Using a 360° Virtual Reality or 2D Video to Learn History Taking and Physical Examination Skills for Undergraduate Medical Students: Pilot Randomized Controlled Trial

BACKGROUND

Learning through a 360° virtual reality (VR) or 2D video represents an alternative way to learn a complex medical education task. However, there is currently no consensus on how best to assess the effects of different learning materials on cognitive load estimates, heart rate variability (HRV), outcomes, and experience in learning history taking and physical examination (H&P) skills.

OBJECTIVE

The aim of this study was to investigate how learning materials (ie, VR or 2D video) impact learning outcomes and experience through changes in cognitive load estimates and HRV for learning H&P skills.

METHODS

This pilot system-design study included 32 undergraduate medical students at an academic teaching hospital. The students were randomly assigned, with a 1:1 allocation, to a 360° VR video group or a 2D video group, matched by age, sex, and cognitive style. The contents of both videos were different with regard to visual angle and self-determination. Learning outcomes were evaluated using the Milestone reporting form. Subjective and objective cognitive loads were estimated using the Paas Cognitive Load Scale, the National Aeronautics and Space Administration Task Load Index, and secondary-task reaction time. Cardiac autonomic function was assessed using HRV measurements. Learning experience was assessed using the AttrakDiff2 questionnaire and qualitative feedback. Statistical significance was accepted at a two-sided P value of <.01.

RESULTS

All 32 participants received the intended intervention. The sample consisted of 20 (63%) males and 12 (38%) females, with a median age of 24 (IQR 23-25) years. The 360° VR video group seemed to have a higher Milestone level than the 2D video group (P=.04). The reaction time at the 10th minute in the 360° VR video group was significantly higher than that in the 2D video group (P<.001). Multiple logistic regression models of the overall cohort showed that the 360° VR video module was independently and positively associated with a reaction time at the 10th minute of ≥3.6 seconds (exp B=18.8, 95% CI 3.2-110.8; P=.001) and a Milestone level of ≥3 (exp B=15.0, 95% CI 2.3-99.6; P=.005). However, a reaction time at the 10th minute of ≥3.6 seconds was not related to a Milestone level of ≥3. A low-frequency to high-frequency ratio between the 5th and 10th minute of ≥1.43 seemed to be inversely associated with a hedonic stimulation score of ≥2.0 (exp B=0.14, 95% CI 0.03-0.68; P=.015) after adjusting for video module. The main qualitative feedback indicated that the 360° VR video module was fun but caused mild dizziness, whereas the 2D video module was easy to follow but tedious.

CONCLUSIONS

Our preliminary results showed that 360° VR video learning may be associated with a better Milestone level than 2D video learning, and that this did not seem to be related to cognitive load estimates or HRV indexes in the novice learners. Of note, an increase in sympathovagal balance may have been associated with a lower hedonic stimulation score, which may have met the learners' needs and prompted learning through the different video modules.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03501641; https://clinicaltrials.gov/ct2/show/NCT03501641.

Performance and onsite regeneration of natural zeolite for ammonium removal in a field-scale non-sewered sanitation system

Natural zeolite clinoptilolite was used as the primary ammonium removal method from the permeate of an anaerobic membrane bioreactor (AnMBR) treating high-strength blackwater generated from a community toilet facility. This zeolite-based nutrient capture system (NCS) was a sub-component of a non-sewered sanitation system (NSSS) called the NEWgenerator and was field tested for 1.5 years at an informal settlement in South Africa. The NCS was operated for three consecutive loading cycles, each lasting 291, 110, and 52 days, respectively. Both blackwater (from toilets) and blackwater with yellow water (from toilets and urinals) were treated during the field trial. Over the three cycles, the NCS was able to remove 80 ± 28%, 64 ± 23%, and 94 ± 11%, respectively, of the influent ammonium. The addition of yellow water caused the rapid exhaustion of zeolite and the observed decrease of ammonium removal during Cycle 2. After Cycles 1 and 2, onsite regeneration was performed to recover the sorption capacity of the spent zeolite. The regenerant was comprised of NaCl under alkaline conditions and was operated as a recycle-batch to reduce the generation of regenerant waste. Modifications to the second regeneration process, including an increase in regenerant contact time from 15 to 30 h, improved the zeolite regeneration efficiency from 76 ± 0.7% to 96 ± 1.0%. The mass of recoverable ammonium in the regenerant was 2.63 kg NH4-N and 3.15 kg NH4-N after Regeneration 1 and 2, respectively. However, the mass of ammonium in the regenerant accounted for only 52.8% and 54.4% of the estimated NH4-N originally sorbed onto the zeolite beds after Cycles 1 and 2, respectively. The use of zeolite clinoptilolite is a feasible method for ammonium removal by NSSS that observe variable nitrogen loading rates, but further research is still needed to recover the nitrogen from the regenerant waste.

Incidence of stroke on Kinmen, Taiwan

This study aims to assess the incidence, case-fatality rate and risk factors of stroke on Kinmen Island, Taiwan, from 1993 to 1996. A population-based stroke survey was carried out in 1993 and 1996 to collect data on all subjects in the population aged 50 years and older residing on Kinmen. There were 63 stroke events (53 first ever and 10 recurrent) identified in this period. The average annual incidence rate of first-ever stroke for people aged 50 years or older was 527 per 100,000 population (95% confidence interval, CI, 297-757). The 28-day case-fatality rate was 24.5% (95% CI 12.9-36. 1%) for first-ever stroke and 60% (95% CI 29.6-90.4%) for recurrent stroke. Multivariate analyses performed with the Cox proportional hazard model revealed the following risk factors to be independent predictors of stroke: hypertension, diabetes and alcohol use. The incidence and case- fatality rate of stroke on Kinmen is similar to that of several other countries. Hypertension is the most common risk factor in this population. Due to a relatively small number of outcome events, these findings require confirmation.

