Predictors of National Differences in Mathematics and Science Achievement: Data From TIMSS for Eighth Grade Students

There is widespread belief that national economic productivity is related to student performance in mathematics and science. With the advent in the 1960s of international surveys of student achievement in math and science, cross-national comparisons have become possible and nations have aspired to become world class in this respect. A major national policy issue in the U.S. and elsewhere is to identify and implement actions to attain and maintain a high level of student achievement in math and science in international comparisons. The math and science project reported here was designed to capitalize on the potential for cross-national research with the Third International Mathematics and Science Study (TIMSS). TIMSS demonstrated that there are wide differences among nations in average student knowledge of math and science at several grade levels. Accordingly, a major research problem is to explain the sources of these national differences; that is, to identify the national-level variables that are the strongest predictors of national differences in average achievement scores. This problem was investigated to generate new research-based knowledge relevant to policy making about math and science education

The Role of Student Attitudes and Beliefs About Mathematics and Science Learning in Academic Achievement: Evidence From TIMSS for Six Nations

In view of the prevalent belief among parents, educators, and policy makers that positive student attitudes and beliefs about mathematics learning are associated with higher academic achievement, Turner and Boe (1999) recently examined this association using data from the Third International Mathematics and Science Study (TIMSS) for seventh- and eighth-grade students in the United States. In light of the substantial support found by Turner and Boe for such attitude-achievement relationships under statistically controlled conditions, the research reported here was designed to expand upon the prior study by quantifying the strength of these relationships in both mathematics and science and to extend the analysis to other nations. To examine cross-national similarities and differences in attitude-achievement relationships, Singapore, Korea, and Hong Kong (representing the Peoples\u27 Republic of China 1) were selected from the East, and Switzer­land, Germany, and the United States were selected from the West

Drug Use and Receipt of Highly Active Antiretroviral Therapy among HIV-Infected Persons in Two U.S. Clinic Cohorts

Drug use and receipt of highly active antiretroviral therapy (HAART) were assessed in HIV-infected persons from the Comprehensive Care Center (CCC; Nashville, TN) and Johns Hopkins University HIV Clinic (JHU; Baltimore, MD) between 1999 and 2005.Participants with and without injection drug use (IDU) history in the CCC and JHU cohorts were evaluated. Additional analysis of persons with history of IDU, non-injection drug use (NIDU), and no drug use from CCC were performed. Activity of IDU and NIDU also was assessed for the CCC cohort. HAART use and time on HAART were analyzed according to drug use category and site of care.1745 persons were included from CCC: 268 (15%) with IDU history and 796 (46%) with NIDU history. 1977 persons were included from JHU: 731 (35%) with IDU history. Overall, the cohorts differed in IDU risk factor rates, age, race, sex, and time in follow-up. In multivariate analyses, IDU was associated with decreased HAART receipt overall (OR = 0.61, 95% CI: [0.45-0.84] and OR = 0.58, 95% CI: [0.46-0.73], respectively for CCC and JHU) and less time on HAART at JHU (0.70, [0.55-0.88]), but not statistically associated with time on HAART at CCC (0.78, [0.56-1.09]). NIDU was independently associated with decreased HAART receipt (0.62, [0.47-0.81]) and less time on HAART (0.66, [0.52-0.85]) at CCC. These associations were not altered significantly whether patients at CCC were categorized according to historical drug use or drug use during the study period.Persons with IDU history from both clinic populations were less likely to receive HAART and tended to have less cumulative time on HAART. Effects of NIDU were similar to IDU at CCC. NIDU without IDU is an important contributor to HAART utilization

Antiretroviral Therapy Initiation Before, During, or After Pregnancy in HIV-1-Infected Women: Maternal Virologic, Immunologic, and Clinical Response

Pregnancy has been associated with a decreased risk of HIV disease progression in the highly active antiretroviral therapy (HAART) era. The effect of timing of HAART initiation relative to pregnancy on maternal virologic, immunologic and clinical outcomes has not been assessed.We conducted a retrospective cohort study from 1997–2005 among 112 pregnant HIV-infected women who started HAART before (N = 12), during (N = 70) or after pregnancy (N = 30).0.01). There were no statistical differences in rates of HIV disease progression between groups.HAART initiation during pregnancy was associated with better immunologic and virologic responses than initiation after pregnancy

Drug use and receipt of highly active antiretroviral therapy among HIV-infected persons in two U.S. clinic cohorts

