A Structural Equation Modeling Approach for the Analysis of Cortisol Data Collected Using Pre–Post–Post Designs

Abstract

This study introduces a novel application of structural equation modeling (SEM) for the analysis of cortisol data that are collected using a pre–post–post design. By way of an extended example, an SEM model is developed that permits an examination of both the overall level of cortisol, as well as changes in cortisol (reactivity and regulation), as predictors of cognitive (executive) and behavioral functioning in 3- to 5-year-old children (N = 171) attending Head Start. The SEM model makes use of the parameterization of latent curve models. Throughout the extended example, the strengths of using an SEM approach for the analysis of cortisol data that are collected using pre–post–post designs is highlighted.     

Computed tomography‐enhanced anatomy course using enterprise visualization

Rapid changes in medical knowledge are forcing continuous adaptation of the basic science courses in medical schools. This article discusses a three‐year experience developing a new Computed Tomography (CT)‐based anatomy curriculum at the Sackler School of Medicine, Tel Aviv University, including describing the motivations and reasoning for the new curriculum, the CT‐based learning system itself, practical examples of visual dissections, and student assessments of the new curriculum. At the heart of this new curriculum is the emphasis on studying anatomy by navigating inside the bodies of various living individuals utilizing a CT viewer. To assess the students’ experience with the new CT‐based learning method, an anonymous questionnaire was administered at the end of the course for three consecutive academic years: 2008/2009, 2009/2010, 2010/2011. Based upon the results, modifications were made to the curriculum in the summers of 2009 and 2010. Results showed that: (1) during these three years the number of students extensively using the CT system quadrupled (from 11% to 46%); (2) students' satisfaction from radiologists involvement increased by 150%; and (3) student appreciation of the CT‐based learning method significantly increased (from 13% to 68%). It was concluded that discouraging results (mainly negative feedback from students) during the first years and a priori opposition from the teaching staff should not weaken efforts to develop new teaching methods in the field of anatomy. Incorporating a new curriculum requires time and patience. Student and staff satisfaction, along with utilization of the new system, will increase with the improvement of impeding factors. Anat Sci Educ 6: 332–341. © 2013 American Association of Anatomists.     

Reconciling multiple sources of influence: Longitudinal associations among perceived parent,closest friend,and popular peer injunctive norms and adolescent substance use

Prospective associations over a 5-year period were examined among perceived parent, closest friend, and popular peer injunctive norms and the onset and frequency of adolescent substance use within a diverse (53% female, 45.5% White non-Hispanic, 22.3% Hispanic, 21.5% Black, 1% Asian, and 6.4% another race) sample of 868 seventh- and eighth-grade adolescents from 2012 to 2017. Analyses revealed adolescents' substance use norms were more lenient than perceptions of their parents' and stricter than perceptions of their closest friends'. Stricter perceptions of parent and closest friend norms, but not popular peer norms, were significantly associated with a later onset of alcohol, marijuana, and cigarette use, and the magnitude of the effect of each source' on later substance use varied across development.     

Instructional design learners make sense of theory: a collaborative autoethnography

Educational technology research and development - Understanding theory is essential to instructional design (ID) research and practice; however, novice designers struggle to make sense of...     

Humor Works in Funny Ways: Examining Satirical Tone as a Key Determinant in Political Humor Message Processing

This multi-experiment study builds upon extant political entertainment theory, testing whether satire type (horatian versus juvenalian) cues varying processing mechanisms (message discounting versus resource allocation), and if consequential differences to argument scrutiny levels or message persuasiveness result. Using novel stimuli (e.g., animated cartoons, study one) and real-world late-night political satire (The Daily Show and The Colbert Report, study two), results suggest that satire type was a key antecedent in political humor message processing. Additionally, the varying mechanisms had differential effects on political argument scrutiny levels and message persuasiveness.     

Factor Structure and Measurement Invariance of the Intragroup Conflict Scale: Validation in Athletic Trainer and Coach Populations

ABSTRACT

The purposes of this study were to examine the factorial validity of the six-item Intragroup Conflict Scale (ICS) in athletic trainer (AT) and coach populations and to examine measurement invariance by gender and profession. A total of 195 ATs and 615 head or assistant coaches working at secondary schools or National Collegiate Athletic Association (NCAA) institutions completed the ICS. Data were analyzed using confirmatory factor analysis procedures in LISREL 10 (Student Edition). Results supported the reliability and validity of the two-factor ICS model among ATs and coaches. Strict measurement invariance was observed when comparing male to female AT responses. Strong measurement invariance was observed when comparing male to female coach responses, as well as AT to coach responses. These data not only support the reliability and validity of the ICS for use in AT and coach populations but also support direct comparisons of mean scores across gender or profession.     

