Hybrid Simulation Experience-Hybrid Simulator Model vs. Manikin in Bladder Catheterization Procedure: A Pilot Study

Sara Nikolic1, Mirjam Mocnik2 and Sebastjan Bevc3,4* 1Clinic for Internal Medicine, Department of Gastroenterology, University Clinical Center Maribor, Slovenia 2Clinics for Pediatrics, University Clinical Center Maribor, Slovenia 3Clinics for Internal Medicine, Department of Nephrology, University Clinical Center Maribor, Slovenia 4Faculty of Medicine, University of Maribor, Slovenia *Corresponding author: Sebastjan Bevc, Associate Professor, Department of Nephrology, Clinic for Internal Medicine, University Clinical Center Maribor and Faculty of Medicine, University of Maribor, Taborska 8, 2000 Maribor, Slovenia, Tel: + 0038623212485; E-mail: sebastjan.bevc@ukc-mb.si


Introduction
Simulation based education is a branch of simulation technology which uses different approaches to simulate clinical situations with the purpose of active clinical skills learning. The theoretical basis for learning by simulation is the constructivist model of learning which states that learning is the result of active participation in the process of acquiring knowledge and not just passive reception of information. The constructivist learning model is characterized by better knowledge retention, faster transfer in the learning process and the flattening of the curve of forgetting [1]. Constructivist model compared to the traditional model is more effective in the field of learning with We used two types of simulation in our research -simulation of the human body part (manikins) and hybrid simulation model for the bladder catheterization procedure. The primary aim of our research was to investigate an influence of hybrid simulation on the students' success at bladder catheterization procedure, on the knowledge retention and communication with patient-actors. Additionally, we were interested in students' perception of usefulness of hybrid simulation and their general satisfaction with it.

Subjects
The research project involved students attending 6th year of the Faculty of Medicine, University of Maribor, a total of 28 students sampled by opportunity sampling in academic year 2013/2014. They were randomly divided into two groups: hybrid simulator model (HSM) group (N=14) and control group (N=14). HSM consisted of human body part simulation model being between the legs of simulated patient (Figure 1). Control group performed on body part model (manikins) (Figure 2). After oral agreement, the informed consent form was signed by the participants. Ethical committee permission was not obligatory.

Data collecting
Students attended a clinical skills workshop as part of the Internal Medicine practicum, where they were taught the bladder catheterization (BC) procedure. Workshop was held once in the winter and once in the summer semester. An objective structured clinical examination (OSCE) 1 followed six weeks after the workshop. At OSCE 1 students performed the BC procedure twice, on a male and female manikins ( Figure 1; Table 1) or HSM depending on whether they we part of a control or HSM group. Six weeks after, the OSCE 1 was followed by OSCE 2, in which students were performing BC procedure, on the same simulation modality as in OSCE 1. BC procedure checklist for male model had the maximum of 32 points, and the female 31. In both cases there was a time limit of 10 minutes to perform the catheterization. No points were assigned after the time limit.

Data processing
Statistical analysis was performed with SPSS Statistics 19. As part of the descriptive statistical analysis we determined following parameters: minimum and maximum result, the average and standard deviation of points scored and the time needed for the completion of the procedure. All these values were calculated for all students together and for each group separately. Also, we performed a comparison of averages between the two groups with respect to the time required for BC procedure and the result achieved in the OSCE with the test of independent samples. Statistical significance was set at p-value <0.05. We also analyzed the responses of the questionnaire. Finally, we counted the most common mistakes for OSCE 1 and 2 on male and female model and compare the dynamics of the frequency of errors in the manikin model and HSM. Table 1 presents descriptive statistics (minimum, maximum, mean and standard deviation) for the control and research group as well as the comparison of OSCE 1 and 2 outcomes (score and time). There was a statistically significant improvement in OSCE score in male and female model (manikin and HSM) in the OSCE 2, while the difference in the time required for the BC procedure was not statistically significant.

Results
Research group scored higher mean scores in both OSCE 1 and OSCE 2 ( Figure 3). However, despite higher mean score, no statistically significant difference between control and research group neither in OSCE 1 nor in OSCE 2 was found (Table 2).
Finally, perception of usefulness in different types of simulation on a Linkert scale from 1-5 (1 -not useful at all, 5 -very useful) is showed in Figure 4. We found a statistically significant difference between control and research group (p=0.022).

