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A secondary analysis of the School Health Education Evaluation data base.

This secondary analysis examined variables directly related to teacher training not fully examined in the School Health Education Evaluation (SHEE). The problem was to determine the effect of School Health Curriculum Project (SHCP) teacher training and curriculum implementation variables on overall student health knowledge, attitude, and self-reported practice scores in SHCP grades four-six. The major variables of interest had no statistically significant interactive effects on student scores in the knowledge, attitude, and practice domains. The teacher implementation variable had significant (p less than or equal to .05) main effects on student scores within attitude and practice domains in addition to statistically significant effects on related subscores within categorical item areas. Design flaws, which represent serious threats to internal and external validity of the primary analysis, may have effected results associated with this project.

Curriculum↗

Graphical exploratory data analysis of RNA secondary structure dynamics predicted by the massively parallel genetic algorithm.

Studies indicate that RNA may enter intermediate and multiple conformational states, which may impact gene expression and molecular function. It is known that the biologically functional states of RNA molecules may not correspond to their minimum energy conformations, that kinetic barriers may trap the molecule in a local minimum, that folding often occurs during transcription, and that cases exist in which a molecule will transition between one or more functional conformations. Thus, methods for simulating the folding pathway and dynamic behavior of an RNA molecule are important for the prediction of RNA structure and its associated functions. We have developed several data mining techniques guided by interactive visualization tools associated with our massively parallel genetic algorithm for RNA/DNA secondary structure prediction, MPGAfold, and StructureLab analysis workbench. Most of the methods and tools are also applicable to dynamic programming algorithm (DPA) folding data analysis. When applied to MPGAfold results these methodologies are used to determine the significant intermediate and final structures associated with co-transcriptional and full length RNA folding. Since the genetic algorithm is essentially stochastic, multiple runs are required to develop a consensus understanding of an RNA structure. The interactive visualizations facilitate interpretation of results from sequential or full length individual MPGAfold runs, final results of multiple folding runs, including multiple population sizes, and the results from multiple RNA sequences of one family. This paper describes several of these techniques and shows how they are used to help solve this highly combinatoric problem.

Algorithms↗

Sexual abstinence, contraception, and condom use by young African women: a secondary analysis of survey data.

BACKGROUND: Drug therapy for people with AIDS is a humanitarian priority but prevention of HIV infection remains essential. Focusing on young single African women, we aimed to assess trends in a set of behaviours-sexual abstinence, contraceptive use, and condom use-that are known to affect the rates of HIV transmission. METHODS: We did a secondary analysis of public-access data sets in 18 African countries (132,800 women), and calculated changes in a set of behavioural indicators over time. We standardised these trends from nationally representative surveys to adjust for within-country changes in age, education, and type of residential location. FINDINGS: Between about 1993 and 2001, the percentage of women reporting no sexual experience changed little. During the same period, the percentage of sexually experienced women who reported no sexual intercourse in the previous 3 months (secondary abstinence) rose significantly in seven of 18 countries and the median for all 18 countries increased from 43.8% to 49.2%. Use of condoms for pregnancy prevention rose significantly in 13 of 18 countries and the median proportion increased from 5.3% to 18.8%. The median rate of annual increase of condom use was 1.41 percentage points (95% CI 1.12-2.25). In the 13 countries with available data, condom use at most recent coitus rose from a median of 19.3% to 28.4%. Over half (58.5%) of condom users were motivated, at least in part, by a wish to avoid pregnancy. INTERPRETATION: Condom promotion campaigns in sub-Saharan Africa have affected the behaviour of young single women; the pace of change has matched the rise in contraceptive use by married couples in developing countries over recent decades. Thus continuing efforts to promote condom use with emphasis on pregnancy prevention are justified.

Adolescent↗

Linking stress and injury in the farming environment: a secondary analysis of qualitative data.

The first step in injury prevention is to understand the injury problem. This includes examining the nature of the problem from the perspective of the target community. This article uses qualitative methods to explain the nature of the injury problem and identifies prevention strategies through a three-step process: identify a causal model, validate the model, and identify strategies using the causal model. A causal model linking safety performance and safety demand, health decision making, and occupational stress was derived by secondary analysis of farm family focus group data (step 1) and validated by other farm family focus groups (step 2). Prevention strategies identified from the causal model (step 3) include decreasing the number of roles performed exclusively by one individual, developing an easy-to-use planning tool that assists farmers in anticipating and reducing future work demands, and developing an education module that incorporates injury costs into safety decision making.

