Worldwide, cardiovascular disease is estimated to be the leading cause of death in the world 2020 [1]. Electrocardiography (ECG) continues to be the most commonly used laboratory procedure for the diagnosis of heart disease. Introduced in 1902 by Einthoven [2], the procedure reflects electrical changes associated with primary or secondary myocardial processes for example coronary artery disease, hypertension, and electrolyte abnormalities [3].

Physicians in most clinical specialities, including general practice are expected to have a sufficient knowledge about ECG interpretation to be able to make accurate diagnoses, decide on patient management or further referrals. An adequate knowledge base should include the ability to define, recognize, and understand the basic pathophysiology of certain electrocardiographic abnormalities [3]. Our experience, together with existing research, suggests that most medical students do not feel competent in their interpretation of ECG [4]. In the extension this could negatively influence patient management decisions and could threaten patient safety [5, 6].

Despite the importance of ECG-training, clinical tutors seem to have increasing difficulties in meeting the need for more training in ECG interpretation due to shortage of time or other reasons. Thus, alternative and flexible ways to learn and practice ECG interpretation are needed [7].

Education offered via the Internet is usually readily available, geographically independent and flexible [8]. If designed in a proper way with a good pedagogical method, such as active learning, simulation and with a case-based approach, interactive learning systems may improve the quality of education, facilitate visualisation and understanding and also increase the effectiveness of the education [9–12].

The aim of this project was to evaluate a web-based comprehensive ECG interpretation programme for medical students at Karolinska Institutet during the internal medicine course. We assessed the attitude of the students towards web-based ECG learning in general and the usefulness of a specific programme. We also intended to objectively assess the impact and effectiveness of web-based ECG tutorials by comparing the learning outcomes in the intervention and the control group with a diagnostic test.

20 of the 32 students in the test group course volunteered to use the ECG-system. In the control group, 30 students fulfilled the course without having access to the ECG program.

At the individual semi-structured interview the 20 students in the test group who had used the programme were asked to rank their apprehension of the system based on a five-graded scale (1- bad to 5 – very good). In average, they ranked the utility of the web-based programme for this purpose as 4.1 (SD 1.0) and the quality of the programme software as 3.9 (SD 0.3).

The diagnostic test consisted of interpretation/reading of 8 different ECG:s. These ECG:s had previously been used in the examination by the same two groups of students during their 5th semester At the optional diagnostic test by the end of the sixth semester, 17/20 students in the test group, and 25/30 in the control group completed the voluntary test. The test group scored significantly better (average 9.7 (SD 2.19)) as compared with 8.1 (SD 2.47) for the control group, (p = 0.03). Maximum points were 16. The individual scores at the test are depicted in Figure 4.

The importance of a basic understanding of ECG interpretation is of critical importance for physicians but despite this gaps in knowledge exist. For example, in a recent experimental study, it was shown that the performance of internal medicine and emergency medicine residents in ECG-interpretation was rather low [17]. The competency in ECG-interpretation improves with training [18], but training seems to be deficient at many universities. Thus, it is important to find better ways for medical students to begin and maintain this training.

The students indicated a positive attitude to web-based ECG-learning in general and the utility of the specific programme and the web-based ECG interpretation programme used in this study seemed to increase skills in ECG-interpretation when evaluated by the diagnostic test. Our results thus suggest benefits with added web-based ECG-learning programme over only conventional teaching of ECG. However a limitation with this study is that some of the students did not perform the voluntary diagnostic test and that a pre-test was not performed. There is also a possibility of a volunteer bias in these kind of studies, a fact that is always existing when there are few opportunities to make the test compulsory before a new educational tool is tested. Additional studies are thus needed to assess the possible advantages with web-based ECG-learning and if it can replace conventional learning. To investigate learning outcomes in more detail and also to assess if these outcomes are related to background factors such as time spent in the programme and individual learning techniques we are projecting further studies.

Web-based education is a branch of Electronic learning (E-learning) that is increasingly used for medical education. The major reason for this seems to be the general advantages of Internet like availability, geographic independence, flexibility, improved visualization and the opportunity of interaction. Hudson [9] points out the fact that most studies in medical E-learning compare traditional education with e-learning without evaluation of the "if, what and why" of possible pedagogical benefits of E-learning. In our case, students reported some specific benefits of the ECG tool like the possibility to use it individually and at any time.

Even though the pedagogical and technical solutions used in this system seems to be of value to improve learning outcomes, a more thorough evaluation is needed to find solutions applicable for Web-based education in general.

For example, we showed 32 students at one single occasion how to use the web-based ECG interpretation programme in the beginning of the period. 62% of the students voluntarily used the programme. In our opinion this is a fairly good proportion of students using the system and others have had similar numbers of student participation introducing e-learning [19].

In this study we did not investigate why some students used the programme and others did not. In some cases the reason might be due to lack of computers, or a behavioural resistance [20] to a relatively new way of studying. indicating the opposite. It may be argued that the better result in our intervention group may be due to a positive selection of students but Hahne et al did not show that students who participate or agree to use e-learning are better students than those who do not use e-learning [19]. Further scrutinizing of the students readiness to use or not use new educational instruments is important in faculty development.

Optimal methods to learn and maintain ECG interpretation skills and competence are not yet fully understood [21, 22]. The different kinds of ECG:s that a physician in general practice needs to recognize is well known, but the number of ECG-examples needed to be interpreted to learn and maintain ECG competence is still a question. In the Clinical Competence Statement on Electrocardiography from the American College of Cardiology and the American Heart Association [3] a total number of 500 ECG:s is demanded to learn ECG-interpretation and a 100 ECG:s yearly to maintain ECG interpretation skills. These indicated numbers are based more on opinion than statistical surveys.

In conclusion, the described ECG training system seems to have a good potential to facilitate ECG learning both in individual self-learning and to improve the effectiveness of teacher-controlled tuition. Due to the lack of pre-intervention testing and possible volunteer bias in our study more research need to be performed to fully understand the "if's, where's and how's" of using computer based ECG training. However this interactive ECG interpretation system together with a learning management system might be a suitable model to be used to further study this subject.