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PubMedDate not supplied

Multidimensional assessment of quality of life in clinical studies.

Four types of issues in conducting a multidimensional assessment of quality of life in clinical studies are presented: practical issues, measurement issues, data quality issues, and data analysis issues. The various issues are described, and ways of dealing with the issues are discussed. Examples are used from the literature and also from the author's multivariate, longitudinal study on quality of life in cardiac transplant patients. Consideration of these issues and knowing options for dealing with them before the study is conducted is imperative. With a carefully thought out approach to better planning of the study, the clinician/investigator can conduct a scientifically sound study with credible results that will provide meaningful direction for improving the quality of life of clinical populations in the future.

Clinical Trials as Topic↗
PubMed2001

Reference data for the quality of life questionnaire EORTC QLQ-C30 in the general German population.

The objective of this study was to obtain age- and sex-specific reference values for the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire QLQ-C30. A randomly selected sample of the German adult population (3015 subjects) was used, 2081 subjects agreed to take part in the investigation. Most of the scales and symptom items of the questionnaire proved to be dependent on age and sex. Men reported fewer symptoms than women. Age differences were even more pronounced. Younger people reported better functioning and fewer symptoms. Compared with the results of a similar Norwegian study (Hjermstad MJ, Fayers PM, Bjordal K, Kaasa S. Health related quality of life in the general Norwegian population assessed by the European Organization for research and treatment of cancer core quality-of-life questionnaire: The QLQ-C30(+3). J Clin Oncol 1998, 16, 1188-1196) the prevalence of some symptoms was markedly less. Norm values for age and sex groups are given and regression analyses are performed which help to calculate expected mean scores. The results show that age and sex differences must be taken into consideration when different groups of cancer patients are compared. The norm values help to interpret quality of life data for clinicians.

Adolescent↗
PubMed2004

GeneLink: a database to facilitate genetic studies of complex traits.

BACKGROUND: In contrast to gene-mapping studies of simple Mendelian disorders, genetic analyses of complex traits are far more challenging, and high quality data management systems are often critical to the success of these projects. To minimize the difficulties inherent in complex trait studies, we have developed GeneLink, a Web-accessible, password-protected Sybase database. RESULTS: GeneLink is a powerful tool for complex trait mapping, enabling genotypic data to be easily merged with pedigree and extensive phenotypic data. Specifically designed to facilitate large-scale (multi-center) genetic linkage or association studies, GeneLink securely and efficiently handles large amounts of data and provides additional features to facilitate data analysis by existing software packages and quality control. These include the ability to download chromosome-specific data files containing marker data in map order in various formats appropriate for downstream analyses (e.g., GAS and LINKAGE). Furthermore, an unlimited number of phenotypes (either qualitative or quantitative) can be stored and analyzed. Finally, GeneLink generates several quality assurance reports, including genotyping success rates of specified DNA samples or success and heterozygosity rates for specified markers. CONCLUSIONS: GeneLink has already proven an invaluable tool for complex trait mapping studies and is discussed primarily in the context of our large, multi-center study of hereditary prostate cancer (HPC). GeneLink is freely available at http://research.nhgri.nih.gov/genelink.

Alleles↗
PubMedDate not supplied

Patient care report cards: an analysis.

In the competitive health care market of the 1990s, health care institutions face a significant number of fiscal challenges that threaten their survival. As part of the survival process, institutions must demonstrate--to the public and to regulatory agencies--that they are measuring the effect of their care structures and processes. Institutions must be willing to share these measurements with the public as well as to use them internally to identify performance problems and document the impact of process improvements or other changes. The report card is a simple, easily understood method for reporting quality data and comparing varying aspects of patient care processes and outcomes. However, as measurements, report cards are not robust enough to serve as the sole source of quality-related data, and interinstitutional comparisons may be misleading. This article explores the new phenomenon known as patient care report cards and discusses their usage in quality measurement and improvement.

Humans↗
PubMed1995

[Time series analysis in environmental epidemiology: short-term effects of air pollution on mortality and morbidity].

