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PubMed2003

Current situation and regional perspective on HIV/AIDS surveillance in europe.

AIDS reporting has been the principal means of monitoring the HIV/AIDS situation in Europe since 1984 [corrected]. HIV reporting was set up at the European level in 1999, although it has existed in most European countries since the 1980s. Anonymous individual data on AIDS and, if available, new HIV diagnoses, and data on HIV prevalence in various populations are reported from the 51 countries of the WHO European Region to EuroHIV, and aggregate data on HIV prevalence in various populations [corrected]. Data are presented after grouping the 51 countries into three geographic areas: the West, Center, and East. At end of 2000, in the West, AIDS incidence continued to decline except among those infected heterosexually; numbers of newly diagnosed HIV infections are relatively stable, but rising among heterosexually infected persons, many of whom originate from countries with generalized HIV epidemics. In the East, numbers of newly diagnosed HIV cases (mostly injection drug users) continue to rise steeply, particularly in the Russian Federation, Latvia, and Estonia. In the Center, levels of HIV and AIDS remain low. HIV reporting is becoming a central element of HIV/AIDS surveillance in Europe. Heterogeneity between countries in health care systems, HIV testing patterns and surveillance systems remain challenging for data standardization at the European level. Efforts should be made to use surveillance data for evaluating the effectiveness of HIV/AIDS prevention interventions.

Adolescent↗
PubMed1997

Principles of signal detection in pharmacovigilance.

Adverse drug effects are manifold and heterogenous. Many situations may hamper the signalling (i.e. the detection of early warning signs) of adverse effects and new signals often differ from previous experiences. Signals have qualitative and quantitative aspects. Different categories of adverse effects need different methods for detection. Current pharmacovigilance is predominantly based on spontaneous reporting and is mainly helpful in detecting type B effects (those effects that are often allergic or idiosyncratic reactions, characteristically occurring in only a minority of patients and usually unrelated to dosage and that are serious, unexpected and unpredictable) and unusual type A effects (those effects that are related to the pharmacological effects of the drug and are dosage-related). Examples of other sources of signals are prescription event monitoring, large automated data resources on morbidity and drug use (including record linkage), case-control surveillance and follow-up studies. Type C effects (those effects related to an increased frequency of 'spontaneous' disease) are difficult to study, however, and continue to pose a pharmacoepidemiological challenge. Seven basic considerations can be identified that determine the evidence contained in a signal: quantitative strength of the association, consistency of the data, exposure response relationship, biological plausibility, experimental findings, possible analogies and the nature and quality of the data. A proposal is made for a standard signal management procedure at pharmacovigilance centres, including the following steps: signal delineation, literature search, preliminary inventory of data, collection of additional information, consultation with the World Health Organization Centre for International Drug Monitoring and the relevant drug companies, aggregated data assessment and a report in writing. A better understanding of the conditions and mechanisms involved in the detection of adverse drug effects may further improve strategies for pharmacovigilance.

Adverse Drug Reaction Reporting Systems↗
PubMed1981

Use of active patient follow-up in cancer registries for designing epidemiologic studies.

The two primary functions of a population-based cancer registry are to collect incidence data and survival data, often obtained by active contact methods. Because of the expense and complexities of epidemiological research in determining carcinogenic risk, existing aggregate data collection systems need to be utilized for generating hypotheses. Direct follow-up contact with a patient by mail provides a mechanism for identifying potential risk factors at low cost. This method is being used to solicit information concerning environmental exposure. In addition, analysis of preliminary data on education and occupation collected by the mechanism indicated that staying patterns of cancer differ between rural and urban areas in the state of Iowa. The difference appears to be explained by education and not by occupation.

Follow-Up Studies↗
PubMed2005

Using software agents to preserve individual health data confidentiality in micro-scale geographical analyses.

