Although ECG interpretation has cemented itself as a core competency in modern medicine, many practitioners fail to gain sufficient confidence in their reading of ECGs. A British study of final year medical students showed that only 9% felt confident in their interpretation of ECG tracings.1 In that particular study, complete heart block, atrial fibrillation, and inferior myocardial were correctly recognized 67%, 54%, and 61% of the time, respectively–whereas ventricular fibrillation and tachycardia were correctly recognized 100% and 96% of the time, respectively.1 In efforts to investigate the best way to improve learner competence, Mahler et. al showed that self-directed learning was inferior to workshop or lecture-based formats in a population of medical students.2 These findings were extended to junior doctors in a British population (FY1) showing that a focused teaching program increased learner levels of confidence and competence more than a self-directed program.3 Unsurprisingly, the FY1 population in this study demonstrated higher levels of confidence and competence in ECG interpretation than undergraduate medical trainees.3
In America, there exists a similar lack of confidence in ECG interpretation amongst healthcare providers. This translates to reliance on computerized algorithms that are built into many modern ECG machines, however this reliance comes with associated risks. A retrospective study in 2004 showed that 382 (35%) out of 1085 patients had ECGs that were misinterpreted by the computer as having atrial fibrillation.4 In 92 (24%) of these patients, the ordering physician did not recognize the computer error and consequently anticoagulant and antiarrhythmic drugs were prescribed in 39 (10%) patients.4
Despite recognition of this pervasive problem, there has yet to be an optimal method of teaching ECG interpretation that has proven to be more effective than another.5 In a systematic review comparing the common methods of self-directed, workshop-based, lecture-based, and web-based, as well as other uncommon methods of learning, no single method was definitively shown to be superior.5 Rather, self-directed learning was again shown to be associated with lower interpretation competence.5 Additionally, this review showed that summative assessments were associated with improved interpretation competence relative to formative assessments.5
As theory of learning research has blossomed, the small-group format of didactic instruction has been shown to increase learner identification of knowledge gaps and correction of misconceptions, as well as increase satisfaction with learning.6 Small-group didactics also promote deep learning as opposed to surface learning–a feature that would be ideally suited towards the nuanced skill of ECG interpretation.6
Testing has been shown to enhance retention of semantic memory in a phenomenon known as the testing effect.7 The testing effect supports summative assessments as not just a means to gauge competence, but also as a tool for learning.7 In fact, testing was shown in a randomized controlled trial to be more effective in producing long term retention relative to study alone.8 As a related phenomenon, it has been determined that spaced/iterative learning practices (also known as expanded retrieval practice) improve comprehension and retention in the acquisition of multiple forms of knowledge.9,10 Spaced learning is based on the testing effect, as well as empirical evidence that demonstrate that the probability of memory retention is proportional to the length of time between initial learning and recall. This association has been shown to be valid until a limit, after which the initially learned knowledge may be lost.9,10
First year postgraduate residents (henceforth referred to as interns) are the least experienced of all graduate medical education learners in America, and likely have the lowest levels of confidence (analogous to their British counterparts).3 There are a number of existing barriers to education in the graduate medical education arena including lack of structured didactic time, physician burnout, and competing urgent clinical responsibilities to name a few. The recent COVID-19 pandemic further strained the already tenuous systems in place for effective graduate medical education by relegating conferences and courses to the virtual realm, or necessitating their cancellation altogether.
Senior resident physicians are frequently called upon as the primary source of medical education for interns and medical students while on clinical rotations.11 The reasons for this are myriad, but largely relate to the proximity of resident physicians to the material being taught, ability of residents to incorporate practical clinical relevance to abstract medical topics, the amount of time spent between resident and intern, as well as the proximity of roles (social and cognitive congruence) between teacher and student.12 Additionally, it has been shown that peer teaching is at least equivalent to expert teaching with regards to learner outcomes in medical education, however peer teaching maintains the added benefit of increasing the teacher’s confidence in teaching ability and grasp on the content itself.13 As such, a number of clinician–educator tracks are propagating amongst Internal Medicine residencies; however, as “resident as teacher” programs continue to grow, the optimal method of instruction has yet to be determined.12,14
Our purpose in this project was to determine if a spaced learning course in ECG interpretation could be feasibly implemented during a busy inpatient rotation, and to determine the effects of peer-led, small-group learning as applied to the instruction of ECGs in graduate medical education. Our study was designed and implemented entirely by a peer second-year resident with participation by interns.