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PsychMate: providing psychology majors the tools to do real experiments and learn empirical methods.

PsychMate is a set of software tools for undergraduate psychology students to run, develop, and analyze computerized experiments. It includes 30 psychological experiments in the areas of perception, cognition, social psychology, human factors, and cognitive neuroscience. Students run experiments themselves and see basic results immediately. The automatic spreadsheet analysis forms allow them to aggregate data and create analyses, presentations, and Web pages with a single click. Students can use the Psychology Experiment Authoring Kit experiment editor to create their own experiments in minutes and run experiments with other students using Web-based experiment-management tools. The BrainTutor and BrainViewer applications teach brain anatomy and permit students to analyze fMRI brain imaging data from subjects who have performed the same memory experiments in which they participated. PsychMate has been used in 83 classes in which 1,533 students submitted 5,464 completed experiments with few (less than 1%) requests for help and a very positive rating of the research experience.

Brain↗

Relative consistency and subjects' "theories" in domains such as naive physics: common research difficulties illustrated by Cooke and Breedin.

While augmenting the literature with data that further exhibit context-specific responding to qualitative motion problems, Cooke and Breedin (1994) exhibit common theoretical and methodological difficulties that undermine their conclusions. Herein, these flaws are explicated and contrasted with features of studies that avoid the pitfalls of (1) theoretical vagueness, (2) overly coarse data aggregation, (3) nondiagnostic, errorful assessment items, and (4) imprecise measures of the variety of (mis/)conceptions (e.g., of "impetus," or inertia). The difficulties call into question Cooke and Breedin's claims that impetus ideas play minor roles in performance and that "naive theories" of motion are largely constructed on line. Because such confusion often arises from the polysemy of "theory," some empirical criteria for "theoryness" are discussed, including subjects' conceptual, temporal, and coherence-based consistencies (regarding researchers' models and isomorphs). While naive physics may be idiosyncratic, baroque, context-driven, and apparently inconsistent, it might (additionally) be based upon fairly a priori, systematic, and temporally stable information.

Concept Formation↗

Predicting conjunction typicalities by component typicalities.

In two studies, we investigated to what extent typicalities in conjunctive concepts phrased as relative clauses--such as pets that are also birds--can be predicted from simple functions of constituent typicalities and from extensions of such functions. In a first study, analyses of a large aggregated data set, based on seven different experiments, showed that a calibrated minimum rule model and some extensions of this model accounted for a very large part of the variance in the conjunction typicalities. The same models can also account for the so-called guppy effect. A psychological explanation is presented, which states that typicalities in contrast categories, like pets that are not birds and birds that are not pets, further improve the prediction of conjunction typicalities. This hypothesis is tested in a second study.

Adult↗

Multistate worklife expectancies.

This communication reviews the demographic concept of worklife expectancy and draws the epidemiologists' attention to its usefulness in occupational health research and pension policy making. The distinctions between different analytic approaches to the quantification of expected workforce status and mobility are pointed out. A recently developed multivariate large-sample regression method for the analysis of worklife tables is placed into the general context of life tables. Given aggregated data from multiple cross-sectional or longitudinal population surveys, a multistate regression model can be used to estimate consistently marginal probabilities that a person is in a given work-health state or transition probabilities between the states and, thereby, worklife expectancies. The methodology is illustrated through the application to data from Finnish population statistics on employment, disability, retirement, and mortality. The paper closes with a discussion of the methodological issues and empirical findings on pension policy in Finland.

Finland↗

Utilization and costs of home-based and community-based care within a social HMO: trends over an 18-year period.