Confidentiality constraints often preclude the release of disaggregate data about individuals, which limits the types and accuracy of the results of geographical health analyses that could be done. Access to individually geocoded (disaggregate) data often involves lengthy and cumbersome procedures through review boards and committees for approval (and sometimes is not possible). Moreover, current data confidentiality-preserving solutions compatible with fine-level spatial analyses either lack flexibility or yield less than optimal results (because of confidentiality-preserving changes they introduce to disaggregate data), or both. In this paper, we present a simulation case study to illustrate how some analyses cannot be (or will suffer if) done on aggregate data. We then quickly review some existing data confidentiality-preserving techniques, and move on to explore a solution based on software agents with the potential of providing flexible, controlled (software-only) access to unmodified confidential disaggregate data and returning only results that do not expose any person-identifiable details. The solution is thus appropriate for micro-scale geographical analyses where no person-identifiable details are required in the final results (i.e., only aggregate results are needed). Our proposed software agent technique also enables post-coordinated analyses to be designed and carried out on the confidential database(s), as needed, compared to a more conventional solution based on the Web Services model that would only support a rigid, pre-coordinated (pre-determined) and rather limited set of analyses. The paper also provides an exploratory discussion of mobility, security, and trust issues associated with software agents, as well as possible directions/solutions to address these issues, including the use of virtual organizations. Successful partnerships between stakeholder organizations, proper collaboration agreements, clear policies, and unambiguous interpretations of laws and regulations are also much needed to support and ensure the success of any technological solution.

Computer Security↗
PubMed2006

Linkage of survey data with district-level lung cancer registrations: a method of bias reduction in ecological studies.

OBJECTIVE: To investigate a stratified ecological method for reducing ecological bias in studies that use aggregate data, by incorporating information on individual-level risk factors into the analysis. DESIGN: Cross-sectional study investigating associations between socioeconomic risk factors and lung cancer in the north of England, using 1991 UK Census Small Area Statistics and Sample of Anonymised Records with lung cancer registrations from three regional cancer registries for 1993-6. SETTING AND PATIENTS: 92 local authority districts in the north of England containing over three million people aged 45-74 years. RESULTS: Generally, groups considered more socioeconomically disadvantaged had an increased risk of lung cancer across districts. In the standard ecological analysis, effects for non-car ownership, social class III manual, social class IV/V and socioeconomic inactivity were insignificant, suggesting ecological bias. In the stratified ecological analysis these effects became significant (rate ratio (RR) 2.23, 95% confidence interval (CI) 1.79 to 2.78, p<0.001; RR 1.35, 95% CI 1.04 to 1.74, p = 0.022; RR 2.36, 95% CI 1.86 to 2.99, p<0.001; and RR 0.72, 95% CI 0.53 to 0.98, p = 0.039, respectively), and spuriously large positive effects for the social class III non-manual (RR 20.29) and unemployment groups (RR 147.53) reduced to a more reasonable level (RR 1.92, 95% CI 1.46 to 2.52, p<0.001; and RR 2.36, 95% CI 1.22 to 4.55, p = 0.011, respectively). CONCLUSIONS: Stratified ecological analysis incorporating information on individual-level covariates reduced the bias seen in a standard ecological analysis. The method is straightforward to apply and allows the linkage of health data with data from any large-scale complex survey where district of residence is known.

Adult↗
PubMed1997

Demystifying mental health information needs through integrated definition (IDEF) activity and data modeling.

Today, the process of mental health assessments and treatment are difficult to describe and assimilate into other medical areas. Integrated patient summaries and treatment descriptions are poorly standardized. Any aggregate data analysis must rely on the very few standardized patient data points that may include some demographic information, diagnosis and codable procedures. This paper describes one of the first published attempts to use business process reengineering (BPR) Integrated Computer Assisted Manufacturing Definition (IDEF) activity and data modeling within a focused clinical setting. The clinician's desire to focus on patient care has been used to create both a current and an idealized activity and data model. Clinical patient information was used to build an analyzable database. This provides the potential to track a patient in data throughout a continuum of care. Conceptually, outcomes management is able to use clinical, rather than administrative or claims, data. These models were used to create a prototype for a computer-based patient record which would allow outcomes management. It was tested successfully as a proof of concept.

Ambulatory Care Information Systems↗
PubMed2006

Meta-analysis supports association between serotonin transporter (5-HTT) and suicidal behavior.

Suicidal behavior, which ranks among the top 10 causes of death worldwide, is an important public-health problem and a psychiatric disorder, which has been the subject of considerable study. Studies have shown association between the serotonin transporter (5-HTT) gene and suicidal behavior, although a proportion of alternative studies have produced contrary results both in terms of positive and negative findings, possibly reflecting inadequate statistical power and the use of different populations. Using the cumulative data from recent years in both European and, more particularly, Asian populations, this updated meta-analysis seeks to examine whether the aggregate data provide evidence of statistical significance, and to clarify the contradictory findings suggested by previous studies. It covers all published studies using multiple research methods up to January 2006. Compared with a previous meta-analysis, which found no association between the 5-HTTLPR polymorphism and suicidal behavior (P=0.38), the current results (39 studies) suggest a significant association with a P-value of 0.0068 (overall odds ratio=0.88 (0.8,0.97)), and supports the involvement of the brain 5-HTT in the pathogenesis of suicidal behavior.

