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In this study, the pull-in phenomenon of a Nano-actuator is investigated employing a nonlocal Bernoulli-Euler beam model with clamped-clamped conditions. The model accounts for viscous damping, residual stresses, the van der Waals (vdW) force and electrostatic forces with nonlocal effects. The hybrid differential transformation/finite difference method (HDTFDM) is used to analyze the nonlocal effects on a graphene sheet nanobeam, which is electrostatically actuated under the influence of the coupling effect, the von Kármán nonlinear strains and the fringing field effect. The pull-in voltage as calculated by the presented model deviates by no more than 0.29% from previous literature, verifying the validity of the HDTFDM. Furthermore, the nonlocal nonlinear behavior of the electrostatically actuated nanobeam is investigated, and the effects of viscous damping, residual stresses, and length-gap ratio are examined in detail. Overall, the results reveal that small scale effects significantly influence the characteristics of the graphene sheet nanobeam actuator.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Introduction: Although acute gastroenteritis is an extremely common childhood illness, there is a paucity of literature characterizing the associated pain and its management. Our primary objective was to quantify the pain experienced by children with acute gastroenteritis in the 24-hours prior to emergency department (ED) presentation. Secondary objectives included describing maximum pain, analgesic use, discharge recommendations, and factors that influenced analgesic use in the ED. Methods: Study participants were recruited into this prospective cohort study by the Alberta Provincial Pediatric EnTeric Infection TEam between January 2014 and September 2017. This study was conducted at two Canadian pediatric EDs; the Alberta Children's Hospital (Calgary) and the Stollery Children's Hospital (Edmonton). Eligibility criteria included < 18 years of age, acute gastroenteritis (□ 3 episodes of diarrhea or vomiting in the previous 24 hours), and symptom duration □ 7 days. The primary study outcome, caregiver-reported maximum pain in the 24-hours prior to presentation, was assessed using the 11-point Verbal Numerical Rating Scale. Results: We recruited 2136 patients, median age 20.8 months (IQR 10.4, 47.4); 45.8% (979/2136) female. In the 24-hours prior to enrolment, 28.6% (610/2136) of caregivers reported that their child experienced moderate (4-6) and 46.2% (986/2136) severe (7-10) pain in the preceding 24-hours. During the emergency visit, 31.1% (664/2136) described pain as moderate and 26.7% (571/2136) as severe. In the ED, analgesia was provided to 21.2% (452/2131) of children. The most commonly administered analgesics in the ED were ibuprofen (68.1%, 308/452) and acetaminophen (43.4%, 196/452); at home, acetaminophen was most commonly administered (77.7%, 700/901), followed by ibuprofen (37.5%, 338/901). Factors associated with analgesia use in the ED were greater pain scores during the visit, having a primary-care physician, shorter illness duration, fewer diarrheal episodes, presence of fever and hospitalization. Conclusion: Although children presenting to the ED with acute gastroenteritis experience moderate to severe pain, both prior to and during their emergency visit, analgesic use is limited. Future research should focus on appropriate pain management through the development of effective and safe pain treatment plans.
Our pilot study evaluated the feasibility, effectiveness, and implementation of a group-based lifestyle-integrated functional exercise (Mi-LiFE) program for older adults in an interprofessional primary care practice. A physical therapist taught participants how to integrate strength and balance activities into daily routines during one individual and four group sessions, and two follow-up phone calls. Feasibility outcomes were recruitment, adherence, and retention over 6 months. Physical activity (PA) (accelerometer, International Physical Activity Questionnaire [IPAQ]), Short Physical Performance Battery (SPPB), and health-related quality of life (EuroQol Five-Dimensional Questionnaire with 3 Levels [EQ5D-3L]) were evaluated at baseline and 6 months. Of the 123 eligible individuals, 39 per cent participated and 61 per cent were not interested or unreachable. Forty-eight participants (mean ± standard deviation [SD] age = 81 ± 5 years; body mass index [BMI] = 28 ± 5 kg/m2; 60% women; moderate-to-vigorous PA = 49 ± 87 minutes/week) enrolled. Four participants withdrew prior to intervention. Thirty-two participants (67%) were retained at follow-up. Daily diary-documented adherence was 50 per cent at 6 months, and 77 per cent attended more than four sessions. No statistically significant changes in moderate-to-vigorous PA and SPPB outcomes were observed; yet self-reported strength and balance PA and quality of life significantly improved at follow-up. The Mi-LiFE program is feasible with acceptable recruitment and attendance rates alongside modifications to address retention and adherence challenges. These findings inform the feasibility of future pragmatic exercise programs in primary care for older adults.