PURPOSE: Our objective was to describe the utilization and costs of services from 1985 to 2002 of a Social Health Maintenance Organization (SHMO) demonstration project providing a benefit for home-based and community-based as well as short-term institutional (HCB) care at Kaiser Permanente Northwest (KPNW), serving the Portland, Oregon area. The HCB care benefit was offered by KPNW as a supplement to Medicare's acute care medical benefits, which KPNW provides in an HMO model. KPNW receives a monthly per capita payment from Medicare to provide medical benefits, and Medicare beneficiaries who choose to join pay a supplemental premium that covers prescription drugs, HCB care benefits, and other services. A HCB care benefit of up to 12,000 dollars per year in services was available to SHMO members meeting requirement for nursing home certification (NHC). METHODS: We used aggregate data to track temporal changes in the period 1985 to 2002 on member eligibility, enrollment in HCB care plans, age, service utilization and co-payments. Trends in the overall costs and financing of the HCB care benefit were extracted from quarterly reports, management data, and finance data. RESULTS: During the time period, 14,815 members enrolled in the SHMO and membership averaged 4,531. The proportion of SHMO members aged 85 or older grew from 12 to 25%; proportion meeting requirements for NHC rose from 4 to 27%; and proportion with HCB care plans rose from 4 to 18%. Costs for the HCB care benefit rose from 21 dollars per SHMO member per month in 1985 to 95 dollars in 2002. The HCB care costs were equivalent to 12% to 16% of Medicare reimbursement. The HCB program costs were covered by member premiums (which rose from 49 dollars to 180 dollars) and co-payments from members with care plans. Over the 18-year period, spending shifted from nursing homes to a range of community services, e.g. personal care, homemaking, member reimbursement, lifeline, equipment, transportation, shift care, home nursing, adult day care, respite care, and dentures. Rising costs per month per SHMO member reflected increasing HCB eligibility rather than costs per member with HCB care, which actually fell from 6,164 dollars in 1989 to 4,328 dollars in 2002. Care management accounted for about one-quarter of community care costs since 1992. CONCLUSIONS: The Kaiser Permanente Northwest SHMO served an increasingly aged and disabled membership by reducing costs per HCB member care plan and shifting utilization to a broad range of community care services. Supported by a disability-based Medicare payment formula and by SHMO beneficiaries willing to pay increasing premiums, KPNW has been able to offer comprehensive community care. The model could be replicated by other HMOs with the support of favorable federal policies.

Journal Article↗

The role of N-acetylcysteine in preventing radiographic contrast-induced nephropathy.

INTRODUCTION: There have been many small randomized controlled trials evaluating the effectiveness of N-acetylcysteine (NAC) in preventing radiographic contrast-induced nephropathy. Most studies have suggested a beneficial NAC effect. This meta-analysis describes the effect of NAC in the prevention of radiographic contrast-induced nephropathy in the aggregated trial data. METHODS: A search using MEDLINE from 1966 to December 2003 identified all randomized control trials that evaluated NAC in those patients at risk of acute renal failure (ARF) following either angiographic or CT scan contrast exposure. All studies included in the review employed the use of either low-osmolar (n = 9 trials) or iso-osmolar (n = 2 trials) contrast agents. The outcome of interest was ARF as defined by a rise in serum creatinine (Cr > or = 0.5 mg/dl rise or > 25% increase from baseline) after exposure to contrast. The data were aggregated by the methods of Mantel and Haenszel. RESULTS: The overall summary odds ratio estimate of 0.46 (95% confidence interval 0.32 - 0.66) suggests a strong protective effect of NAC in preventing radiographic-induced nephropathy. CONCLUSION: In summary, there is good aggregate trial evidence to suggest that patients who have an elevated serum creatinine level at baseline benefit from receiving periprocedure NAC in the prevention of contrast-induced ARF.

Acetylcysteine↗

Jobless. Unemployment and young people's health.

Morrell, Taylor and Kerr, from the University of Sydney's Department of Public Health, review the evidence of an association between unemployment and psychological and physical ill-health in young people aged 15-24 years. Aggregate data show youth unemployment and youth suicide to be strongly associated. Youth unemployment is also associated with psychological symptoms, such as depression and loss of confidence. Effects on physical health have been less extensively studies; however, there is some evidence for an association with raised blood pressure. Finally, the prevalence of lifestyle risk factors (cannabis use and, less consistently, tobacco and alcohol consumption) is higher in unemployed compared with employed young people.

Adolescent↗

Residential aged care and general practice: workforce demographic trends, 1984-2000.

OBJECTIVE: To examine the demographic changes in the cohort of general practitioners servicing residential aged-care facilities (RACFs) from 1984 to 2000. DESIGN: Quantitative analysis of Medicare datasets from 1984 to 2000. PARTICIPANTS AND SETTING: All GPs who provided Medicare-claimed RACF services from 1984 to 2000. MAIN OUTCOME MEASURES: Aggregate data on RACF GPs by age group and sex; total and average number of RACF services by GP age group and sex. RESULTS: The proportion of RACF GPs younger than 35 years has declined from a peak of 30.2% in 1986 to 11.5% in 2000. GPs aged 45 years and older made up 58.1% of all RACF GPs in 2000, compared with 41.4% in 1984. In 2000, 28.4% of RACF GPs were female, compared with 13.5% in 1984. The proportion of RACF services provided by GPs younger than 35 years fell from 19.2% in 1984 to 4.5% in 2000, and the proportion provided by GPs aged 45 years and older increased from 54.7% to 72.4%. Female GPs' RACF services as a proportion of all RACF services increased from 8.9% to 15.9% between 1984 and 2000, but the average number of RACF services per female GP declined by 15.6 services per year. In contrast, the average number of RACF services per male GP increased by 11.2 per year. The increasing rate of RACF servicing by older GPs is independent of female GPs' declining involvement. CONCLUSION: Our results suggest an increasing reliance on older, male GPs in the supply of RACF services. Although the proportion of female RACF GPs has increased, average services by these GPs, who are generally younger, has declined. The personal and work preferences of female GPs may have implications for future RACF services supply as older, generally male, GPs retire.