Depressive Disorder↗
PubMed2002

Hydrogen/deuterium exchange and aggregation of a polyvaline and a polyleucine alpha-helix investigated by matrix-assisted laser desorption ionization mass spectrometry.

The membrane-associated pulmonary surfactant protein C (SP-C), containing a polyvaline alpha-helix, and a synthetic SP-C analogue with a polyleucine helix (SP-C(Leu)) were studied by hydrogen/deuterium exchange matrix-assisted laser desorption ionization (MALDI) mass spectrometry. SP-C, but not SP-C(Leu), formed abundant amyloid fibrils under experimental conditions. In CD(3)OD/D(2)O, 91:9 (v/v), containing 2 mM ammonium acetate, SP-C(Leu) and SP-C exchanged 40% of their exchangeable hydrogens within 1 min. This corresponds to exchange of labile side-chain hydrogen atoms, hydrogens on the N- and C-terminal heteroatoms, and amide hydrogen atoms in the unstructured N-terminal regions. After approximately 300 h, four exchangeable hydrogen atoms in SP-C(Leu) and 10 in SP-C remained unexchanged. During this time period the ion current corresponding to singly charged SP-C decreased to <10% of the initial value due to the formation of insoluble aggregates that are not detected by MALDI mass spectrometry. In contrast, the ion current for SP-C(Leu) was maintained over this time period, although the peptides were incubated together. In combination, hydrogen/deuterium exchange and aggregation data indicate that the polyleucine peptide refolds into a helix after opening, while the unfolded polyvaline peptide forms insoluble beta-sheet aggregates rather than refolding into a helix. The SP-C helix, but not the SP-C(Leu) helix, is thus in a metastable state, which may contribute to the recently observed tendency of SP-C and its precursor to misfold and aggregate in vivo.

Animals↗
PubMed1982

Privacy Act; notification of a new system of records. Public Health Service. Notification of a new system of records: 09-30-0039, "Drug Abuse Treatment Outcome Prospective Study (TOPS)".

In accordance with the requirements of the Privacy Act, the Public Health Service (PHS) is publishing a notice of a new system of records entitled "Drug Abuse Treatment Outcome Prospective Study (TOPS," HHS/ADAMHA/NIDA, in the Alcohol, Drug Abuse, and Mental Health Administration (ADAMHA), National Institute on Drug Abuse (NIDA). We are also proposing routine uses for this system of records. The purpose of the system is to compile information (data base) for a long-term, large-scale followup study of clients entering drug abuse treatment programs. NIDA will analyze aggregate data to assess the effectiveness of drug abuse treatment programs and to obtain data on drug abusers' behavior and characteristics subsequent to their contacts with the programs.

Confidentiality↗
PubMed2001

Astigmatism analysis by the Alpins method.

PURPOSE: To determine the effectiveness of correcting astigmatism by laser refractive surgery by a vectorial astigmatism outcome analysis that uses 3 fundamental vectors: target induced astigmatism vector (TIA), surgically induced astigmatism vector, and difference vector, as described by the Alpins method. METHODS: A data set of 100 eyes that had laser in situ keratomileusis to correct myopia and astigmatism (minimum preoperative refractive astigmatism 0.75 diopter) was analyzed. The data included preoperative and 3 month postoperative values for manifest refraction and standard keratometry. Using the ASSORT or VectrAK analysis program, individual and aggregate data analyses were performed using simple, polar, and vector analysis of astigmatism and an analysis of spherical change. Statistical analysis of the results was used for means and confidence limits, as well as to examine the differences between corneal and refractive astigmatism outcomes. RESULTS: At an individual patient level, the angle of error was found to be significant, suggesting variable factors at work, such as healing or alignment. A systematic error of undercorrection of astigmatism is prevalent in the treatment of these 100 patients by a factor of between 15% and 30%, depending on whether refractive or corneal values are examined. Spherical correction showed systematic undercorrection of 11%, and parallel indices demonstrated it to be more effective than the astigmatic correction. CONCLUSION: This method of astigmatism analysis enables the examination of results of astigmatism treatment measured by both refractive and corneal measurements using vector analysis. By examining individual vector relationships to the TIA (ie, the correction index, index of success, and flattening index), a comprehensive astigmatism analysis is completed. Each index provides information necessary for understanding any astigmatic change. Astigmatic outcome parameters are more favorable when measured by subjective refractive than objective corneal methods.