We assessed self-reported drives for alcohol use and their impact on clinical features of alcohol use disorder (AUD) patients. Our prediction was that, in contrast to “affectively” (reward or fear) driven drinking, “habitual” drinking would be associated with worse clinical features in relation to alcohol use and higher occurrence of associated psychiatric symptoms.
Fifty-eight Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) alcohol abuse patients were assessed with a comprehensive battery of reward- and fear-based behavioral tendencies. An 18-item self-report instrument (the Habit, Reward and Fear Scale; HRFS) was employed to quantify affective (fear or reward) and non-affective (habitual) motivations for alcohol use. To characterize clinical and demographic measures associated with habit, reward, and fear, we conducted a partial least squares analysis.
Habitual alcohol use was significantly associated with the severity of alcohol dependence reflected across a range of domains and with lower number of detoxifications across multiple settings. In contrast, reward-driven alcohol use was associated with a single domain of alcohol dependence, reward-related behavioral tendencies, and lower number of detoxifications.
These results seem to be consistent with a shift from goal-directed to habit-driven alcohol use with severity and progression of addiction, complementing preclinical work and informing biological models of addiction. Both reward-related and habit-driven alcohol use were associated with lower number of detoxifications, perhaps stemming from more benign course for the reward-related and lack of treatment engagement for the habit-related alcohol abuse group. Future work should further explore the role of habit in this and other addictive disorders, and in obsessive-compulsive related disorders.
OBJECTIVES/SPECIFIC AIMS: As the issues facing our global society become more complex, university faculty are called upon to address these contemporary problems using interdisciplinary approaches. But do reappointment, promotion, and tenure (RPT) guidelines reflect and reward this fundamental change in the nature of higher education and scholarly inquiry? After collecting all of the RPT guidelines across the university, our research team at the University of Cincinnati (UC) conducted a content analysis of these documents to determine how collaborative work is defined, interpreted, and supported. In addition, we also sought to identify differences in how collaborative work is valued across disciplines and how that value has changed over time. METHODS/STUDY POPULATION: An initial database was assembled that included two distinct data samples: historical and current. Both included RPT criteria for over 100 disciplinary units at the university. Working with the initial comprehensive database, the team narrowed content by selecting all language related to collaborative work using several relevant keywords or keyword fragments (team, collaborat[*], disciplin[*], and interprofessional). This process resulted in a subset of data reflecting the area of interest that could then be coded. Three investigators independently coded common portions of the data for categories. The investigators met regularly to compare the results of their coding, and discrepancies between the investigators’ coding schemes were resolved through discussion. The final, common coding scheme will used to code the remainder of the data by each independent investigator. The team meets weekly to discuss significant passages and assign codes, and then reach consensus related to important themes that are identified. Specifically, we will examine the frequency with which collaborative activities are included, the value and emphasis given to them, and the differences across units. Having a historical sample and a current sample also allows us to analyze trends over time and further compare disciplinary differences. RESULTS/ANTICIPATED RESULTS: UC is a diverse institution that includes world-renowned creative schools (the College Conservatory of Music and the College of Design, Architecture, Art, and Planning), as well as traditional colleges of medicine, nursing, pharmacy, allied health, engineering, business, arts and sciences, etc. UC also includes two branch campuses that specialize in associate’s degree level education. Given the diversity in educational and research missions across these areas, we anticipate discovering several themes within the RPT guidelines, primarily centered around the traditional foundations of faculty work such as service, research, and teaching. We anticipate strong differences by college and disciplinary focus, with emphasis on collaborative work and engagement increasing as RPT guidelines become more current. DISCUSSION/SIGNIFICANCE OF IMPACT: Our experience is that faculty members want to engage in collaborative work when possible and appropriate, but their perception is that independent contributions to their field are more highly valued than interdisciplinary work. As universities rush to endorse and promote interdisciplinary, team-oriented research and teaching, this study will afford a better understanding of the types of activities valued at one large and diverse urban institution, grounded in the actual language of RPT criteria.
