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PubMed2005

A review of pharmacologic strategies for switching to atypical antipsychotics.

BACKGROUND: In daily clinical practice, frequent switching of antipsychotic medications is widespread. There are various reasons for switching, including a partial or complete lack of efficacy, adverse side effects, and partial or noncompliance with medication. Patients switched from conventional drugs to oral atypical antipsychotic drugs have been shown to benefit from significant improvements in clinical response and tolerability. This review examines the strategies for switching patients from conventional antipsychotic drugs to both oral and long-acting formulations of atypical antipsychotic drugs that are the recommended treatment in the majority of patients with schizophrenia. DATA SOURCES AND STUDY SELECTION: An electronic literature search of relevant studies using MEDLINE (January 1994-June 2004) was performed using the search terms antipsychotic, atypical, conventional, schizophrenia, and switching. English-language articles, references from bibliographies of reviews, original research articles, and other articles of interest were reviewed. DATA EXTRACTION AND SYNTHESIS: Data quality was determined by publication in the peer-reviewed literature and the most important information identified. Data from clinical trials suggest that switching to an atypical antipsychotic drug is beneficial for the patient with schizophrenia. CONCLUSIONS: If initiated appropriately, switching to atypical antipsychotic medications should not compromise patient functioning; indeed, individualized strategies have been shown to provide continuous treatment efficacy. Switching to atypical antipsychotic therapy should, therefore, be employed as a pharmacologic strategy to maximize patient outcomes.

Journal Article↗

PubMed2001

Beta-blockers in congestive heart failure. A Bayesian meta-analysis.

PURPOSE: Congestive heart failure is an important cause of patient morbidity and mortality. Although several randomized clinical trials have compared beta-blockers with placebo for treatment of congestive heart failure, a meta-analysis quantifying the effect on mortality and morbidity has not been performed recently. DATA SOURCES: The MEDLINE, Cochrane, and Web of Science electronic databases were searched from 1966 to July 2000. References were also identified from bibliographies of pertinent articles. STUDY SELECTION: All randomized clinical trials of beta-blockers versus placebo in chronic stable congestive heart failure were included. DATA EXTRACTION: A specified protocol was followed to extract data on patient characteristics, beta-blocker used, overall mortality, hospitalizations for congestive heart failure, and study quality. DATA SYNTHESIS: A hierarchical random-effects model was used to synthesize the results. A total of 22 trials involving 10 135 patients were identified. There were 624 deaths among 4862 patients randomly assigned to placebo and 444 deaths among 5273 patients assigned to beta-blocker therapy. In these groups, 754 and 540 patients, respectively, required hospitalization for congestive heart failure. The probability that beta-blocker therapy reduced total mortality and hospitalizations for congestive heart failure was almost 100%. The best estimates of these advantages are 3.8 lives saved and 4 fewer hospitalizations per 100 patients treated in the first year after therapy. The probability that these benefits are clinically significant (>2 lives saved or >2 fewer hospitalizations per 100 patients treated) is 99%. Both selective and nonselective agents produced these salutary effects. The results are robust to any reasonable publication bias. CONCLUSIONS: beta-Blocker therapy is associated with clinically meaningful reductions in mortality and morbidity in patients with stable congestive heart failure and should be routinely offered to all patients similar to those included in trials.

Adrenergic beta-Antagonists↗

PubMed1993

Pen-based remote data entry system. A pilot clinical trial.

This study assesses the feasibility of pen-based remote data entry and measures the acceptance of such systems by patients and physicians. Three clinical investigators participated in a phase-I/II clinical trial of escalated doses of chemotherapy followed by Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF). The study included 20 patients with testicular cancer who were treated at three university hospitals. The patients' data obtained in this trial were recorded and stored on a pen-based computer system. A total of 798 data points were recorded for each patient using 33 electronic forms resembling the paper forms used during an earlier phase of the study. The data recorded include the past medical history, inclusion/exclusion criteria, disease staging, therapy documentation, laboratory values and side effects. Both physicians and patients were interviewed directly after using the pen-based remote data entry system. Patients accepted that their physician was taking notes on an electronic form rather than on paper. All patients noted that a pen-based system is superior to a desktop computer when used during an interview. For the investigators electronic data entry takes additional effort, but time savings are realized later with less data clearing and increased data quality. These benefits are important for the study sponsor as well. In conclusion, pen-based remote data entry is a feasible new mode of recording clinical data with concrete benefits to both investigators and sponsors.

Data Display↗

PubMed1991

Magnesium and calcium in drinking water and cardiovascular mortality.