Subjective memory complaint in relation to cognitive performance and depression: a longitudinal study of a rural Chinese population

OBJECTIVES

To examine the associations of subjective memory complaint (SMC) in old age with (a) objective test performance, (b) past and subsequent cognitive decline, and (c) depression.

DESIGN

A group of community residents were examined twice during a 3-year period.

SETTING

Two townships on a rural Chinese islet.

PARTICIPANTS

A total of 543 men and women aged 65 years and older.

MEASUREMENTS

During each examination, neurologists interviewed and examined all participants for dementia and asked the question, "Do you have trouble with your memory?" In addition, research assistants administered (a) the Cognitive Abilities Screening Instrument (CASI) to assess cognitive abilities, including long-term memory (LTM) and short-term memory (STM), and (b) the Geriatric Depression Scale-Short Version (GDS-S) to assess symptoms of depression.

RESULTS

At each examination, almost half of the subjects acknowledged having trouble with their memory (the SMC+ group). At both examinations, the SMC+ group scored significantly lower on the CASI and significantly higher on the GDS-S than the SMC- group. However, the presence of SMC was not associated with faster cognitive decline over the past or subsequent 3 years. There were no consistent associations between SMC and the demographic variables of age, gender, and education at the two examinations. Logistic regression analysis showed that SMC was associated with poorer memory test scores after controlling for gender, age, education, and depression.

CONCLUSIONS

SMC was associated with poorer objective memory performance even after controlling the effect of depression and demographic data, but SMC did not predict faster cognitive decline or dementia over 3 years.

ApoE genotype in relation to AD and cholesterol: a study of 2,326 Chinese adults

OBJECTIVE

To calculate the frequencies of apolipoprotein E (apoE) alleles in a large Chinese community sample and to compare the serum cholesterol levels of epsilon2, epsilon3, and epsilon4 carriers.

BACKGROUND

In comparison with Western populations, a lower frequency of the apoE epsilon4 allele among the Chinese has been proposed as one factor for the lower prevalence of AD found in Chinese populations, but there are insufficient Chinese data on epsilon4 frequency that are based on large community samples. In addition, although Western studies have repeatedly found a lower cholesterol level in epsilon2 carriers and a higher cholesterol level in epsilon4 carriers in comparison with epsilon3 homozygotes, two Chinese studies have yielded inconsistent findings between them.

METHODS

During the incidence phase of an epidemiologic survey of several neurologic disorders in a Chinese community, the authors took blood samples from 2,326 participants to determine the apoE genotypes and to measure cholesterol levels.

RESULTS

The allelic frequencies of epsilon2, epsilon3, and epsilon4 were 11.8%, 76.4%, and 11.8% among 17 AD patients, and 7.8%, 84.1%, and 8.1% for the entire sample. The mean cholesterol level of the epsilon2 carriers was significantly lower, and that of the epsilon4 carriers significantly higher, than that of the epsilon3 homozygotes.

CONCLUSIONS

The obtained epsilon4 rate of 8.1% is lower than most of the Western findings, and this may account in part for the lower prevalence of AD found among the Chinese. The associations between the apoE genotype and serum cholesterol level are similar between Chinese and white populations.

Proton magnetic resonance spectroscopy in deep cerebral venous thrombosis

A 63-year-old man developed a severe left frontal headache followed by an acute change of mentality 6 days later. Magnetic resonance imaging revealed bilateral thalamic ischemia. Angiography confirmed the occlusion of deep cerebral veins. Proton magnetic resonance spectroscopy (1H-MRS) of the thalami showed normal N-acetylaspartate (NAA) peak and the presence of lactate peak, indicating a relatively preserved neuronal viability. The patient improved during the follow-up period, and returned to work 45 days after the onset of the disease. With 1H-MRS, prognosis following venous infarctions may be feasible.

Postnatal development and testosterone-dependence of GP-83 and GP-49, two sperm maturation-related glycoproteins in BALB/c mouse epididymis

The secretion of sperm maturation-related molecules by the epididymis is subjected to developmental and hormonal regulation. In the BALB/c mouse, we found that GP-83 and GP-49, two sperm maturation-related glycoproteins, were secreted by the epididymis. The present study investigated the postnatal development and testosterone-dependence of these two molecules. Histochemical localization in paraffin sections revealed that wheat-germ agglutinin (WGA)-binding sites were first present in the epididymis of 4-week-old mice. The distribution of WGA-binding sites was the same as that of more mature mice, i.e., it was first found in the principal cells of the corpus epididymidis, and gradually appeared in the contents of epididymal tubules. On WGA blots, GP-83 and GP-49 were identified in the corpus, and GP-83 was identified in the cauda of the epididymis. In mice that had received unilateral orchiectomy at 4 weeks of age, GP-83 and GP-49 were present in both intact and orchiectomized epididymides 4 weeks after the operation. In the epididymides of mice that had received bilateral orchiectomy, GP-83 and GP-49 were barely identifiable. However, the presence of these two molecules was restored if testosterone was supplemented immediately after orchiectomy. These results indicate that GP-83 and GP-49 are secreted de novo in the epididymis, and that the secretion of these two molecules is developmentally regulated and androgen-dependent.