Accidents, Occupational↗

The contribution of primary care systems to health outcomes within Organization for Economic Cooperation and Development (OECD) countries, 1970-1998.

OBJECTIVE: To assess the contribution of primary care systems to a variety of health outcomes in 18 wealthy Organization for Economic Cooperation and Development (OECD) countries over three decades. DATA SOURCES/STUDY SETTING: Data were primarily derived from OECD Health Data 2001 and from published literature. The unit of analysis is each of 18 wealthy OECD countries from 1970 to 1998 (total n = 504). STUDY DESIGN: Pooled, cross-sectional, time-series analysis of secondary data using fixed effects regression. DATA COLLECTION/EXTRACTION METHODS: Secondary analysis of public-use datasets. Primary care system characteristics were assessed using a common set of indicators derived from secondary datasets, published literature, technical documents, and consultation with in-country experts. PRINCIPAL FINDINGS: The strength of a country's primary care system was negatively associated with (a) all-cause mortality, (b) all-cause premature mortality, and (c) cause-specific premature mortality from asthma and bronchitis, emphysema and pneumonia, cardiovascular disease, and heart disease (p<0.05 in fixed effects, multivariate regression analyses). This relationship was significant, albeit reduced in magnitude, even while controlling for macro-level (GDP per capita, total physicians per one thousand population, percent of elderly) and micro-level (average number of ambulatory care visits, per capita income, alcohol and tobacco consumption) determinants of population health. CONCLUSIONS: (1) Strong primary care system and practice characteristics such as geographic regulation, longitudinality, coordination, and community orientation were associated with improved population health. (2) Despite health reform efforts, few OECD countries have improved essential features of their primary care systems as assessed by the scale used here. (3) The proposed scale can also be used to monitor health reform efforts intended to improve primary care.

Cross-Sectional Studies↗

The ECASS 3-hour cohort. Secondary analysis of ECASS data by time stratification. ECASS Study Group. European Cooperative Acute Stroke Study.

OBJECTIVES: (1) To determine whether and how outcome measurements in the ECASS trial are influenced by a shorter time window (0-3 vs. 3-6 h) between onset of symptoms and start of thrombolytic therapy using recombinant tissue plasminogen activator (rt-PA) in acute ischemic stroke. (2) To discuss the results of the ECASS 0- to 3-hour cohort with the results of the National Institute of Neurological Disorders and Stroke Study (NINDSS). DESIGN AND ANALYSIS: Analysis of the 0- to 3-hour and the 3- to 6-hour cohort in accordance with the ECASS protocol. Comparative analysis of the ECASS and NINDSS results following the NINDSS protocol using dichotomized endpoints. MAIN OUTCOME MEASURES: Primary endpoints: modified Rankin Scale, Barthel Index; secondary endpoints: combined Barthel/Rankin, long-term Scandinavian Stroke Scale, National Institutes of Health Stroke Scale, mortality at 30 and 90 days, occurrence of intracranial hemorrhage. NINDS trial endpoint: favorable outcome as defined in the NINDS trial. RESULTS: In ECASS, 87 patients were randomized within 3 h of stroke onset. Differences in favor of rt-PA treatment can be found for all primary and secondary outcome measures in the ECASS 0- to 3-hour cohort, except for mortality at day 30, which is somewhat higher in the rt-pA-treated group. However, due to the small sample size, the differences do not reach statistical significance. Early infarct signs (as defined by the ECASS protocol) are found as early as 2 h after stroke onset. Parenchymal hemorrhages are found significantly more often among rt-PA-treated patients. The results in the ECASS 0- to 3-hour cohort fit well with the results in NINDSS. CONCLUSION: Data from the 3-hour ECASS cohort support the efficacy of early thrombolytic therapy in acute hemispheric stroke patients. Comparing bleeding complications between the ECASS and NINDSS is difficult because of differences in the definition and occurrence of hemorrhagic events.

Aged↗

Secondary analysis of economic data: a review of cost-benefit studies of neonatal screening for phenylketonuria.

