Chris Aitchison

and 4 more

Background: Whilst core curricula in neurology are nationally standardised, in real-world clinical practice, different approaches may be taken by individual consultants. In this study, we investigated: (1) variance in diagnostic and investigative practice, using a case-based analysis of inter-rater agreement; (2) potential importance of any differences in terms of patient care; (3) relationships between clinical experience, diagnostic certainty, diagnostic peer-agreement and investigative approach; (4) development of novel individualised metrics to facilitate appraisal. Methods: Four neurologists with 0-23 years’ experience at consultant level provided diagnosis, certainty (10-point Likert scale), and investigative approach for 200 consecutive general neurology outpatients seen by a newly qualified consultant. Diagnostic agreement was evaluated by percentage agreement. The potential importance of any diagnostic differences was assigned a score by the evaluating neurologist (6-point Likert scale). Associations between diagnostic agreement, certainty and investigative approach were assessed using Spearman correlation, logistic and ordinal regression, and reported as individualiszd metrics for each rater. Results: Diagnostic peer-agreement was 4/4, 3/4, 2/4 and 1/4 in 50%, 28%, 20% and 3% of cases, respectively. In 17%, differences in patient management were judged potentially important. Investigation rates were 42-73%. Mean diagnostic certainty ranged between 6.2/10 (SD 2.1) to 7.7/10 (SD 2.2) between least and most experienced consultants. Greater diagnostic certainty was associated with greater diagnostic peer-agreement (individual-rater regression coefficients 0.30-0.51, p<0.01) and lower odds of arranging investigations (individual-rater odds ratios 0.58-0.78, p<0.01). Conclusions: Variance in diagnostic and investigative practice between consultant neurologists exits and may result in differing management. Mean diagnostic certainty increased numerically with experience and was statistically associated with greater diagnostic peer-agreement and lower investigation rates. Metrics reflecting concordance with peers, and relationships to diagnostic confidence, could inform reflective practice.