Adult↗

Recognising adverse events and critical incidents in medical practice in a district general hospital.

A pilot audit of case records of consecutively discharged patients from a district general hospital was undertaken by specialist registrars, SHOs and senior nurses in order to identify adverse events (AEs) and critical incidents (CIs) related to hospital care. Experienced external assessors taught the clinical staff to use a previously validated structured method of case record review that facilitates analysis. The external assessors audited the same case records in parallel. Aggregated data from 154 case records of patients admitted to the general medical wards were collected for analysis. Fifteen AEs and 41 CIs were identified in the case records covering the hospital admission. In addition, 16 AEs and nine CIs were discovered to have occurred before admission or, for three AEs, shortly after discharge. One-half of the episodes related to problems arising during ward care and for one-half of these issues remained unresolved at the time of discharge. One-third of episodes related to medications or the administration of intravenous fluids--and in these cases there were defects in monitoring the patients' clinical progress. This study led to initiatives to improve care at the host hospital and we believe that further programmes along similar lines are indicated.

Adult↗

Determination of fees by professionals: an exploratory investigation of dentists.

Previous research has attempted to infer dentists' pricing practices from aggregate data, such as those derived from insurance claims. In a disaggregated analysis based on a mail survey of 327 dentists in private practice, the authors find the most important influence on dental fees to be cost, followed by fees charged by other dentists and perceptions of patient sensitivity to prices. The relative importance of the various influences on dentists' fees is related to several practice characteristics, including location and gross income.

Chi-Square Distribution↗

Clinical practice guidelines. The Agency for Health Care Policy and Research fosters the development of evidence-based guidelines.

As medical technology increases rapidly and becomes more complex, clinical practice guidelines can help healthcare providers assess current practices and integrate technological advances. Through the Agency for Health Care Policy and Research (AHCPR), the federal government has begun to facilitate the development of clinical practice guidelines. Expert or contract panels, authorized by the AHCPR, develop guidelines on specific clinical conditions. The AHCPR guideline methodology is designed to produce evidence-based guidelines that are valid, clinically applicable, and clinically flexible. Each panel spends a year or more developing the guideline, beginning with an extensive literature search and review. The panel prepares evidence tables, statistically analyzes aggregate data (where appropriate), conducts harm and benefit analyses, and prepares health policy analyses (or cost-impact studies). During this process, the panel holds an open forum to solicit comments on the guideline topic. After this public discussion, the panel prepares a final draft of the guideline. Several hundred individuals review the guideline. Some policymakers believe clinical practice guidelines can lead to better healthcare outcomes. Guidelines can provide information in a useful format for clinicians to use at the bedside or the point of decision making in patient care. Guidelines also provide information that can be used in continuing education and professional education programs.

Decision Making↗

Mental health services within the HMO group.

This paper describes the organizational characteristics, benefits, referral, utilization, and costs of mental health services within 17 health maintenance organization (HMOs) comprising The HMO Group in 1990. All 17 health plans responded to the questionnaire, resulting in a 100% response rate. Responses to the survey reflected the complexity of the HMO mental health services field. Overall, The HMO Group members provided mental health service coverage, partly dependent upon state mandates, employer group priorities, and local competitive benefit structures. HMOs reported that service utilization rates and the productivity of their mental health providers were critical information needs. Overall, the responses reflected the need for continued information sharing between The HMO Group members, the modification of management information systems, and continuation of establishing a mental health aggregate data base.

Data Collection↗

Unravelling the confusion caused by GASB, FASB accounting rules.

Separate GASB and FASB accounting and financial reporting rules for governmental healthcare providers are producing confusion. Among other problems, they reduce the usefulness of aggregated data about the healthcare industry. This article addresses the inconsistencies of the various reporting standards and identified problems they can cause.

Accounting↗

Factors that may explain interstate differences in certificate-of-need decisions.

A major difficulty in conducting studies of the impact of certificate-of-need programs is in accounting for interstate differences in program characteristics. This paper addresses this problem by examining the empirical relationship between various characteristics of certificate-of-need programs and program decisions, measured in terms of the approvals of hospital capital projects. Aggregate data on capital expenditure approvals and net bed change approvals for 28 States are correlated with an index of each State's regulatory characteristics that was developed in an earlier study. In addition, a multivariate model of certificate-of-need approvals is estimated in which certain measures associated with the need for hospital capital in a State are introduced, along with the indices of regulatory characteristics, to explain interstate differences in regulatory characteristics, to explain interstate differences in program decisions. The results of this analysis indicate that although regulatory characteristics are significantly correlated with the relative number of new beds approved, they have little correlation with total capital expenditure approvals. Moreover, variables reflecting the need for new hospital capital in a State, such as past population growth and existing hospital capacity, appear to be more important than regulatory characteristics in explaining the relative amount of capital approvals.