STUDY OBJECTIVE: To estimate the net financial benefit of neonatal screening for phenylketonuria (PKU): by a simple pooling of cost data from the literature; and by a more complex modelling approach. DESIGN: A systematic literature review was conducted to identify papers containing data on the monetary costs and benefits of neonatal screening for PKU. The methodological quality of the studies was appraised, and data were extracted on resource use and expenditure. Monetary data were converted to common currency units, and standardised to UK incidence rates. Net benefits were calculated for median, best case and worst case scenarios, and the effect of excluding poor quality studies and data was tested. The net benefit was also estimated from a model based on data from the literature and assumptions appropriate for the current UK situation. Extensive sensitivity analysis was conducted. MAIN RESULTS: The direct net benefit of screening based on the median costs and benefits from the 13 studies identified was 143,400 Pounds per case detected and treated (39,000 Pounds and 241,800 Pounds for worst case and best case scenarios respectively). The direct net benefit obtained by the modelling approach was lower at 93,400 Pounds per case detected and treated. Screening remained cost saving under sensitivity analysis, except with low residential care costs (less than 12,300 Pounds per annum), or very low incidence rates (less than 1 in 27,000). CONCLUSIONS: The economic literature on PKU screening is of variable quality. The two methods of secondary analysis lead to the same conclusion: that neonatal PKU screening is worthwhile in financial terms alone in the UK, and that it justifies the infrastructure for collecting and testing neonatal blood samples. This result cannot necessarily be extrapolated to other countries.

Cost-Benefit Analysis↗

Effects of sex, age, and visits on receipt of preventive healthcare services: a secondary analysis of national data.

BACKGROUND: Sex and age may exert a combined influence on receipt of preventive services with differences due to number of ambulatory care visits. METHODS: We used nationally representative data to determine weighted percentages and adjusted odds ratios of men and women stratified by age group who received selected preventive services. The presence of interaction between sex and age group was tested using adjusted models and retested after adding number of visits. RESULTS: Men were less likely than women to have received blood pressure screening (aOR 0.44;0.40-0.50), cholesterol screening (aOR 0.72;0.65-0.79), tobacco cessation counseling (aOR 0.66;0.55-0.78), and checkups (aOR 0.53;0.49-0.57). In younger age groups, men were particularly less likely than women to have received these services. In adjusted models, this observed interaction between sex and age group persisted only for blood pressure measurement (p = .016) and routine checkups (p < .001). When adjusting for number of visits, the interaction of age on receipt of blood pressure checks was mitigated but men were still overall less likely to receive the service. CONCLUSION: Men are significantly less likely than women to receive certain preventive services, and younger men even more so. Some of this discrepancy is secondary to a difference in number of ambulatory care visits.

Adult↗

Parasite clearance in patients with Plasmodium vivax monoinfection treated with artesunate in Cambodia: an observational secondary analysis of trial data.

BACKGROUND: Artemisinin-based combination therapies are the frontline drugs for the treatment of malaria infections, but, for Plasmodium falciparum, the efficacy of artemisinin is threatened by the spread of resistance. Plasmodium vivax is the second most common cause of human malaria, but there is little information on its susceptibility to artemisinin due to the lack of an in-vitro culture system. This study aims to characterise the response of P vivax to artesunate using clinical, genomic, and transcriptomic data from infected individuals in Cambodia. METHODS: We analysed 161 P vivax infections from 87 patients (six female and 81 male; median age 20 years [IQR 17-26]) enrolled between Nov 10, 2021, and Nov 18, 2022, in a drug efficacy study in Cambodia and treated with 2 mg/kg/day of artesunate for 7 days. To determine clearance rates, we measured parasitaemia before, and 1 h, 2 h, 4 h, 8 h, and 16 h after the first dose of artesunate, and then at 24-h intervals during the 7 days of artesunate therapy. We also examined the parasites' genome sequences and used RNA sequencing of 31 infections to analyse changes in parasite gene expression upon treatment. FINDINGS: All infections were successfully cleared by day 3. However, 49 of the infections displayed a slow clearance after treatment, including nine (6%) infections with a parasite clearance slope half-life greater than 5 h. We observed no significant association between slow clearance and either patient or infection characteristics (including the infection's stage composition). Analyses of gene expression showed that, while fast-clearing parasites displayed significant changes in gene expression immediately upon treatment, slow-clearing parasites had a delayed gene expression response characterised notably by a downregulation of genes associated with haemoglobin endocytosis and digestion. INTERPRETATION: Some Cambodian P vivax parasites clear slowly after artesunate treatment, possibly due to a downregulation of haemoglobin metabolism that might reduce the efficiency of the artesunate. The slow clearance could allow parasites to outlast artesunate treatment and facilitate emergence of resistance to the artemisinin-combination therapy partner drug, threatening malaria elimination effort. FUNDING: US National Institutes of Health.

