Sample design, sampling weights, imputation, and variance estimation in the 1995 National Survey of Family Growth

OBJECTIVES: Cycle 5 of the National Survey of Family Growth (NSFG) was conducted by the National Center for Health Statistics (NCHS) in 1995. The NSFG collects data on pregnancy, childbearing, and women's health from a national sample of women 15-44 years of age. This report describes how the sample was designed, shows response rates for various subgroups of women, describes how the sampling weights were computed to make national estimates possible, shows how missing data were imputed for a limited set of key variables, and describes the proper ways to estimate sampling errors from the NSFG. The report includes both nontechnical summaries for readers who need only general information and more technical detail for readers who need an in-depth understanding of these topics. METHODS: The 1995 NSFG was based on a national probability sample of women 15-44 years of age in the United States and was drawn from 14,000 households interviewed in the 1993 National Health Interview Survey (NHIS). Of the 13,795 women eligible for the NSFG, 10,847 (79 percent) gave complete interviews. RESULTS: This report recommends using weighted data for analysis and a software package that will estimate sampling errors from complex samples (for example, SUDAAN or comparable software). The rate of missing data in the 1995 NSFG was very low. However, missing data were imputed for 315 key variables, called "recodes." Of the 315 recodes defined for Cycle 5, 271 variables had missing data on less than 1 percent of the cases; only 44 had 1 percent or more with missing data. These missing values were imputed for all of these 315 variables. The imputation procedures are described in this report.     

Syndromes, antecedents, and outcomes of psychosis: A cluster-analytic study.

Sought mental illness definitions through the use of the bc try computer system and 1,099 patient records of a modern mental health center. Results of other investigations that had used objective syndrome finding techniques were utilized as the hypotheses, and 8 of 9 predicted syndromes were discovered. Altogether, 11 replicated syndromes appeared. The attempt to relate a set of illness outcome variables to the syndromes, including some variables describing conditions antecedent to hospitalization, was less successful. Findings are discussed in terms of relationships between the syndrome and the feasibility of using record system data for research. (36 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Observations of the treatment of women in the United States with myocardial infarction: a report from the National Registry of Myocardial Infarction-I

BACKGROUND: To determine whether there are sex differences in the demographics, treatment, and outcome of patients with acute myocardial infarction in the United States, data from the National Registry of Myocardial Infarction-I from September 1990 to September 1994 were examined. METHODS: The National Registry of Myocardial Infarction-I is a national observational database consisting of 1234 US hospitals in which each hospital submits data from each patient with acute myocardial infarction to a central data collection center. For these analyses, the following variables were examined in 354 435 patients with acute myocardial infarction: demographics; use of medical therapy including thrombolytic agents; use of procedures including cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery; length of hospital stay; adverse events (stroke, major bleeding, or recurrent myocardial infarction); and causes of death. RESULTS: In comparison with men, women experiencing acute myocardial infarction in the United States are older, with 55.7% older than 70 years. Women have a higher mortality rate than men even when controlled for age and die less often from arrhythmia but more often from cardiac rupture whether or not thrombolytic therapy is used. Treatment with aspirin, heparin, or beta-blockers is less frequent in women. When thrombolytic therapy is used, women are treated an average of almost 14 minutes later than men and experience a greater incidence of major bleeding. Cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery are used less often in women. CONCLUSIONS: Observations from the National Registry of Myocardial Infarction-I document important sex differences in demographics, treatment, and outcome of patients with acute myocardial infarction in the United States.     

National health insurance, psychotherapy, and the poor.

Debate on psychotherapy coverage under national health insurance has centered around perceived inequitable service to different income groups. It has been argued that national health insurance coverage for psychotherapy would represent a subsidy to the affluent by poorer citizens. Four pertinent hypotheses were examined in a series of studies of 5,967 patients in community mental health centers. It has been maintained that the poor would not seek psychotherapy, would receive fewer sessions, would receive either less prestigious treatments or less trained therapists, and would benefit less than the more affluent. None of these hypotheses were supported. The implications of these findings are discussed in terms of psychotherapy coverage under national health insurance and the role of psychologists in a national system of service delivery. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Disomy 1 with terminal 1p deletion is frequent in mass-screening-negative/late-presenting neuroblastomas in young children, but not in mass-screening-positive neuroblastomas in infants

