfarlane Burnet Institute for Medical Research and Public Health, GPO box 2284, Melbourne, Victoria, 3001, Australia
  1. Correspondence to: C K Aitken
  • Accepted 9 October 2005


Objectives To determine the overall rate of loss of workplace teaspoons and whether attrition and displacement are correlated with the relative value of the teaspoons or type of tearoom.

Design Longitudinal cohort study.

Setting Research institute employing about 140 people.

Subjects 70 discreetly numbered teaspoons placed in tearooms around the institute and observed weekly over five months.

Main outcome measures Incidence of teaspoon loss per 100 teaspoon years and teaspoon half life.

Results 56 (80%) of the 70 teaspoons disappeared during the study. The half life of the teaspoons was 81 days. The half life of teaspoons in communal tearooms (42 days) was significantly shorter than for those in rooms associated with particular research groups (77 days). The rate of loss was not influenced by the teaspoons' value. The incidence of teaspoon loss over the period of observation was 360.62 per 100 teaspoon years. At this rate, an estimated 250 teaspoons would need to be purchased annually to maintain a practical institute-wide population of 70 teaspoons.

Conclusions The loss of workplace teaspoons was rapid, showing that their availability, and hence office culture in general, is constantly threatened.


  • Embedded Image Details of the statistical analysis and study limitations are on

  • Contributors All authors contributed to the conception, design, and management of the study and to the preparation of the manuscript. MSCL collected the data, which were analysed by all authors. CKA is guarantor.

  • Competing interests None declared.

  • Ethical approval Our study was approved by the director of the Burnet Institute.

  • Accepted 9 October 2005
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