Adolescent↗

Methodologies used in nursing research designed to improve patient safety.

Nursing research studies of patient safety for 2002-2005 were reviewed to determine methods used and methodological challenges within this field of research. Methods used in traditional clinical research and in health services research were often combined or adapted in innovative research designs to advance knowledge regarding nursing care and patient safety outcomes. This relatively new focus of complex research posed methodological challenges in areas such as measurement and the availability and analysis of data. The most frequent methods used included survey research, analysis of secondary data, and observational studies. This review points to the need to increase the incorporation of complex methodological training, including health services research, the analysis of secondary data and complex survey design in our doctoral programs, and to provide opportunities for researchers to gain further methodological training. Increased use of multi-site and multi-level studies is also needed.

Anthropology, Cultural↗

Health status and medical consumption of the elderly in urban and rural areas in The Netherlands; a secondary analysis of CBS-data.

Data of the life situation survey of the Central Bureau of Statistics (CBS) of 1982 have been analysed. This secondary analysis has been carried out to study differences in health and medical consumption between urban and rural elderly. Two contrasting groups of elderly have been used: urban and rural elderly. It has been found that there are no differences in the prevalence of chronic disorders. More mental complaints have been found among male urban elderly compared to male rural elderly. The same relationship, although not significant, exists for women. For women it has been found that urban elderly feel less healthy than rural elderly. Male urban elderly aged 55-74 year pay more visits to the general practitioner than rural elderly of the same age. The same holds for women aged 75 year and over who also pay more visits to the physician.

Aged↗

Secondary structure determination of proteins in aqueous solution by infrared spectroscopy: a comparison of multivariate data analysis methods.

The accuracy of the secondary structure prediction from an infrared spectra data base of 39 proteins with known X-ray structure was investigated by different methods of multivariate data analysis. The best agreements with the secondary structure determined by X-ray crystallography are obtained if both the amide I and amide II bands are used for calibration. With optimized parameters the methods singular value decomposition, partial least squares, and ridge regression yield similar results. As judged by the standard error of prediction, the secondary structure elements helix and beta-sheet can be predicted with the highest accuracy. Small data sets of less than 20 protein spectra, which exhibit the variance in secondary structure content of the whole set, can pretend an increased prediction accuracy only if column cross-validation is used as reference; however, with these calibration sets the average secondary structure prediction of all 39 proteins is debased. The hydrogen-bonded turns or bridges are predicted with higher accuracy than the assigned secondary structure types helix and beta-sheet.

Multivariate Analysis↗

Proposal for the creation of a Web-based heterogeneous distributed archive for psychological data.

This report presents a proposal to create archives of data from psychological research and associated metadata Web pages and link them into a heterogeneous distributed archive on the World-Wide Web. Several specific recommendations are made concerning some of the issues faced by the data archivist and data archive user hoping to use the Web. In particular, a recommendation is made to create a publicly accessible Web page for each data set and place keywords, experimental methods, data descriptions, pointers to journal articles, and pointers to other archive Web pages pertinent to this data set on this metadata Web page. If the archivist includes a special keyword (PsychologyDataArchive) on the metadata Web page, Web-based search engines will automatically be able to subset all participating data archives for indexing and semantic analysis. The secondary data analyst can then include the word PsychologyDataArchive in his Web search and will be able to effectively find relevant participating Web data archives.

Archives↗

The kappa statistic for establishing interrater reliability in the secondary analysis of qualitative clinical data.

Analysis of extant clinical records is receiving increased emphasis in nursing investigations. Appropriate use of this approach to patient research requires careful attention to data management, including assessment of reliability. Percent agreement, phi, and Kappa all serve as estimates of interrater reliability in the analysis of data. Kappa has particular merit as a measure of interrater reliability; it also has some peculiar problems in implementation and interpretation. The nature and computation of Kappa and its application in analysis of clinical data are discussed.

Data Collection↗