This work gives an overview of design and analysis of temporal studies using aggregated data in air pollution epidemiology. In the last years time series are often used to study the short-term association between ambient air pollution levels and aggregated health data. Health endpoints are usually daily mortality and/or daily hospital admission data from routine health registers. Air quality data are commonly obtained from one (or a few) fixed site monitoring stations. To detect the temporal association between the time-pattern in air pollution and the time-pattern in health data particular attention needs to be given to the autocorrelation structure, to the seasonality and long term trend in the data, and to the weather variables. Poisson regression with autocorrelated residuals is the suitable statistical method to analyze time studies. Furthermore, the pollutant variable can be analyzed at different lag-times to account for short latency periods in the manifestation of diseases. Studies with temporal aggregated data show the same disadvantages of the ecologic studies, although, in this case, confounding is less of a problem. Temporal studies usually are based on a large database, so that sufficient power can be achieved to detect even weak associations. Finally, the exposure information on subjects is often better characterized by short-term fluctuations in ambient air quality than is the case in geographic aggregations.

Air Pollutants↗
PubMed1996

[Environment and health: an analysis of intra-urban differentials in the city of São Paulo, Brazil].

A field study undertaken in the city of S. Paulo is presented as part of the project Environment and Health in Developing Countries: An Analysis of Intra-Urban Differentials Using Existing Data financed by the Ministry of Foreign Affairs of the United Kingdom with academic support from the London School of Hygiene and Tropical Medicine (LSHTM). The research aim was to fill in the gaps in the information needed to establish associations between mortality, urbanization and the environment. Statistics were produced by means of existing data collected by city departments, research carried out by universities and census data. Data quality was assessed taking into consideration data coverage, accuracy, and sensibility to pinpoint deprived areas in the city of S. Paulo. Socioeconomic data were used to create a composite index for districts and subdistrict in order to form four socioeconomic zones. Mortality differentials between the zones by five broad age groups (0-4, 5-14, 15-44, 45-64 e 65+) and four ICD chapters (circulatory, respiratory, infectious and parasitic and external causes) are presented. The zoning used showed that 43.8% of S. Paulo residents live in areas under the worst socioeconomic conditions. Health data demonstrated that people living in this areas had higher rates of mortality then those living in the areas with the best conditions. Finally, excess mortality data are analyzed and suggested as a good method for allocating health resources.

Adolescent↗
PubMed1992

A critical appraisal of the literature on the effects of computer-based clinical decision support systems on clinician performance and patient outcomes.

OBJECTIVE: To review the evaluations of computer-based clinical decision support systems (CDSS's). DATA SOURCES: The literature collected in the MEDLARS, EMBASE, SCISEARCH and INSPEC databases was searched from 1974 to the present. The reference lists of relevant articles were reviewed as were conference proceedings. STUDY SELECTION: Prospective, controlled studies were included. Studies were rated for methodological quality. DATA EXTRACTION: Study quality was assessed and data on study setting, subjects, method of allocation, and computer system were collected and verified using a structured form. CONCLUSIONS: There is considerable heterogeneity in both systems evaluated and design features of those systems. Future evaluations of CDSS's should focus on methodological issues in order to enhance overall quality of evaluations.

Clinical Medicine↗
PubMed2003

MicroPreP: a cDNA microarray data pre-processing framework.

The user-friendly MicroPreP framework was developed to transform raw intensity data from cDNA microarrays into high-quality data. The main features of this software are: LOWESS normalisation; merging of DNA microarray data from changing slide versions; outlier detection; and slide quality assessment.

Algorithms↗
PubMed2003

The General Practice Research Network: the capabilities of an electronic patient management system for longitudinal patient data.

PURPOSE: To evaluate the potential of a general practice research database derived directly from de-identified electronic medical records to provide national prescribing data in Australia. To observe the utilisation of a computer-based patient management system over time. To evaluate the impact of the research network participation on data quality in participants' electronic records. METHOD: A random sample of 297 general practitioners (GPs) from 128 practices provided longitudinal patient data from electronic medical records (using Medical Director software) retrospectively from 1 January 1999 to April 2002. The General Practice Research Network (GPRN) database contains approximately 600,000 patients, representing over 4 million prescriptions from 4 million encounters. The quality and representativeness of data for prescribing, morbidity and software usage were evaluated by comparison with National data. RESULTS: Older GPs (> 55) were under-represented, perhaps due to lower computer usage rates, but patient visits were similar to the national distribution. Over time, there were increases in: the quality of prescribing data (with reason for visit/prescription being compulsorily recorded); recording of non-prescribing visits; and the use of other features of the electronic patient management software. CONCLUSIONS: Data derived from electronic general practice records is of sufficient quality to be used to provide national prescribing estimates and has potential value for pharmacoepidemiology and population health monitoring. Such longitudinal data has previously been unavailable in Australia. Monitoring of software usage demonstrates the evolution of the Australian GP user and will be increasingly useful in assessing and improving the quality of electronic medical records.