Astigmatism↗
PubMed2005

Reanalysis and perspective in the heat--aggression debate.

B. J. Bushman, M. C. Wang, and C. A. Anderson argued that a reanalysis of E. G. Cohn and J. Rotton's Minneapolis data shows no inverted-U curvilinear relationship between temperature and aggression. Although B. J. Bushman et al.'s claim of no general inverted-U trend in the data might well be supported statistically, more careful examination of the subset of the data most likely to include the hottest temperatures in the study may offer at least some support for the inverted-U relationship. Aggregating data to describe a general trend minimizes the influence of outliers that may reflect alternative relationships, and such alternatives may be important practically and theoretically.

Aggression↗
PubMedDate not supplied

Children in Illinois with elevated blood lead levels, 1993-1998, and lead-related pediatric hospital admissions in Illinois, 1993-1997.

OBJECTIVE: This study uses screening and hospitalization data to describe the prevalence of childhood lead poisoning in Chicago and the rest of the state of Illinois. METHODS: The authors used aggregate data published by the Illinois Department of Public Health on blood lead testing of children ages 0-6 years and data on lead-related hospital admissions of children ages 0-6 years, drawn from an administrative dataset compiled as part of a state initiative. RESULTS: No clear time trends in the percentage of children with elevated blood lead levels (defined as >15 micrograms per deciliter [microg/dL] or >45 microg/dL) were evident in either Chicago or the rest of Illinois. The proportions of children with elevated blood lead levels in Chicago and in the rest of Illinois did not decline at the dramatic rate seen in the US as a whole during the 1990s. Over a five-year period, in-hospital charges of $7.7 million were generated for the care of lead-poisoned children ages 6-16 in Chicago alone. CONCLUSION: Surveillance data, analyzed at the appropriate geographic level, can be used to focus resources on high-risk areas and to evaluate prevention efforts.

Chicago↗
PubMed2005

Adolescent use of the combined oral contraceptive pill: a retrospective observational study.

AIMS: To determine the extent of combined oral contraceptive use by girls aged 10-16 years in Scotland. METHODS: Assessment of combined oral contraceptive prescribing in 35 414 girls for the year 1 November 1999-31 October 2000 from data retrieved from 161 primary care practices taking part in the Scottish Programme for Improving Clinical Effectiveness in Primary Care, and from national aggregated data from family planning clinics. RESULTS: During the study period the oral contraceptive pill (OCP) was prescribed by a primary care physician to 1531 girls (4.3%) aged 10-16 years. The age specific prevalence rates per 1000 girls registered with their family doctor rose from 0.9/1000 girls aged 12 years or younger, to 6.9, 30, 86.3, and 174.8/1000 for girls aged 13, 14, 15, and 16 years respectively. The overall prevalence of combined oral contraceptive prescribing by primary care physicians was 43.2/1000 girls aged 10-16 years. A further 1765 girls aged 13-16 years obtained a prescription for the OCP from a Scottish family planning clinic, giving an overall prevalence rate for family planning clinic prescribing of 8.0/1000 girls aged 10-16 years. Despite reportedly high levels of sexual activity and teenage pregnancy in this age group, these results confirm that OCP use is relatively low. CONCLUSIONS: The UK has the highest rate of teenage pregnancy in Western Europe, but despite the medical and social concerns about the sexual health of teenagers, the level of oral contraceptive use in this young age group remains low.

Adolescent↗
PubMed2000

Early detection of preeclampsia by determination of platelet aggregability.