Relationships between training load,injury, and fitness in sub-elite collision sport athletes

Abstract

The purpose of this study was to develop statistical models that estimate the influence of training load on training injury and physical fitness in collision sport athletes. The incidence of training injuries was studied in 183 rugby league players over two competitive seasons. Participants were assessed for height, body mass, skinfold thickness, vertical jump, 10-m, 20-m and 40-m sprint time, agility, and estimated maximal aerobic power in the off-season, pre-season, mid-season, and end-season. Training load and injury data were summarised into pre-season, early-competition, and late-competition training phases. Individual training load, fitness, and injury data were modelled using a logistic regression model with a binomial distribution and logit link function, while team training load and injury data were modelled using a linear regression model. While physical fitness improved with training, there was no association (P = 0.16 – 0.99) between training load and changes in physical fitness during any of the training phases. However, increases in training load during the early-competition training phase decreased (P = 0.04) agility performance. A relationship (P = 0.01 – 0.04) was observed between the log of training load and odds of injury during each training phase, resulting in a 1.50 – 2.85 increase in the odds of injury for each arbitrary unit increase in training load. Furthermore, during the pre-season training phase there was a relationship (P = 0.01) between training load and injury incidence within the training load range of 155 and 590 arbitrary units. During the early and late-competition training phases, increases in training load of 175 – 620 arbitrary units and 145 – 410 arbitrary units, respectively, resulted in no further increase in injury incidence. These findings demonstrate that increases in training load, particularly during the pre-season training phase, increase the odds of injury in collision sport athletes. However, while increases in training load from 175 to 620 arbitrary units during the early-competition training phase result in no further increase in injury incidence, marked reductions in agility performances can occur. These findings suggest that reductions in training load during the early-competition training phase can reduce the odds of injury without compromising agility performances in collision sport athletes.     

Landing ground reaction forces in figure skaters and non-skaters

Abstract

Researchers and clinicians have suggested that overuse injuries to the lower back and lower extremities of figure skaters may be associated with the repeated high impact forces sustained during jump landings. Our primary aim was to compare the vertical ground reaction forces (GRFs) in freestyle figure skaters (n = 26) and non-skaters (n = 18) for the same barefoot single leg landing on a force plate from a 20 cm platform. Compared with non-skaters, skaters exhibited a significantly greater normalised peak GRF (3.50 ± 0.47 × body weight for skaters vs. 3.13 ± 0.45 × body weight for non-skaters), significantly shorter time to peak GRF (81.21 ± 14.01 ms for skaters vs. 93.81 ± 16.49 ms for non-skaters), and significantly longer time to stabilisation (TTS) of the GRF (2.38 ± 0.07 s for skaters vs. 2.22 ± 0.07 s for non-skaters). Skaters also confined their centre of pressure (CoP) to a significantly smaller mediolateral (M–L) (25%) and anterior–posterior (A–P) (40%) range during the landing phase, with the position of the CoP located in the mid to forefoot region. The narrower and more forward position of the CoP in skaters may at least partially explain the greater peak GRF, shorter time to peak, and longer TTS. Training and/or equipment modification serve as potential targets to decrease peak GRF by distributing it over a longer time period. More comprehensive studies including electromyography and motion capture are needed to fully characterise the unique figure skater landing strategy.     

Teaching Mathematical Biology in High School Using Adapted Primary Literature

The study compared the effect of two adaptations of a scientific article on students?? comprehension and use of scientific inquiry skills. One adaptation preserved as much as possible the canonical form of the original article (APL, Adapted Primary Literature) and the other was written in a more narrative mode typical of secondary literature (SL). Both adaptations contained the same content. Two hundred and eleven senior high school students in a Western Canadian school district participated. The numbers of males and females were approximately equal, and all students were registered in an introductory calculus course. All students were given a 90?min class by their teachers that introduced them to the basic mathematical concepts needed to read the articles. Students were randomly assigned to read either the APL or the SL and afterwards to complete a questionnaire, which was common to both groups. Major findings showed that the SL students better understood the article, that the APL students thought more critically about the article, that females understood the article better than males, and that students?? attitudes towards reading the articles, regardless of group, were positively associated with their comprehension and use of inquiry skills. The results coincide in important ways with those of similar studies in Israel, and show that asking students to read text that resembles scientific writing increases their use of critical thinking skills when reading.     

Examining perceived control level and instability as predictors of first-year college students’ academic achievement

The aim of the present study was to examine the intraindividual level and instability of perceived academic control (PC) among first-year college students, and their predictive effects on academic achievement. Two studies were conducted measuring situational (state) PC on different schedules: Study 1 (N = 242) five times over a 6-month period and Study 2 (N = 80) daily over a 2-week period. Consistent across both studies were confirmatory factor analyses and structural equation models demonstrating significant PC instability, as well as negative correlations between intraindividual PC levels (average across measurements) and instability (standard deviation across measurements). Also, in both studies PC level positively predicted subsequent academic achievement, although no significant PC instability first-order effects were found. Both studies revealed a PC level by instability interaction, as students with high-unstable PC typically received poorer grades than high-stable PC students. Study findings highlight the importance of considering both PC level and instability, and identify a previously unknown group of first-year college students at-risk of under-achieving academically – students with high-unstable perceived control.