Assessing Marijuana Use,Anxiety, and Academic Performance Among College Students

This article examines the relationship between marijuana use and anxiety symptoms among college students, with a secondary focus on marijuana use and grade point average (GPA). A secondary analysis was conducted on data obtained from the American College Health Association–National College Health Assessment. Results indicated that marijuana use was negatively associated with GPA among students with current anxiety and no formal treatment. The relationships between these variables may be more complex than previously thought.     

Predicting University Students’ Academic Success and Major Using Random Forests

Research in Higher Education - In this article, a large data set containing every course taken by every undergraduate student in a major university in Canada over 10 years is analysed. Modern...     

Concurrent and predictive validity of the LET-II for average children

Memory tests, such as the Learning Efficiency Test-II (LET-II), have frequently been used to describe the memory characteristics of special populations such as persons with learning disabilities, brain damage, or Alzheimer's disease. Yet, few research studies have examined the memory characteristics of normally functioning children and compared these characteristics to their performance on ability tests or real-life achievement criteria. This study investigates the predictive and concurrent validities of the LET-II for performance on the Kuhlmann-Anderson Tests (K-A), class grades, and actual grade level functioning in reading and mathematics for third and fourth grade children of average intelligence. The LET-II memory factor scores correlated significantly with the K-A scores, class grades and actual grade level functioning in reading. The relevance of these findings for norm-referenced psychological tests, and in particular memory tests, in real-life settings is examined. © 1996 John Wiley & Sons, Inc.     

Factorial Invariance of the Abbreviated Neighborhood Environment Walkability Scale among Senior Women in the Nurses’ Health Study Cohort

The purpose of this study was to examine the factorial invariance of the Abbreviated Neighborhood Environment Walkability Scale (NEWS-A) across subgroups based on demographic, health-related, behavioral, and environmental characteristics among Nurses’ Health Study participants (N = 2,919; age M = 73.0, SD = 6.9 years) living in California, Massachusetts, and Pennsylvania. A series of multigroup confirmatory factor analyses were conducted to evaluate increasingly restrictive hypotheses of factorial invariance. Factorial invariance was supported across age, walking limitations, and neighborhood walking. Only partial scalar invariance was supported across state residence and neighborhood population density. This evidence provides support for using the NEWS-A with older women of different ages, who have different degrees of walking limitations, and who engage in different amounts of neighborhood walking. Partial scalar invariance suggests that researchers should be cautious when using the NEWS-A to compare older adults living in different states and neighborhoods with different levels of population density.     

The relationship between the Luria-Nebraska neuropsychological battery-children's revision and the Minnesota Percepto-Diagnostic Test with learning disabled students

The Luria-Nebraska Neuropsychological Battery-Children's Revision (LNNB-Children's Revision) and The Minnesota Percepto-Diagnostic Test (MPD) were administered to 40 learning disabled (LD) students. Correlations were run between the scales of the LNNB-Children's Revision and MPD scores across the sample. Coefficients ranged from .07 to .71 for the intercorrelations of the scales of the LNNB-Children's Revision. Low correlations (−.10 to −.27) were found between MPD T scores and the LNNB-Children's Revision Scales, but raw scores from the MPD had somewhat higher correlations with the LNNB (.18 to .65).     

The influence of self-determination in physical education on leisure-time physical activity behavior

Using a multitheory approach, this study was designed to investigate the influence of urban adolescents' perceived autonomy and competence in physical education on their physical activity intentions and behaviors during leisure time. A transcontextual model was hypothesized and tested. Urban adolescents (N=653, ages 11-15 years) completed questionnaires assessing relevant psychological constructs and moderate to vigorous physical activity and then had their cardiorespiratory fitness assessed with the Progressive Aerobic Cardiovascular Endurance Run (PACER) test. Based on our structural equation modeling analyses and fit indexes, the transcontextual model adequately fit the data. We concluded that the two theoretical frameworks--SDT and theory of planned behavior--can be integrated to provide an enhanced understanding of the influence of physical education on leisure-time physical activity. The results revealed that perceived autonomy and competence in physical education are interrelated and function as a whole for enhancing leisure-time physically active intentions and behavior.     

Repeated retention testing effects do not generalize to a contextual interference protocol

Three experiments examined repeated retention testing effects in a contextual interference (CI) protocol. Retention was assessed at 10 min and 24 hr following acquisition or at just 24-hr for the one-test conditions. Experiments 1 and 2 used speeded-response key-pressing tasks. Dependent measures were total time and errors. Experiment 3 used sequential-timing tasks. Dependent measures were absolute error and absolute constant error Results revealed CI effects in each experiment. Repeated retention testing effects were not found in Experiments 1 and 3. Experiment 2 revealed superior performance by the two-test condition compared to the one-test condition. This result was qualified by possible practice effects during the 10-min test. It was concluded that repeated retention testing does not present problems for most studies of CI.     

Carbohydrate and carbohydrate + protein for cycling time-trial performance

Carbohydrate intake during endurance exercise delays the onset of fatigue and improves performance. Two recent cycling studies have reported increased time to exhaustion when protein is ingested together with carbohydrate. The purpose of the present study was to test the hypothesis that ingestion of a carbohydrate + protein beverage will lead to significant improvements in cycling time-trial performance relative to placebo and carbohydrate alone. Thirteen cyclists completed 120 min of constant-load ergometer cycling. Thereafter, participants performed a time-trial in which they completed a set amount of work (7 kJ kg(-1)) as quickly as possible. Participants completed four experimental trials, the first for familiarization and then three randomized, double-blind treatments consisting of a placebo, carbohydrate, and carbohydrate + protein. Participants received 250 ml of beverage every 15 min during the constant-load ride. Time-trial performance for carbohydrate (37.1 min, s = 3.8) was significantly (P < 0.05) faster than placebo (39.7 min, s = 4.6). Time-trial performance for carbohydrate + protein (38.8 min, s = 5.5) was not significantly different from either placebo or carbohydrate. Ingestion of a carbohydrate beverage during two hours of constant-load cycling significantly enhanced subsequent time-trial performance compared with placebo. The carbohydrate + protein beverage provided no additional performance benefit.