Relations between numerical, spatial, and executive function skills and mathematics achievement: A latent-variable approach.

Current evidence suggests that numerical, spatial, and executive function (EF) skills each play critical and independent roles in the learning and performance of mathematics. However, these conclusions are largely based on isolated bodies of research and without measurement at the latent variable level. Thus, questions remain regarding the latent structure and potentially shared and unique relations between numerical, spatial, EF, and mathematics abilities. The purpose of the current study was to (i) confirm the latent structure of the hypothesized constructs of numerical, spatial, and EF skills and mathematics achievement, (ii) measure their unique and shared relations with one another, and (iii) test a set of novel hypotheses aimed to more closely reveal the underlying nature of the oft reported space-math association. Our analytical approach involved latent-variable analyses (structural equation modeling) with a sample of 4- to 11-year-old children (N = 316, Mage = 6.68 years). Results of a confirmatory factor analysis demonstrated that numerical, spatial, EF, and mathematics skills are highly related, yet separable, constructs. Follow-up structural analyses revealed that numerical, spatial, and EF latent variables explained 84% of children's mathematics achievement scores, controlling for age. However, only numerical and spatial performance were unique predictors of mathematics achievement. The observed patterns of relations and developmental trajectories remained stable across age and grade (preschool - 4th grade). Follow-up mediation analyses revealed that numerical skills, but not EF skills, partially mediated the relation between spatial skills and mathematics achievement. Overall, our results point to spatial visualization as a unique and robust predictor of children's mathematics achievement.

Use and attitudes of obstetricians toward 3 high-risk interventions in MFMU Network hospitals.

OBJECTIVE: We sought to evaluate the frequency of, and factors associated with, the use of 3 evidence-based interventions: antenatal corticosteroids for fetal lung maturity, progesterone for prevention of recurrent preterm birth, and magnesium sulfate for fetal neuroprotection. STUDY DESIGN: A self-administered survey was conducted from January through May 2011 among obstetricians from 21 hospitals that included 30 questions regarding their knowledge, attitudes, and practice of the 3 evidence-based interventions and the 14-item short version of the Team Climate for Innovation survey. Frequency of use of each intervention was ascertained from an obstetrical cohort of women between January 2010 and February 2011. RESULTS: A total of 329 obstetricians (74% response rate) who managed 16,946 deliveries within the obstetrical cohort participated in the survey. More than 90% of obstetricians reported that they incorporated each intervention into routine practice. Actual frequency of administration in women eligible for the treatments was 93% for corticosteroids, 39% for progesterone, and 71% for magnesium sulfate. Provider satisfaction with quality of treatment evidence was 97% for corticosteroids, 82% for progesterone, and 57% for magnesium sulfate. Obstetricians perceived that barriers to treatment were most frequent for progesterone (76%), 30% for magnesium sulfate, and 17% for corticosteroids. Progesterone use was more frequent among patients whose provider reported the quality of the evidence was above average to excellent compared with poor to average (42% vs 25%, respectively; P < .001), and they were satisfied with their knowledge of the intervention (41% vs 28%; P = .02), and was less common among patients whose provider reported barriers to hospital or pharmacy drug delivery (31% vs 42%; P = .01). Corticosteroid administration was more common among patients who delivered at hospitals with 24 hours a day-7 days a week maternal-fetal medicine specialist coverage (93% vs 84%; P = .046), CONCLUSION: Obstetricians in Maternal-Fetal Medicine Units Network hospitals frequently use these evidence-based interventions; however, progesterone use was found to be related to their assessment of evidence quality. Neither progesterone nor the other interventions were associated with overall climate of innovation within a hospital as measured by the Team Climate for Innovation. National Institutes of Health Consensus Conference Statements may also have an impact on use; there is such a statement for antenatal corticosteroids but not for progesterone for preterm prevention or magnesium sulfate for fetal neuroprotection.

Maternal tobacco use is associated with increased markers of oxidative stress in the placenta.

OBJECTIVE: We sought to extend our prior observations and histopathologically characterize key metabolic enzymes (CYP1A1) with markers of oxidative damage in the placental sections from smokers. STUDY DESIGN: Placental specimens were collected from term singleton deliveries from smokers (n = 10) and nonsmokers (n = 10) and subjected to a detailed histopathological examination. To quantify the extent of oxidative damage, masked score-graded (0-6) histopathology against 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxydeoxyguanisine (8-OHdG) was performed. Minimal significance (P < .05) was determined with a Fisher's exact and a 2-tailed Student t test as appropriate. RESULTS: We observed a significant increase in the presence of syncytial knots in placentas from smokers (70% vs 10%, P = .02). These gross observations were accompanied by a significant aberrant placental aromatic hydrocarbon metabolism (increased CYP1A1, 4.4 vs 2.1, P = .002) in addition to evidence of oxidative damage (4-HNE 3.4 vs 1.1, P = .00005; 8-OHdG 4.9 vs 3.1, P = .0038). CONCLUSION: We observed a strong association between maternal tobacco use and aberrant placental metabolism, syncytial knot formation, and multiple markers of oxidative damage.

Administration of local anesthetic agents to decrease pain associated with peripheral vascular access.

The purpose of this study was to compare a variety of local anesthetic agents before starting an intravenous (i.v.) device to determine which method is the most comfortable for patients. Using a randomized, double-blind, placebo-controlled, pretest-posttest experimental design, the study compared 5 treatment groups (anesthetic spray, placebo spray, anesthetic intradermal injection, placebo intradermal injection, and a control group with no local anesthetic agent) in 84 emergency department patients. Pain was measured with a visual analog scale before and after the application of the local anesthetic agents and after i.v. insertion. Pain was significantly higher in the anesthetic intradermal injection group 1 minute after anesthetic application compared with the other treatment groups. Pain ratings 3 minutes after i.v. insertion were found to be similar for the 5 treatment groups. These study results do not support the use of intradermal anesthetic agents before i.v. catheter insertion.