OBJECTIVE: The need for valid and reliable emergency medical services (EMS) data has long been recognized. EMS data are useful for monitoring resources and operations, documenting patient care and outcome, and evaluating injury prevention strategies. The goal of this project was to develop a computerized data set with the capability to generate a patient care record (PCR) to overcome some of the current EMS data limitations. METHODS: The authors discuss developing an electronic PCR and analysis data set containing 233 variables. Data are collected for the following: incident, response, scene, patient, history, primary survey (including vital signs), physical examination, physiologic scores, diagnostics, plan (medications and procedures), assessment, and reevaluation. Software on a portable computer installed in an EMS response unit utilizes a graphical user interface for data collection by prehospital emergency care providers. A data set stores codes corresponding to user's selections. This data set supports data storage and analysis. The electronic PCR and data set can be useful to EMS agencies for collecting, storing, reporting, and analyzing information. RESULTS: Variables are categorized into 12 main categories to categorize the variables and to drive data collection. The system provides the user with the ability to print out a record (using a portable printer installed in an ambulance) and analyze data stored in the data set. CONCLUSION: This computerized approach overcomes many limitations inherent with using paper-based systems for research. Linked with emergency department, hospital discharge, and mortality data, EMS data can be used in systems analyses related to patient outcome.     

Temporal patterns of variable relationships in person-oriented research: Longitudinal models of configural frequency analysis.

This article reviews the premises of configural frequency analysis (CFA), including methods of choosing significance tests and base models, as well as protecting α, and discusses why CFA is a useful approach when conducting longitudinal person-oriented research. CFA operates at the manifest variable level. Longitudinal CFA seeks to identify those temporal patterns that stand out as more frequent (CFA types) or less frequent (CFA antitypes) than expected with reference to a base model. A base model that has been used frequently in CFA applications, prediction CFA, and a new base model, auto-association CFA, are discussed for analysis of cross-classifications of longitudinal data. The former base model takes the associations among predictors and among criteria into account. The latter takes the auto-associations among repeatedly observed variables into account. Application examples of each are given using data from a longitudinal study of domestic violence. It is demonstrated that CFA results are not redundant with results from log-linear modeling or multinomial regression and that, of these approaches, CFA shows particular utility when conducting person-oriented research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The counseling center: A mirror of institutional size.

Investigated the relationship between counseling center orientation and size of institution in which the center is located. 19 census-type variables were subjected to principal components analysis, and 4 estimated factors scores were derived for a population of 157 counseling centers. Results indicate that institutional size predicts counseling center orientation but that a more qualitative evaluation of counseling centers requires other than census-type data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Air pollution and daily mortality in Seoul and Ulsan, Korea

Prenatal diagnosis of chromosomal disorders has been performed for more than 20 years, mainly for advanced maternal age. Chromosomal abnormality rates derived from second trimester amniocentesis have mainly come from a collection of small-scale studies from North America and Western Europe. Accurate risk estimates for chromosomal abnormalities are important tools for the physician or obstetrician who would need to make referrals to a prenatal genetic center. This paper presents amniocentesis rates of clinically significant cytogenetic abnormalities for various indications, including advanced maternal age, previous chromosomal abnormality, parental structural rearrangement and a family history of aneuploidy as defined in the text. These data come from a Canadian prenatal diagnosis laboratory with more than 20 years experience in second trimester cytogenetic analysis. They show that the overall frequency of chromosomal abnormalities for advanced maternal age (> or = 35 years) is 1.79%. In this group, 21% of all abnormalities are structural rearrangements (including markers) and less than half of all abnormalities are trisomy 21. The advanced maternal age specific risk of aneuploidies at second trimester is 1.24%. Recurrence risk for aneuploidy after a previous one is 1.29%. However, it is much higher (4.84%) for women of > or = 35 years. When a parent's brother, sister, nephew or niece is affected, the risk of occurrence of aneuploidies (0.24%) is not elevated. When there is a balanced translocation in one of the parents, the overall risk is 10.2% for unbalanced translocations and 37.3% for balanced translocations.     

On making social research relevant to public policy and national problem solving.

Suggests how social research can become more relevant to governmental efforts to resolve national problems, E.g., poverty. A major function of the research would be to make explicit the goals and beliefs of the several systems donor, delivery, and recipient comprising any national government effort. Data are offered on 1 national effort to train welfare recipients for jobs. Misperceptions between members of the delivery and recipient systems are examined. It is suggested that significant policy research requires (a) a broader framework than usually adopted by a scientific discipline; (b) continuity in the gathering of field data; and (c) a new institutional base that allows scientists and administrators to cooperate in research and policy efforts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Women and school psychology: Professional training, practice, and affiliation.