Objective: Drug use and receipt of highly active antiretroviral therapy (HAART) were assessed in HIV-infected persons from the Comprehensive Care Center (CCC; Nashville, TN) and Johns Hopkins University HIV Clinic (JHU; Baltimore, MD) between 1999 and 2005. Methods: Participants with and without injection drug use (IDU) history in the CCC and JHU cohorts were evaluated. Additional analysis of persons with history of IDU, non-injection drug use (NIDU), and no drug use from CCC were performed. Activity of IDU and NIDU also was assessed for the CCC cohort. HAART use and time on HAART were analyzed according to drug use category and site of care. Results: 1745 persons were included from CCC: 268 (15%) with IDU history and 796 (46%) with NIDU history. 1977 persons were included from JHU: 731 (35%) with IDU history. Overall, the cohorts differed in IDU risk factor rates, age, race, sex, and time in follow-up. In multivariate analyses, IDU was associated with decreased HAART receipt overall (OR = 0.61, 95% CI: [0.45-0.84] and OR = 0.58, 95% CI: [0.46-0.73], respectively for CCC and JHU) and less time on HAART at JHU (0.70, [0.55-0.88]), but not statistically associated with time on HAART at CCC (0.78, [0.56-1.09]). NIDU was independently associated with decreased HAART receipt (0.62, [0.47-0.81]) and less time on HAART (0.66, [0.52-0.85]) at CCC. These associations were not altered significantly whether patients at CCC were categorized according to historical drug use or drug use during the study period. Conclusions: Persons with IDU history from both clinic populations were less likely to receive HAART and tended to have less cumulative time on HAART. Effects of NIDU were similar to IDU at CCC. NIDU without IDU is an important contributor to HAART utilization. © 2011 McGowan et al

Flow chart for patient selection.

<p>HAART: Highly active antiretroviral therapy.</p

Demographic and clinical characteristics of the study population (N = 112).

<p>Note: HAART: highly active antiretroviral therapy. IQR: interquartile range. CD4+ lymphocyte count nadir: the lowest CD4+ lymphocyte count while in care. ADE: AIDS-defining event. IDU: history of injection drug use as a risk factor for HIV infection acquisition. HCV: hepatitis C virologic status prior to first HAART initiation. NA: not available. ART: antiretroviral therapy. PI: protease inhibitor. NNRTI: non-nucleoside reverse transcriptase inhibitor.</p>*<p>The reference group.</p>a<p>Continuous data were compared by Kruskal-Wallis test. Categorical data were compared by 2-sided Fisher's exact test.</p

Estimated rate of HIV-1 RNA and CD4+ lymphocyte change.

<p>The estimated rate of HIV-1 RNA decline and CD4+ lymphocyte increase (small circles) and 95% confidence interval (vertical bars) by pregnancy group over the 6 months following HAART initiation, adjusted for baseline CD4+ lymphocyte count and HIV-1 RNA, age, race, CD4+ lymphocyte count nadir, prior ADE, prior use of non-HAART ART, HAART type, prior pregnancies, and date of HAART start. Horizontal lines represent <i>p-</i>values in a pair-wise comparison (women who started HAART during pregnancy as a reference). Left panel: The estimated rate of HIV-1 RNA decline: −0.32 log₁₀ copies/mL (95% CI −1.45, 0.81) in women who started HAART before pregnancy, −0.35 log₁₀ copies/mL (95% CI −0.57, −0.13) in women who started HAART during pregnancy, and 0.10 log₁₀ copies/mL (95% CI −0.46, 0.66) in women who started HAART after pregnancy. Right panel: The estimated rate of CD4+ lymphocyte increase: estimates were 155.8 cells/mm³ (95% CI −107.6, 419.2) in women who started HAART before pregnancy, 183.8 cells/mm³ (95% CI 110.8, 256.9) in women who started HAART during pregnancy, and −70.8 cells/mm³ (95% CI −326.8, 185.3) in women who started HAART after pregnancy.</p

Kaplan-Meier survival curve of progression to new AIDS-defining event or death by timing of HAART initiation.

<p>The numbers of women at risk each year are also given.</p

Unadjusted CD4+ lymphocyte count change.

<p>Unadjusted CD4+ lymphocyte count following first HAART initiation for each woman (gray lines) and average increase (solid black line) by timing of HAART initiation.</p