Using standardized patients (SP) is an excellent approach for performance evaluation in medical education. Effective SP programs require significant financial investment, which may prove difficult for many medical schools to provide. Ross University’s Advanced Introduction to Clinical Medicine Department uses teaching assistants (TA) as SPs in an effort to optimize resources.

Our hypothesis is that the use of  TAs who are medical school graduates as SPs influences the psychometrics of the examination, since their medical knowledge plays a role in the answers they give to random and unscripted student questions, thus influencing students’ decision making process.  

Use of medically trained faculty as SPs may impact the scoring of standardized patient encounters.

We need to consider other factors that may have impacted the results, such as TAs’ prior knowledge of each student’s abilities and differences in leniency among graders.

Although statistically significant, the small variance leads to the conclusion that future studies need to be conducted to clarify the benefit/risk ratio of using medical professionals as standardized patients.

Data was collected utilizing two groups of students and graders: the control group consisted of 135 students assigned to SPs and the study group consisted of 137 students assigned to TAs. Each instructor varied in group size, prompting standard deviation analysis for both groups prior to testing hypothesis.

Even though it may be more cost-effective to use the program’s own medical staff and avoid incurring the higher costs associated with a standardized patient program, the psychometric impact and grade accuracy should be considered.

We would like to akcnowledge Dean Flaherty's leadership and support of our research initiatives and Dr. Vivian Shayne's contribution to the statistical analysis.

Statistically significant differences were found through a one tail T- test. The test indicates the TA group scored students higher and had a smaller standard deviation than the SP group. 

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