Considers research concerning women in psychology in general and school psychology in particular, with respect to professional training, professional practice (including its components of employment, research, publications, and editorial activities), and professional affiliation in national organizations. Parallel trends for psychology and school psychology indicate that women are less educated, less visible, and are in the lower academic level of the profession. These trends raise the issue as to whether women have equal access to education and careers in psychology in general and school psychology in particular. Factors involved in these trends are considered. It is concluded that consideration should be given to the multiple forces that reinforce and maintain sex discrimination in academe. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiparasite communities in animals and humans: frequency, structure and pathogenic significance

A separate analysis of ulnar and radial finger ridge-counts, obtained from 115 Aymara Indians (55 males and 60 females) of northern Chile, was performed. From these variables, directional asymmetry, fluctuating asymmetry, indices of bilateral asymmetry (square root of A2), and intraindividual diversity (s/square root of 5) were calculated for each sex. The results show that most bimanual differences for the ridge-counts are not statistically significant in the Aymara, except for radial counts in female first and second fingers (right hand means are larger), while most ulnar-radial differences are highly significant in both sexes (radial values exceed ulnar ones). Most sex differences do not reach statistical significance, although males have more ridge-counts, lower directional asymmetry, somewhat lower fluctuating asymmetry, and lower indices of asymmetry and diversity than females. As fluctuating asymmetry is not larger in males, the dermatoglyphic findings do not indicate support for the hypothesis that males are less canalized than females. In accordance with the findings of other authors, interpopulation comparisons in the indices of asymmetry and diversity show ethnic differences. Both indices tend to be low in samples of African ancestry, high in samples of European origin, and intermediate in the Aymara, while Indian groups are characterized by high asymmetry and low diversity values. Moreover, the data reveal a geographical trend in that asymmetry and diversity values tend to decrease from the northern to the southern hemisphere in populations of Europe, the Middle East, and Africa, thus indicating greater ridge-count variability and heterogeneity among fingers in northern populations. It is assumed that this gradient primarily reflects different degrees of miscegenation and heterozygosity.     

Statistical methods for describing temporal order in longitudinal research

BACKGROUND: Although traditional epidemiological statistical methods (e.g., logistic regression) are useful for describing predictive relationships in longitudinal panel studies in which changes in risk factor levels occur before change in the outcome variable, more sophisticated statistical methods must be used when the temporal order between variables is unknown. METHODS: Using national survey data, the current study shows how log-linear models and discrete-time survival analysis can be used to test for temporal order. The relationship between marijuana use and friends' use of marijuana is examined to illustrate these methods. RESULTS: Using traditional analytic strategies, it appears that friends use and marijuana use are predictive of each other. However, valid tests for temporal order reveal that both variables change concurrently, so there is no temporal order between these variables; rather, these variables tend to change concurrently. CONCLUSION: In many current areas of research, temporal order between theoretically important variables is unknown and traditional analytic strategies will yield misleading results. The fundamental problem with prior approaches is that no estimate of concurrent change is made. Without an estimate of concurrent change, estimates of prediction will be biased. The current study illustrates valid methods that can be used to describe temporal orderings.     

Student responsiveness to specialized college services: Contribution of personality variables and perceptions of services.

Student responsiveness to an offer of vocational assistance from a college counseling center was studied. Vocationally undecided graduating seniors (130 respondents and 145 nonrespondents) were examined on a set of four variables: state anxiety, locus of control, and perceptions of the relevance (measured with items from Warman's Appropriateness Checklist) and of the helpfulness of the Center (measured with items from Form's Counseling Attitude Scale). After invitational letters were mailed, data were collected within a 2?-week period at selected classrooms or in the counseling center. Multiple discriminant analysis and correlational techniques were used to test the relation among variables. As a set, the four variables contributed significantly to the discrimination between respondents and nonrespondents. Examined separately, only perceptions of relevance and of helpfulness were found to be significantly related to responsiveness. Implications for future research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Yes, but what’s the mechanism? (don’t expect an easy answer).

Psychologists increasingly recommend experimental analysis of mediation. This is a step in the right direction because mediation analyses based on nonexperimental data are likely to be biased and because experiments, in principle, provide a sound basis for causal inference. But even experiments cannot overcome certain threats to inference that arise chiefly or exclusively in the context of mediation analysis—threats that have received little attention in psychology. The authors describe 3 of these threats and suggest ways to improve the exposition and design of mediation tests. Their conclusion is that inference about mediators is far more difficult than previous research suggests and is best tackled by an experimental research program that is specifically designed to address the challenges of mediation analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychology on a large scale: The study of consumption.

Suggests that because consumer psychologists customarily deal with large-scale survey data, they are in a position to test hypotheses at a much higher statistical significance and on more representative populations than is common in the small-scale studies which characterize most of the literature in experimental social psychology. Data on personality characteristics now being collected in many large national surveys represent a valuable resource for secondary analysis and a unique opportunity to control for social class and other demographic variables which may be independently related to personality traits. The popularity of personality measures in consumer research has also led to misapplications. Distrust of consumer psychology by many academic psychologists develops because they do not realize its potentially important function in redirecting consumption from individual gratification to the fulfillment of social needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Demographic variables, smoking variables, and outcome across five studies.

