Inducing System-1-type diagnostic reasoning in second-year medical students within 15 minutes

Abstract

Purpose: Diagnostic reasoning literature debates the significance of “dual-process theory” and the importance of its constituent types of thinking: System-1and System-2. This experimental study aimed to determine whether novice medical students could be trained to utilize System-1 thinking when making diagnoses based on chest X-rays.

Method: Second-year medical students were recruited and presented with a series of eight online chest X-rays cases. Participants were shown half of the cases repeatedly during a training phase and the other half only twice. During the final test phase, they were shown all eight cases, providing a diagnosis as a free text answer. Dependent variables were diagnostic accuracy and response time.

Results: Thirty-two students participated. During the test phase, students responses were significantly more accurate and faster for cases which had been seen repeatedly during the training phase (mean score = 3.56/4, mean time = 2.34 s) compared with cases which had been seen only twice (mean score = 1.59/4, mean time = 7.50 s).

Conclusion: This study demonstrates that it is possible to induce in novice students the speed-to-diagnosis and diagnostic accuracy typical of System-1-type reasoning. The full experimental design and the chest X-rays used may provide new opportunities to explore some of the issues surrounding dual-process theory.

Acknowledgments

The authors would like to thank Ms. Mabel Tang for her support in preparing the materials for this study.

Ethical approval

This study received ethical approval IRB-2016-01-015 from the Institutional Review Board (IRB) of Nanyang Technological University, Singapore.

Previous presentations

Rosby L, Rotgans J, Tan GJS, Low-Beer N, Schmidt HG. Diagnostic performance in novice medical students: use of a novel study design to investigate the impact of online training. Winner of the ‘Best Abstract for Poster Presentation’ category at 14th Asia-Pacific Medical Education Conference (APMEC), Singapore, 13–14 January 2017.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Glossary

Dual-process theory: Dual-process theory is one of the theories explaining how doctors make decisions about diagnoses (Croskerry 2009). This theory proposes two constituent types of thinking: System-1 and System-2. System-1 is fast, intuitive, automatic, and requires minimal effort (Evans 2008) allowing clinicians to make diagnoses based on stored “illness scripts” or exemplars and pattern recognition (Charlin et al. 2007) whereas System-2 is slow, deliberate, conceptual, and systematic (Evans 2008).

Notes on contributors

Dr Lucy Victoria Rosby, MBBS, MSc, is Senior Lecturer, Office of Medical Education, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Dr Jerome I. Rotgans, PhD, is Assistant Professor, Medical Education Research and Scholarship Unit, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Dr Gerald Tan, MBBS, is Consultant Radiologist, Tan Tock Seng Hospital, Singapore and Adjunct Assistant Professor, Office of Medical Education, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Dr Naomi Low-Beer, MBBS, MD, is Vice-Dean Education, Office of Medical Education, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Dr Silvia Mamede, MD, PhD, is Associate Professor, Institute of Medical Education Research Rotterdam, Erasmus Medical Center, Rotterdam, The Netherlands.

Dr Laura Zwaan, PhD, is Assistant Professor, Institute of Medical Education Research Rotterdam (iMERR), Erasmus Medical Center, Rotterdam, The Netherlands.

Dr Henk Schmidt, PhD, is Professor of Medical Education and Professor of Psychology, Erasmus University Rotterdam, the Netherlands.

Additional information

Funding

The study was funded by a National Research Foundation (NRF) Planning grant [NRF2015-SOL001-013)].  Dr. Zwaan is supported by the Netherlands Organization for Scientific Research [NWO-VENI grant nr: 451-16-032].