The Pain Catastrophizing Scale (PCS) measures three aspects of catastrophic cognitions about pain—rumination, magnification, and helplessness. To facilitate assessment and clinical application, we aimed to (a) develop a short version on the basis of its factorial structure and the items’ correlations with key pain-related outcomes, and (b) identify the threshold on the short form indicative of risk for depression.
Social centers for older people.
664 Chinese older adults with chronic pain.
Besides the PCS, pain intensity, pain disability, and depressive symptoms were assessed.
For the full scale, confirmatory factor analysis showed that the hypothesized 3-factor model fit the data moderately well. On the basis of the factor loadings, two items were selected from each of the three dimensions. An additional item significantly associated with pain disability and depressive symptoms, over and above these six items, was identified through regression analyses. A short-PCS composed of seven items was formed, which correlated at r=0.97 with the full scale. Subsequently, receiver operating characteristic (ROC) curves were plotted against clinically significant depressive symptoms, defined as a score of ≥12 on a 10-item version of the Center for Epidemiologic Studies-Depression Scale. This analysis showed a score of ≥7 to be the optimal cutoff for the short-PCS, with sensitivity = 81.6% and specificity = 78.3% when predicting clinically significant depressive symptoms.
The short-PCS may be used in lieu of the full scale and as a brief screen to identify individuals with serious catastrophizing.
This study evaluated tumour necrosis factor-α, interleukins 10 and 12, and interferon-γ levels, peripheral blood mononuclear cells, and clusters of differentiation 17c and 86 expression in unilateral sudden sensorineural hearing loss.
Twenty-four patients with unilateral sudden sensorineural hearing loss, and 24 individuals with normal hearing and no history of sudden sensorineural hearing loss (who were attending the clinic for other problems), were enrolled. Peripheral blood mononuclear cells, and clusters of differentiation 11c and 86 were isolated and analysed. Plasma and supernatant levels of tumour necrosis factor-α, interferon-γ, and interleukins 10 and 12 were measured.
There were no significant differences with respect to age and gender. Monocyte population, mean tumour necrosis factor-α level and cluster of differentiation 86 expression were significantly increased in the study group compared to the control group. However, interferon-γ and interleukin 12 levels were significantly decreased. The difference in mean interleukin 10 level was not significant.
Increases in tumour necrosis factor-α level and monocyte population might play critical roles in sudden sensorineural hearing loss. This warrants detailed investigation and further studies on the role of dendritic cells in sudden sensorineural hearing loss.
Findings as to whether individuals’ experiences of physical maltreatment from their parents in childhood predict their own perpetration of physical maltreatment toward their children in adulthood are mixed. Whether the maltreatment experienced is severe versus moderate or mild may relate to the strength of intergenerational associations. Furthermore, understanding of the roles of possible mediators (intervening mechanisms linking these behaviors) and moderators of the intervening mechanisms (factors associated with stronger or weaker mediated associations) is still relatively limited. These issues were examined in the present study. Mediating mechanisms based on a social learning model included antisocial behavior as assessed by criminal behaviors and substance use (alcohol and drug use), and the extent to which parental angry temperament moderated any indirect effects of antisocial behavior was also examined. To address these issues, data were used from Generations 2 and 3 of a prospective three-generational study, which is an extension of the Oregon Youth Study. Findings indicated modest intergenerational associations for severe physical maltreatment. There was a significant association of maltreatment history, particularly severe maltreatment with mothers’ and fathers’ delinquency. However, neither delinquency nor substance use showed significant mediational effects, and parental anger as a moderator of mediation did not reach significance.