Objective: Intervention effectiveness can potentially be affected by membership in different demographic subgroups (race, ethnicity, gender, age, and education level) or smoking behavior variables (time to first cigarette, longest previous quit attempt, number of attempts in the past year, number of cigarettes, and stage of change). Previous research on these 2 sets of variables has produced mixed results. Design: This secondary data analysis combined data from 5 effectiveness trials (a random-digit-dial sample [N = 1,358], members of an HMO [N = 207], parents of students recruited for a school-based study [N = 347], patients from an insurance provider list [N = 535], and employees [N = 175]) in which smokers were all proactively recruited from a defined population and all received the same expert system intervention. The intervention produced a consistent 22% to 26% point prevalence cessation rate across the 5 studies. Main Outcome Measures: The main outcome measures were 24-hr point prevalence, 7-day point prevalence, 30-day prolonged abstinence, and 6-month prolonged abstinence. Results: There were no significant differences in outcome across gender, race, and ethnicity subgroups. There were significant differences and small effect sizes for age and education subgroups. There were significant differences and large effect sizes for all 5 smoking behavior variables. Discussion: Demographic variables are static variables, whereas the smoking variables are more dynamic, that is, open to change. Given the dynamic nature of the smoking variables and the large effect sizes, interventions tailored on the smoking variables should be more successful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Supervising International Students: The Role of Acculturation, Role Ambiguity, and Multicultural Discussions.

Little is known about the training needs of international students in professional psychology programs and what supervisors could do to assist these students in their training. This study surveyed 42 international students in programs accredited by the American Psychological Association concerning several training and supervision variables. Results revealed that students who reported being less acculturated also reported less counseling self-efficacy, weaker supervisory working alliances, more role difficulties in supervision, and more discussion of cultural issues in supervision. Implications for supervision and future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of gonadal steroid hormones on plasma growth hormone concentrations in sexually immature rainbow trout, Oncorhynchus mykiss

Single-cell assays of cell migration, while yielding dynamic measurements of cell position and morphology, are predominantly limited by the time required for data collection and analysis. Computer-aided fluorescence time-lapse videomicroscopy (CAFTiV) was developed in order to facilitate the tracking and rapid examination of large numbers of motile cells. The system combines time-lapse videomicroscopy with epifluorescence capability, which allows full automation of image capture, sorting, and analysis due to the low background in the fluorescence images. Utilizing the CAFTiV system, data analysis time was reduced from over 125 h to less than 1 labor minute. In addition, fluorescence imaging permits cell tracking in small-volume chambers (<100 microL), which is useful should the addition of expensive reagents be required. It is anticipated that the ability to characterize both biochemical and biophysical properties responsible for cell movement will be enhanced by this methodology.     

Machakos project studies. Agents affecting health of mother and child in a rural area of Kenya. XXII. Schistosomiasis transmission in relation to some socio-economic and other environmental factors

A schistosomiasis research project, carried out in part of the Machakos area, yielded data by which it was possible to relate household egg outputs to some socioeconomic and other environmental variables. A significant negative correlation with schistosome scores was found for most variables when tested individually. Multiple regression analysis revealed a relatively strong relation with altitude and a much weaker association with some other variables. It is discussed whether the influence of altitude may be explained by differences in temperature, 'distance from infected water', or both. Furthermore it is hypothesized whether relations with social and economical variables are due to the fact that members of wealthier families stay away from contaminated water more often, have more knowledge of schistosomiasis and differ in hygienic behaviour.     

Phase relation, crystal structure, and magnetic properties of La-Co-Si alloys

OBJECTIVES: To identify ICU-specific predictors of mortality. DESIGN: An inception cohort study. SETTING: Barnes Hospital, an academic tertiary care center. PATIENTS: Consecutive patients, requiring mechanical ventilation, admitted to the medical intensive care unit (ICU) (75 patients), surgical ICU (100 patients), and cardiothoracic ICU (102 patients). INTERVENTIONS: Prospective data collection and outcomes evaluation. MEASUREMENTS AND MAIN RESULTS: Stepwise logistic regression analysis identified the following variables to be independent predictors of mortality for the individual ICUs: medical ICU, an Organ System Failure Index (OSFi) greater than or equal to 3; surgical ICU, OSFI greater than or equal to 3; cardiothoracic ICU, OSFI greater than or equal to 3, requiring acute dialysis, and the occurrence of an iatrogenic event. The same analysis was repeated after removing the OSFI as a potential confounding variable. Independent predictors of mortality identified in this subsequent analysis were as follows: medical ICU, occurrence of renal failure; surgical ICU, supine head positioning, acute physiology score greater than or equal to 10, preadmission lifestyle score greater than or equal to 2; cardiothoracic ICU, requiring acute dialysis, occurrence of ventilator-associated pneumonia, and the occurrence of an iatrogenic event. CONCLUSIONS: We identified the presence of ICU-specific predictors of mortality amongst the three ICUs examined. These data suggest that ICU-specific interventions could be developed to improve the quality of patient care and potentially to reduce patient mortality.