Australia↗
PubMed1989

Applying quality of life data in practice. Considerations for antihypertensive therapy.

Quality of life issues have become increasingly important in tailoring antihypertensive therapy to individual patients. The application of quality of life data to the practice setting is frequently difficult, however. The effective use of this information requires an understanding of its definition and measurement, as well as of study methods. Quality of life findings may be specific to particular disease states, patient populations, and pharmacologic agents. The addition of hydrochlorothiazide to concurrent methyldopa, propranolol, or captopril therapy has been reported to reduce patients' overall sense of well-being. beta-Adrenergic blockers may exert either positive or negative effects on quality of life. Angiotensin-converting enzyme (ACE) inhibitors may have positive effects on quality of life; however, the cost of therapy is an important consideration. Information on calcium antagonists is limited. The findings of the Treatment of Mild Hypertension Study (TOMHS) may eventually provide comparative quality of life data on the four first-line antihypertensive therapies.

Adult↗
PubMed2001

Derivation of ambient water quality criteria for formaldehyde.

This paper describes the derivation of aquatic life water quality criteria for formaldehyde, developed in accordance with United States Environmental Protection Agency's (USEPA's) Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses. The initial step in deriving water quality criteria was to conduct an extensive literature search to assemble available acute and chronic toxicity data for formaldehyde. The literature search identified a large amount of information on acute toxicity of formaldehyde to fish and aquatic invertebrates. These acute data were evaluated with respect to data quality, and poor quality or uncertain data were excluded from the data base. The resulting data base met the USEPA requirements for criteria derivation by having data for at least one species in at least eight different taxonomic families. One shortcoming of the literature-derived data base, however, was that few studies involved analytical confirmation of nominal formaldehyde concentrations and reported toxicity endpoints. Also, there were relatively few data on chronic toxicity. The acute toxicity data set consisted of data for 12 species of fish, 3 species of amphibians, and 11 species of invertebrates. These data were sufficient, according to USEPA guidelines, to calculate a final acute value (FAV) of 9.15 mg/l, and an acute aquatic life water quality criterion (one-half the FAV) of 4.58 mg/l. A final acute-chronic ratio (ACR) was calculated using available chronic toxicity data and USEPA-recommended conservative default assumptions to account for missing data. Using the FAV and the final ACR (5.69), the final chronic aquatic life water quality criterion was determined to be 1.61 mg/l.

Amphibians↗
PubMed2005

Control, compare and communicate: designing control charts to summarise efficiently data from multiple quality indicators.

Summarising the complex data generated by multiple cross sectional quality indicators in a way that patients, clinicians, managers and policymakers find useful is challenging. A common approach is aggregation to create summary measures such as star ratings and balanced score cards, but these may conceal the detail needed to focus quality improvement. We propose an alternative way of summarising and presenting multiple quality indicators, suitable for use for quality improvement and governance. This paper discusses (1) control charts for repeated measurements of single processes as used in industrial statistical process control (SPC); (2) control charts for cross sectional comparison of many institutions for a single quality indicator (rarely used in industry but commonly proposed for health care); and (3) small multiple graphics which combine control chart signal extraction with efficient graphical presentations for multiple indicators.

Adult↗
PubMed2003

Use of mortality rate after aortic surgery as a performance indicator.

BACKGROUND: Hospital episode statistics (HES) regarding death after aortic surgery were analysed to evaluate their potential value as a performance indicator. METHODS: HES data for all acute hospitals in England and Wales from 1996 to 2001 were analysed retrospectively. In-hospital mortality was calculated for all patients over 40 years of age who underwent abdominal aortic procedures or died in hospital with a primary diagnosis of aortic aneurysm. RESULTS: Some 38 319 cases were identified, of which 8.9 per cent were complex, 46.8 per cent were elective and 44.4 per cent were emergencies. The elective mortality rate was 6.4 per cent overall; that after emergency operation was 35.0 per cent, rising to 41.6 per cent if urgent procedures were excluded and 63.1 per cent if unoperated cases were included. Over the 5-year interval a median of 68 (interquartile range 30-108) elective procedures were carried out by individual hospitals. Considerable variation was identified in the proportion of elderly patients, tertiary referrals and the proportion of emergency admissions that had surgery. CONCLUSION: The use of mortality data may be misleading owing to identifiable differences in case mix and selection. Some redefinition of groups may help to provide more valid data, but ultimately only high-quality data with clinical information are likely to allow meaningful comparisons of performance.