Evidence from animal models indicates that exposure to an obesogenic or hyperglycemic intrauterine environment adversely impacts offspring kidney development and renal function. However, evidence from human studies has not been evaluated systematically. Therefore, the aim of this systematic review was to synthesize current research in humans that has examined the relationship between gestational obesity and/or diabetes and offspring kidney structure and function. Systematic electronic database searches were conducted of five relevant databases (CINAHL, Cochrane, EMBASE, MEDLINE and Scopus). Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were followed, and articles screened by two independent reviewers generated nine eligible papers for inclusion. Six studies were assessed as being of ‘neutral’ quality, two of ‘negative’ and one ‘positive’ quality. Observational studies suggest that offspring exposed to a hyperglycemic intrauterine environment are more likely to display markers of renal dysfunction and are at higher risk of end-stage renal disease. There was limited and inconsistent evidence for a link between exposure to an obesogenic intrauterine environment and offspring renal outcomes. Offspring renal outcome measures across studies were diverse, with a large variation in offspring age at follow-up, limiting comparability across studies. The collective current body of evidence suggests that intrauterine exposure to maternal obesity and/or diabetes adversely impacts renal programming in offspring, with an increased risk of kidney disease in adulthood. Further high-quality, longitudinal, prospective cohort studies that measure indicators of offspring renal development and function, including fetal kidney volume and albuminuria, at standardized follow-up time points, are warranted.
Chlamydia trachomatis (CT) infections remain highly prevalent. CT reinfection occurs frequently within months after treatment, likely contributing to sustaining the high CT infection prevalence. Sparse studies have suggested CT reinfection is associated with a lower organism load, but it is unclear whether CT load at the time of treatment influences CT reinfection risk. In this study, women presenting for treatment of a positive CT screening test were enrolled, treated and returned for 3- and 6-month follow-up visits. CT organism loads were quantified at each visit. We evaluated for an association of CT bacterial load at initial infection with reinfection risk and investigated factors influencing the CT load at baseline and follow-up in those with CT reinfection. We found no association of initial CT load with reinfection risk. We found a significant decrease in the median log10 CT load from baseline to follow-up in those with reinfection (5.6 CT/ml vs. 4.5 CT/ml; P = 0.015). Upon stratification of reinfected subjects based upon presence or absence of a history of CT infections prior to their infection at the baseline visit, we found a significant decline in the CT load from baseline to follow-up (5.7 CT/ml vs. 4.3 CT/ml; P = 0.021) exclusively in patients with a history of CT infections prior to our study. Our findings suggest repeated CT infections may lead to possible development of partial immunity against CT.
Identifying factors that influence the functional outcome is an important goal in schizophrenia research. The 22q11.2 deletion syndrome (22q11DS) is a unique genetic model with high risk (20–25%) for schizophrenia. This study aimed to identify potentially targetable domains of neurocognitive functioning associated with functional outcome in adults with 22q11DS.
We used comprehensive neurocognitive test data available for 99 adults with 22q11DS (n = 43 with schizophrenia) and principal component analysis to derive four domains of neurocognition (Verbal Memory, Visual and Logical Memory, Motor Performance, and Executive Performance). We then investigated the association of these neurocognitive domains with adaptive functioning using Vineland Adaptive Behavior Scales data and a linear regression model that accounted for the effects of schizophrenia status and overall intellectual level.
The regression model explained 46.8% of the variance in functional outcome (p < 0.0001). Executive Performance was significantly associated with functional outcome (p = 0.048). Age and schizophrenia were also significant factors. The effects of Executive Performance on functioning did not significantly differ between those with and without psychotic illness.
The findings provide the impetus for further studies to examine the potential of directed (early) interventions targeting Executive Performance to improve long-term adaptive functional outcome in individuals with, or at high risk for, schizophrenia. Moreover, the neurocognitive test profiles may benefit caregivers and clinicians by providing insight into the relative strengths and weaknesses of individuals with 22q11DS, with and without psychotic illness.