Preeclampsia is still a leading cause of maternal and fetal morbidity and mortality. There is evidence for the involvement of platelets. Therefore, we investigated the suitability of corrected whole blood impedance aggregometry as an early predictor of preeclampsia in 71 consecutive, high-risk pregnancies. According to the occurrence of preeclampsia, defined postpartum by an independent investigator, and the stage of pregnancy (early and late, cutoff: 25 weeks of gestation), four study groups were defined. Platelet aggregation data were corrected for the influence of hematocrit and platelet count by a special purpose software package. Women developing preeclampsia showed significantly higher platelet aggregation response compared to controls in early and late pregnancy. In early pregnancy, all women developing preeclampsia had aggregation responses to collagen higher than the highest responses among the controls. Hence, this test had a 100% positive predictive value of subsequent preeclampsia. Despite being significantly increased, platelet aggregability was of minor predictive value in late pregnancy. We conclude that preeclampsia is accompanied by exaggerated platelet aggregability, particularly perceptible early in the course of pregnancy. We propose collagen-induced whole blood platelet aggregation with correction for the influence of hematocrit and platelet count for early detection of preeclampsia.

Adenosine Diphosphate↗
PubMed2005

Antidepressant drug use and suicide prevention.

Depression has been identified as occurring in the majority of people who commit suicide. Effective antidepressant medications have been available for over half a century. It seems logical to conclude that treatment of depression with antidepressants would have a suicide preventive effect. This has been difficult to demonstrate due to the infrequency of suicide and methodological problems in prospectively testing the hypothesis. Pooled data from controlled clinical trials of antidepressants have not demonstrated a suicide preventive effect, but patient selection and the brief time of most trials limits the power of the data. Some reports from either long-term or very large databases have provided evidence that antidepressants prevent suicide. All but one study using aggregated data from naturalistic settings have shown inverse relationships between use of antidepressants and suicide rates in various populations. Definite conclusions cannot be drawn from naturalistic studies since unknown confounders cannot be excluded. The number of geographically widespread studies reporting positive results with varying methods leads us to conclude, however, that antidepressants do exert a suicide preventive effect.

Antidepressive Agents↗
PubMed1999

Crystalloids vs. colloids in fluid resuscitation: a systematic review.

OBJECTIVE: To systematically review the effects of isotonic crystalloids compared with colloids in fluid resuscitation. DATA SOURCES: Computerized bibliographic search of published research and citation review of relevant articles. STUDY SELECTION: All randomized clinical trials of adult patients requiring fluid resuscitation comparing isotonic crystalloids vs. colloids were included. Pulmonary edema, mortality, and length of stay were evaluated. Independent review of 105 articles identified 17 relevant primary studies of 814 patients. Weighted c about article inclusion was high (0.76). DATA EXTRACTION: Data on population, interventions, outcomes, and methodologic quality of the studies were obtained by duplicate independent review with differences resolved by consensus. Weighted ic on the validity assessment was moderate (0.54). DATA SYNTHESIS: No difference was observed overall between crystalloid and colloid resuscitation with respect to mortality and pulmonary edema; however, the power of the aggregated data was insufficient to detect small but potentially clinically important differences. Subgroup analysis suggested a statistically significant difference in mortality in trauma in favor of crystalloid resuscitation (relative risk 0.39, 95% confidence intervals: 0.17 to 0.89). Several methodologic issues are noteworthy regarding the primary studies, including lack of blinding (except in three studies). The type, dose, and duration of fluid administration and outcomes measured were different across these trials. CONCLUSIONS: Overall, there is no apparent difference in pulmonary edema, mortality, or length of stay between isotonic crystalloid and colloid resuscitation. Crystalloid resuscitation is associated with a lower mortality in trauma patients. Methodologic limitations preclude any evidence-based clinical recommendations. Larger well-designed randomized trials are needed to achieve sufficient power to detect potentially small differences in treatment effects if they truly exist.

Colloids↗
PubMed1991

Internal psychometric properties of the Critical Care Family Needs Inventory.

The aim of this investigation was to examine the internal consistency reliability and construct validity of the Critical Care Family Needs Inventory (CCFNI). Family need data on 677 subjects, collected by 21 nurse investigators in 14 states over a period of 9 years (1980-1988), were used as an aggregate data base. The internal consistency alpha coefficient of the total CCFNI was 0.92. Principal components factor analysis with varimax rotation resulted in a five-factor solution as determined by eigenvalues greater than one, scree plot, magnitude of residuals, simple structure convergence, item loadings, and conceptual clarity. The five dimensions of the CCFNI were labeled as needs for support, comfort, information, proximity, and assurance. Sufficient psychometric properties warrant continuing use of the tool in research and clinical practice.

Adolescent↗