Capital Expenditures↗

The cost of tuberculosis: utilization and estimated charges for the diagnosis and treatment of tuberculosis in a public health system.

SETTING: An urban tuberculosis (TB) control program. OBJECTIVE: The use of medical services was analyzed from diagnosis through completion of treatment for TB patients in a public health system in order to estimate charges and service utilization. DESIGN: The in- and out-patient medical records, including long term care and jail health service records, were retrospectively reviewed for the first 100 patients diagnosed with TB in 1993 at a public hospital. Because the hospital did not have a cost-accounting system, charges were estimated based on a variety of sources. RESULTS: Complete records were available for 92 patients; one outlier was excluded. The resulting 91 patients represented 11% of newly diagnosed patients in Chicago in 1993. Overall, almost 99% of the charges reflected in-patient (acute and long term care) utilization. Total charges of $3,154,583 represent the charges to complete therapy for only 46 patients, or $68,578 per completed case. CONCLUSIONS: This study attempts to overcome the limitations of aggregate data sets by looking at individual patients followed longitudinally through a complex public health system. Expensive in-patient care may be partially, but not completely, replaced by directly observed therapy. The findings may be used to predict resource utilization for diagnosis and treatment programs.

Adult↗

Methodologic issues in epidemiologic risk assessment.

This paper reviews methodologic issues pertinent to the application of epidemiology in risk assessment and discusses concerns in the presentation of results from such an activity. Assessment of the health risks associated with occupational and environmental exposures involves four phases: hazard identification, i.e., the detection of the potential for agents to cause adverse health effects in exposed populations; exposure assessment, i.e., the quantification of exposures and the estimation of the characteristics and sizes of the exposed populations; dose-response assessment, i.e., the modeling for risk realization; and risk characterization, i.e., the evaluation of the impact of a change in exposure levels on public health effects. The risk-assessment process involves limitations of exposure data, many assumptions, and subjective choices that need to be considered when using this approach to provide guidance for health policy or action. In view of these uncertainties, we suggest that the provision of estimates of individual risk and disease burden in a population must be accompanied by the corresponding estimates of precision; risks should be presented in a sufficiently disaggregated form so that population heterogeneities are not lost in the data aggregation; and different scenarios and risk models should be applied. The methods are illustrated by an assessment on the health impacts of exposure to silica.

Decision Support Techniques↗

Bivariate analysis of surgically induced regular astigmatism. Mathematical analysis and graphical display.

OBJECTIVE: The purpose of the study was to develop methods for simultaneous description of astigmatic direction and magnitude on aggregate data, with special reference to refractive surgery. DESIGN: Mathematical analysis of astigmatisms employing bivariate statistical methods. RESULTS: The mean of several astigmatisms is a new astigmatism of specific direction and magnitude, while the confidence region is an area, which may be determined exactly. CONCLUSIONS: Astigmatisms may conveniently be symbolized as an astigmatic direction and magnitude, but are actually composed of refractive powers in the form of polar values. We are operating with two different entities, a net astigmatism and a power vector in the form of polar values. There is an unequivocal point-to-point correlation between these entities. Mathematical conversions can only be performed with polar values, but never by using net astigmatisms. All net astigmatisms must be converted to their appropriate refractive powers and the relevant calculations performed with these entities. The final result, such as an average of several astigmatisms, variances or confidence areas, may be point-to-point reconverted to and symbolized by a net astigmatism. These principles allow for exact description and comparison of surgical methods, but may be employed to describe and analyze any other population of astigmatisms, such as subjective cylinders and spectacle corrections.

Astigmatism↗

Dietary fiber and breast cancer.

The Fiber Hypothesis which had its origins in the work of Burkitt and others in the early 1970's, focussed largely on fiber's beneficial effects on colon cancer and disorders of the gastric intestinal tract. In the 1980's it was proposed that fiber may also have beneficial effects on breast cancer and a rational for this was proposed involving modulation, by fiber, of the enterohepatic recirculation of estrogens. In the following the evidence from epidemiology, clinical interventions and animal model studies, supporting a role for fiber in breast cancer is critically reviewed. Evidence from animal model studies support the notion that supplementary fiber inhibits chemically-induced mammary tumorigenesis but do not support an estrogen-based mechanism. Some studies in human populations suggest modulation by estrogens and some do not. The aggregate data point to minor constituents present in fiber, such as isoflavones and phytate as the biologically active components of fiber which may be responsible for its anti cancer effects.

Animals↗