Intermediate wheatgrass (Thinopyrum intermedium; IWG) is a perennial cereal crop undergoing development for grain production; however, grain yield declines of >75% are often observed after year 2 of the perennial stand and may be linked to soil nutrient depletion. Intercropping IWG with a perennial legume such as alfalfa (Medicago sativa) could benefit nutrient cycling while increasing agroecological diversity. Intermediate wheatgrass was established at five environmentally diverse sites in Minnesota, USA in (1) bi-culture with alfalfa, (2) non-fertilized monoculture and (3) monoculture fertilized annually in the spring with 80 kg N/ha. At northern sites where alfalfa growth was favoured, IWG grain yields were reduced in year 2 by growing IWG in bi-culture with alfalfa, relative to the monoculture systems. Across all sites IWG grain yield decreased by 90% in the non-fertilized monoculture, 80% in the fertilized monoculture and 65% in the bi-culture from year 2 to 4 and plant macronutrient concentrations decreased by 25–70%. In year 4, IWG grain yield was similar or greater in the bi-culture than the fertilized monoculture at three of the five sites and alfalfa biomass was correlated positively with grain yield, harvest index and nutrient uptake in the year 4 bi-culture. Chemical-nitrogen fertilization increased grain yields in year 2 but did not mitigate the decline in yields as stands aged. Intermediate wheatgrass in the bi-culture had similar yields and nutrient uptake and lower yield declines than the chemically fertilized stand at sites where alfalfa growth was maintained throughout the life of the stand.
BACKGROUND: Meningiomas are the most common primary benign brain tumors in adults. Given the extended life expectancy of most meningiomas, consideration of quality of life (QOL) is important when selecting the optimal management strategy. There is currently a dearth of meningioma-specific QOL tools in the literature. OBJECTIVE: In this systematic review, we analyze the prevailing themes and propose toward building a meningioma-specific QOL assessment tool. METHODS: A systematic search was conducted, and only original studies based on adult patients were considered. QOL tools used in the various studies were analyzed for identification of prevailing themes in the qualitative analysis. The quality of the studies was also assessed. RESULTS: Sixteen articles met all inclusion criteria. Fifteen different QOL assessment tools assessed social and physical functioning, psychological, and emotional well-being. Patient perceptions and support networks had a major impact on QOL scores. Surgery negatively affected social functioning in younger patients, while radiation therapy had a variable impact. Any intervention appeared to have a greater negative impact on physical functioning compared to observation. CONCLUSION: Younger patients with meningiomas appear to be more vulnerable within social and physical functioning domains. All of these findings must be interpreted with great caution due to great clinical heterogeneity, limited generalizability, and risk of bias. For meningioma patients, the ideal QOL questionnaire would present outcomes that can be easily measured, presented, and compared across studies. Existing scales can be the foundation upon which a comprehensive, standard, and simple meningioma-specific survey can be prospectively developed and validated.
Background: A will, power of attorney and advanced healthcare directive are critical to guide decision-making in people with cognitive decline. We identified characteristics that are associated with the existence of these documents in patients who presented to a rural and remote memory clinic (RRMC). Methods: 95 consecutive patients were included in this study. Patients and caregivers completed questionnaires on initial presentation to the RRMC and patients were asked if they have legal documents. Patients also completed neuropsychological testing. Statistical analysis (t-test and χ2 test) was performed to identify significant variables. Results: 70 patients had a will, 62 had a power of attorney and 21 had an advanced healthcare directive. Having a will was associated with good quality of life (p=0.001), living alone (p=0.034), poor verbal fluency (p=0.055) and European ethnicity (p=0.028). Factors associated with having a power of attorney included good quality of life (p=0.031), living alone (p=0.053) and poor verbal fluency (p=0.015). Old age (p=0.015), poor verbal fluency (p=0.023) and severity of cognitive and functional impairment (p=0.023) were associated with having an advanced healthcare directive. Conclusions: Our results indicate that poor quality of life, good verbal fluency, non-European ethnicity and living with others are associated with a lower likelihood of creating legal documents in patients with cognitive decline
Childhood obesity rates are higher among Indigenous compared with non-Indigenous Australian children. It has been hypothesized that early-life influences beginning with the intrauterine environment predict the development of obesity in the offspring. The aim of this paper was to assess, in 227 mother–child dyads from the Gomeroi gaaynggal cohort, associations between prematurity, Gestation Related-Optimal Weight (GROW) centiles, maternal adiposity (percentage body fat, visceral fat area), maternal non-fasting plasma glucose levels (measured at mean gestational age of 23.1 weeks) and offspring BMI and adiposity (abdominal circumference, subscapular skinfold thickness) in early childhood (mean age 23.4 months). Maternal non-fasting plasma glucose concentrations were positively associated with infant birth weight (P=0.005) and GROW customized birth weight centiles (P=0.008). There was a significant association between maternal percentage body fat (P=0.02) and visceral fat area (P=0.00) with infant body weight in early childhood. Body mass index (BMI) in early childhood was significantly higher in offspring born preterm compared with those born at term (P=0.03). GROW customized birth weight centiles was significantly associated with body weight (P=0.01), BMI (P=0.007) and abdominal circumference (P=0.039) at early childhood. Our findings suggest that being born preterm, large for gestational age or exposed to an obesogenic intrauterine environment and higher maternal non-fasting plasma glucose concentrations are associated with increased obesity risk in early childhood. Future strategies should aim to reduce the prevalence of overweight/obesity in women of child-bearing age and emphasize the importance of optimal glycemia during pregnancy, particularly in Indigenous women.