Aorta, Abdominal↗
PubMedDate not supplied

Evaluating the quality of anonymous record linkage using deterministic procedures with the New York State AIDS registry and a hospital discharge file.

Linkage of same-person records across multiple databases relies on high-quality, uniformly available identifying information. These data quality issues become increasingly important when personal names are not available for record linkage. Using deterministic decision criteria, we linked records from two population-based files in the absence of personal names. The sensitivity of anonymous record linkage procedures ranged from 32 to 85 per cent for the two years studied, and the positive predictive value (PPV) ranged from 14 to 99 per cent. Decreasing sensitivity and PPV were primarily attributed to (1) errors in computerized identifying information and (2) the deterministic decision criteria specified for record linkage. An evaluation of the contribution of personal names to the quality of record linkage found no measurable impact.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Improving clinician's coded data entry through the use of an electronic patient record system: 3.5 years experience with a semiautomatic browsing and encoding tool in clinical routine.

This report presents data on clinicians' use of a browsing and encoding utility. Traditional and computerized discharge summaries during three phases of coding ICD-9 diagnoses were compared: phase I (no coding), phase II (manual coding), and phase III (computerized semiautomatic coding). Our data indicate that only 50% of all diagnoses in a discharge summary are encoded manually; using a computerized browsing and encoding utility this rate may increase by 64%; when forced to encode diagnoses manually users may "shift" as much as 84% of relevant diagnoses from the appropriate section to other sections, thereby "bypassing" the need to encode. This effect can be partially reversed by up to 41% with the computerized approach. Using a computerized encoding help can ensure completeness of encoding data (from 46 to 100%). We conclude that the use of a computerized browsing and encoding tool by clinicians can increase data quality and the volume of documented data. Mechanisms bypassing the need to code can be reversed.

Diagnosis↗
PubMed1991

The practical use and evaluation of picture archiving and communication system in the Department of Orthopaedic Surgery.

A picture archiving and communication system (PACS) was started in June 1989 in the outpatient clinic of the Department of Orthopaedic Surgery, Hokkaido University, Sapporo, Japan. The PACS system has several advantages: space savings for storage of images, safe custody and quick access to image data, simultaneous access to image data, the possibility of obtaining good quality data on utilization of images, and applications for medical education and resident training. However, this system has just begun, and several problems must still be solved. In this article, we describe our experiences with the PACS system in the outpatient clinic of the department of orthopaedic surgery.

Hospital Departments↗
PubMed2000

Quality assurance in age estimation based on aspartic acid racemisation.

Estimates of the age of living and dead individuals, obtained in order to answer legal or social questions, require minimum quality standards in order to guarantee data quality. We present an outline strategy (with recommendations) for the attainment of quality assurance in age estimation based on aspartic acid racemisation. The strategy is based on a definition of minimum standards for laboratories, including documentation of procedures, methodology and levels of expertise, and the formulation of guidelines for intralaboratory and interlaboratory quality control.

Age Determination by Teeth↗
PubMed2005

Development of a low-pressure diamond anvil cell and analytical tools to monitor microbial activities in situ under controlled P and T.

We have designed a new low-pressure Diamond Anvil Cell (DAC), calibrated two novel pressure calibrants and validated the use of semi-quantitative Raman and X-ray spectroscopies to monitor the fate of microbes, their metabolism or their cellular components under controlled pressures and temperatures in the 0.1-1.4 GPa and 20-300 degrees C P,T range. The low-pressure DAC has a 250- to 600-microm-thick observation diamond window to allow for lower detection limits and improved microscopic imaging. This new design allows the determination of cellular growth parameters from automated image analysis, which can be correlated with the spectroscopic data obtained on metabolism, ensuring high quality data collection on microbial activity under pressure. The novel pressure sensors offer the ease of use of the well-known ruby scale, while being more sensitive and reacting to pressure variations instantaneously.

Bacteria↗