Discussion
The primary goal of medical school is to provide the future doctors with competencies, which will suffice for high-quality patient treatment. The general purpose of research in the field of medical education is to search for most efficient and economic ways of education. Improved outcomes in treatment of patients directly rely on the mode of education [12]. Our study sought to identify the effectiveness of teaching BC procedure by hybrid simulation. The effectiveness was measured by success at OSCE, retention of knowledge, number of communication errors with patient-actors during OSCE and the self-evaluation of the usefulness of hybrid simulation.
In the control and the research group there was a statistically significant improvement in OSCE score, while significant differences in the time required for the completion of BC procedure were not found. Students of both study groups 6 weeks after OSCE 1, equipped with the feedback and their assessors, inserted bladder catheter better at OSCE 2 and took enough time to do so. Performance results OSCE 2 coincided with the results of the Dutch study in 2011, which showed that deliberate practice on simulators has positive effects on learning clinical skills [13].
Despite the fact that research group was more successful at both OSCEs, the difference in the mean OSCE score was not statistically significant. Sample size of our study was small and probably more participants would generate statistical significance. It was suggested that the presence of the patient-actor improves communication steps in the protocol, however, it can also reduce the technical skills and concentration of the student, thus research group students would not score significantly better. In fact, that explanation is supported by study of Posner et al., who simulated gynecological examination in hybrid simulation using different friendly and talkative patients-actors. They found that friendly and very talkative patients-actors reduced the technical skill and concentration of the students [12].
Students made most errors at the level of communication.
Communication points represent about a quarter of our protocol. Improving outcomes of OSCEs were associated with improvement in communication with the patient-actor. Our analysis showed that students put more emphasis on sterility areas when they see a patientactor in front of them. Error in the handling of the foreskin was the only one who appeared frequently in both OSCEs and we associated it with the feature of our model (penis without retractable foreskin).
The purpose of the advanced simulations is to raise the efficiency in acquiring and retention of knowledge for the sake of future clinical practice. Study by Lo et al. from 2011 found that high-fidelity simulation in learning advanced cardiac life support is more effective, but the retention of knowledge after one year was the same as with traditional learning [14]. We did not test knowledge retention after one year, because this was not possible due to the study schedule of 6th year medical school students. However, examinations were conducted after 6 and 12 weeks (OSCE 1 and 2) and we found that the students performed better after 12 than 6 weeks. This could be interpreted by the fact that short time had passed between the examinations and the BC procedure was not forgotten. For the future investigations, it would be useful to determine if the hybrid simulation allows better retention of knowledge even after one year.
A very important factor in learning is general satisfaction with the way students learn. Research group students have evaluated learning with simulation as more useful compared to students in the control group. The difference was statistically significant. Our findings are supported by the conclusions of the study by Raymond et al. from 2009 focused on comparing the simulation to the group discussion when teaching emergency medicine. They associated better learning outcomes with the popularity of simulation among students [15].
The small sample of volunteers participating is a main weakness of our study. Between the two OSCEs some students dropped out. Another disadvantage of our study is predominant quantitative assessment of both technical and communication skills. On the other hand patients -actors could have assessed the students by patient perception score (PPS). Nowadays, cutting edge technology enables puppets to "speak", but a large survey of physicians and midwives (Fire drill Simulation and Evaluation (Safe)) did not confirm the advantages of learning with advanced technology and high-fidelity simulation over the hybrid simulation. Therefore, more accurate assessment could replace learning with complex simulators [16].
The advantage of our research is a good bias, because the students were assessed by OSCE, the assessment was carried out by experienced peer tutors and patients-actors were precisely instructed how to behave. Via a questionnaire, we summarized the students' opinion about the BC procedure simulation. If peer tutors assess using a checklist, they are equivalent to experienced clinicians; therefore peertutor assessment was not questionable [17]. However, we would tend to educate the patient-actors in future studies, because research has shown a significant influence of the patient-actors training on the performance of a clinical skill [18].
The goal of our research project was to determine how hybrid simulation influences the learning process of BC procedure.
The results of our study has shown that students preformed BC procedure statistically better the second time, whatever the simulation surroundings. Research group had slightly better results, but no statistically significant differences were found. Fewer communication errors were found in the research group only during OSCE 1. Students felt that learning by simulation is very useful, especially the hybrid simulation.
The hybrid simulation allows a better simulation scenario for medical students during BC procedure learning, which is a demanding clinical skill where communication with patients is often neglected. Our results encourage further research of hybrid simulation and its impact on the technical and communication skills as well its consequences on long-term retention of knowledge.