Abstract
Purpose
The ability to correctly interpret quantitative results is a crucial skill developed in medical school and surgical residency. It demands a basic understanding of epidemiological principles and modes of presenting data. Yet, there has been little investigation into the efficacy of current teaching methods and areas of difficulty among orthopaedic residents.
Method
Forty orthopaedic residents attended a research course provided by the main author in preparation for this assessment. Immediately after formal teaching, these residents were administered a survey that assessed residents perceived and actual level of understanding of basic modes of presenting results including number needed to treat (NNT), relative risk (RR), odds ratio (OR), and absolute risk reduction (ARR). Residents were given a multiple choice clinical case scenario of fracture nonunion and asked to choose which result would be most efficacious at reducing nonunion. An All are equally efficacious option was given for each question. The multiple choice answers were purposefully identical with regard to effect size but answers differed in the way they were presented.
Results
Over 81% of residents agreed or strongly agreed that they had a good understanding of the modes of presenting results. However, less than 20% of residents consistently identified that the choices to questions were identical with regard to effect on nonunion rate. When the effect sizes in the choices were coupled with significant p-values (p < 0.05) of variable sizes, significantly fewer residents identified the correct solution (p < 0.05). Confidence intervals were associated with a decrement in correct responses (p < 0.05).
Conclusion
On average orthopaedic trainees have a poor understanding of presenting results and struggle to interpret them. Considerable confusion exists between measures of clinical significance and that of the effect size of treatment.
