Nurses' risk assessment judgements: a confidence calibration study

J Adv Nurs. 2010 Dec;66(12):2751-60. doi: 10.1111/j.1365-2648.2010.05437.x. Epub 2010 Sep 6.


Aim: This paper is a report of a study of the relationship between nurses' clinical experience and calibration of their self-confidence and judgement accuracy for critical event risk assessment judgements.

Background: Miscalibration (i.e. under-confidence or over-confidence of confidence levels) has an important impact on the quality of nursing care. Despite this, little is known about how nurses' subjective confidence is calibrated with the accuracy of their judgments.

Methods: A sample of 103 nursing students and 34 experienced nurses were exposed to 25 risk assessment vignettes. For each vignette they made dichotomous judgements of whether the patient in each scenario was at risk of a critical event, and assigned confidence ratings (0-100) to their judgement calls. The clinical vignettes and judgement criteria were generated from real patient cases. The methodology of confidence calibration was used to calculate calibration measures and generate calibration curves. Data were collected between March 2007 and January 2008.

Findings: Experienced nurses were statistically significantly more confident than students but no more accurate. Whilst students tended towards under-confidence, experienced nurses were over-confident. Experienced nurses were no more calibrated than students. Experienced nurses were no better at discriminating between correct and incorrect judgements than students. These patterns were exacerbated when nurses and students were extremely over-confident or extremely under-confident.

Conclusion: Nurses were systematically biased towards over/under-confidence in their critical event risk assessment judgements. In particular, experienced nurses were no better calibrated than their student counterparts; with student under-confidence countered by experienced nurses' greater susceptibility to over-confidence.

MeSH terms

  • Adult
  • Attitude of Health Personnel*
  • Calibration
  • Clinical Competence / standards*
  • Data Interpretation, Statistical
  • Decision Making
  • Female
  • Humans
  • Male
  • Nurses / psychology*
  • Nursing Research
  • Risk Assessment / standards*
  • Self Concept*
  • Students, Nursing / psychology*