Giardia duodenalis is the most common intestinal parasite of humans in the USA, but the risk factors for sporadic (non-outbreak) giardiasis are not well described. The Centers for Disease Control and Prevention and the Colorado and Minnesota public health departments conducted a case-control study to assess risk factors for sporadic giardiasis in the USA. Cases (N = 199) were patients with non-outbreak-associated laboratory-confirmed Giardia infection in Colorado and Minnesota, and controls (N = 381) were matched by age and site. Identified risk factors included international travel (aOR = 13.9; 95% CI 4.9–39.8), drinking water from a river, lake, stream, or spring (aOR = 6.5; 95% CI 2.0–20.6), swimming in a natural body of water (aOR = 3.3; 95% CI 1.5–7.0), male–male sexual behaviour (aOR = 45.7; 95% CI 5.8–362.0), having contact with children in diapers (aOR = 1.6; 95% CI 1.01–2.6), taking antibiotics (aOR = 2.5; 95% CI 1.2–5.0) and having a chronic gastrointestinal condition (aOR = 1.8; 95% CI 1.1–3.0). Eating raw produce was inversely associated with infection (aOR = 0.2; 95% CI 0.1–0.7). Our results highlight the diversity of risk factors for sporadic giardiasis and the importance of non-international-travel-associated risk factors, particularly those involving person-to-person transmission. Prevention measures should focus on reducing risks associated with diaper handling, sexual contact, swimming in untreated water, and drinking untreated water.
Introduction: Survival from cardiac arrest has been linked to the quality of resuscitation care. Unfortunately, healthcare providers frequently underperform in these critical scenarios, with a well-documented deterioration in skills weeks to months following advanced life support courses. Improving initial training and preventing decay in knowledge and skills are a priority in resuscitation education. The spacing effect has repeatedly been shown to have an impact on learning and retention. Despite its potential advantages, the spacing effect has seldom been applied to organized education training or complex motor skill learning where it has the potential to make a significant impact. The purpose of this study was to determine if a resuscitation course taught in a spaced format compared to the usual massed instruction results in improved retention of procedural skills. Methods: EMS providers (Paramedics and Emergency Medical Technicians (EMT)) were block randomized to receive a Pediatric Advanced Life Support (PALS) course in either a spaced format (four 210-minute weekly sessions) or a massed format (two sequential 7-hour days). Blinded observers used expert-developed 4-point global rating scales to assess video recordings of each learner performing various resuscitation skills before, after and 3-months following course completion. Primary outcomes were performance on infant bag-valve-mask ventilation (BVMV), intraosseous (IO) insertion, infant intubation, infant and adult chest compressions. Results: Forty-eight of 50 participants completed the study protocol (26 spaced and 22 massed). There was no significant difference between the two groups on testing before and immediately after the course. 3-months following course completion participants in the spaced cohort scored higher overall for BVMV (2.2 ± 0.13 versus 1.8 ± 0.14, p=0.012) without statistically significant difference in scores for IO insertion (3.0 ± 0.13 versus 2.7± 0.13, p= 0.052), intubation (2.7± 0.13 versus 2.5 ± 0.14, p=0.249), infant compressions (2.5± 0.28 versus 2.5± 0.31, p=0.831) and adult compressions (2.3± 0.24 versus 2.2± 0.26, p=0.728) Conclusion: Procedural skills taught in a spaced format result in at least as good learning as the traditional massed format; more complex skills taught in a spaced format may result in better long term retention when compared to traditional massed training as there was a clear difference in BVMV and trend toward a difference in IO insertion.