Prospective memory failures as an unexplored threat to patient safety: results from a pilot study using patient simulators to investigate the missed execution of intentions

Abstract

This study investigated failures of prospective memory (PM) as a relevant but neglected error type in medicine. A patient simulator was used to investigate PM failures. The influence of subjective importance (high, low) and type of intention (educational, internal, external) on the (missed) execution of intention was investigated in a 2 × 2 design. The effects on missed executions by importance (high < low) and type of intention (educational < external < internal) were hypothesized. Of 73 valid intentions in 40 prepared simulator scenarios 19 (26%) were missed overall. A total of 64% of unimportant and 80% of important intentions were executed 79% of educational 67% of external and 72% of internal intentions were executed. Neither difference was statistically significant using χ² tests. Interaction was significant for missed executions (p = 0.025; n = 19; df = 2; χ² = 7.41) and for executions (p = 0.002; n = 54; df = 2; χ² = 12.50). Despite low statistical support and some methodological limitations, it was possible to show that PM failures are relevant to patient safety and that patient simulators are a suitable but so far unused tool for their investigation.

Keywords:

• Prospective memory
• Patient safety
• Simulation
• Human error

Acknowledgements

This research was funded by the ‘Fortune’ programme of the University of Tuebingen Medical School (Project-No. 1151–0-0). We are grateful to this programme for allowing us to begin the systematic study of PM failures in the medical field. Additional resources were granted by the Center for Organisational and Occupational Sciences of the Swiss Federal Institute of Technology (ETH) in Zurich. Many thanks to our participants who allowed us to collect the data and the anonymous reviewers who helped with their comments to improve the original manuscript. We thank our colleague Bertram Schaedle, our co-instructors and nurses in the team for running the simulations. Thanks to Joerg Zieger, who also ran scenarios and helped to sharpen our definition of PM and its failures. Thanks to David Gaba, Stanford, for stimulating many thoughts and reminding us not to forget our PM project.