Data on the hardness of drinking water were collected from 27 municipalities in Sweden where the drinking water quality had remained unchanged for more than 20 years. Analyses were made of the levels of lead, cadmium, calcium, and magnesium. These water-quality data were compared with the age-adjusted mortality rate from ischemic heart and cerebrovascular disease for the period 1969-1978. Lead and cadmium were not present in detectable amounts except in one water sample. A statistically significant inverse relationship was present between hardness and mortality from cardiovascular disease for both sexes. Mortality caused by ischemic heart disease was inversely related to the magnesium content, particularly for the men (P less than 0.01). The rather small set of data supports results from previous studies suggesting that a high magnesium level in drinking water reduces the risk for death from ischemic heart disease, especially among men, although the possible importance of confounding factors needs further evaluation.

Cadmium↗

PubMed1999

Quality development in perinatal care -- the OBSQID project. OBStetrical Quality Indicators and Data.

This special communication describes the objectives and strategies of the OBStetrical Quality Indicators and Data collection (OBSQID) project, a pan-European network of researchers, healthcare providers, and professional institutions and associations using agreed key quality indicators and served by a common database. OBSQID is based on the general concept of continuous assessment, management and development of quality of care and is geared to perinatal medicine. It allows contributors to measure, on an on-going basis, the outcomes of care they provide against those of other facilities within their own region or country as well as in Europe. It identifies 'best practices' and allows for the exchange and transfer of knowledge and expertise through 'twinning' or collaborative partnerships. It also assists in setting general quality standards as well as specific guidelines aimed at ensuring all patients high quality, cost-effective care.

Data Collection↗

PubMed2006

Short echo time 1 H magnetic resonance spectroscopy of childhood brain tumours.

AIMS: To explore short echo time (30 ms) 1 H magnetic resonance spectroscopy (MRS) in children with brain tumours and determine the contributions to the characterization of these tumours of the metabolites inositol/myoinositol and glutamate/glutamine, which are not visible at long echo times (135 or 270 ms). METHODS: Over a 12-month period 86 single-voxel MRS investigations were performed on 59 children with various brain tumours on a Siemens Symphony 1.5-T Magnetom using point-resolved spectroscopy and echo time of 30 ms. RESULTS: The procedure was well tolerated, and good-quality data were obtained. N-Acetyl aspartate (NAA)/Choline (Cho) and creatine (Cr)/Cho concentration ratios were significantly (p<0.001) lower in tumour (0.95 and 1.63, respectively) compared with non-involved brain (3.68 and 3.98, respectively) in all histological types. Inositol/Myoinositol (Inos)/Cho ratios were significantly (p<0.05) lower in untreated tumours (1.91) than in treated tumours (3.93) and in non-involved brain (3.32). Inos/Cho ratios were high in diffuse pontine gliomas and low in medulloblastomas and supratentorial primitive neuroectodermal tumours (p<0.01). Glutamate/Glutamine (Glut)/Cho ratios were high in grade 1 astrocytomas (6.4) and unbiopsied optic gliomas (9.84) but low in diffuse pontine gliomas (2.44). Lipids and macromolecules were present in most tumours but in low quantities in non-involved brain. CONCLUSION: Good-quality short echo time MRS data can be collected routinely on children with brain tumours. Inos and Glut levels show greater variability between tumour types than NAA, Cho and Cr present at long echo times, providing improved tumour characterization. Inos/Cho levels differ between untreated and treated tumours and may be useful for treatment monitoring.

Aspartic Acid↗

PubMed1994

Data management for large community trials in Nepal.

The current accessibility and sophistication of hardware and software has made it possible to design high-quality data management systems for community-based trials in resource-poor environments. We designed, implemented, and operated an effective data management system for the Nepal Nutrition Intervention Project Sarlahi (NNIPS), a placebo-controlled community trial to assess the impact of vitamin A supplementation on the preschool mortality of 38,000 children in the Sarlahi district of Nepal. A data center was established in Kathmandu, approximately 8 hr drive from the study area. The trial is now completed and over 200,000 forms have been processed. The majority of potential data discrepancies were identified and corrected by field workers during the interviews. Supervisors and forms editors located at the field office corrected most data errors. Once forms reach Kathmandu, the average number of data entry errors was 3.1 per 10,000 keystrokes for the eight data entry operators employed during the study. Extensive computerized checking of data during data entry found out-of-range, missing, or inconsistent data in only 1% of forms. Timely analysis of field worker performance provided ongoing feedback to supervisors and analysis for the Data Safety and Monitoring Committee, and for publication of results.

Bias↗

PubMed2005

An E-health solution for automatic sleep classification according to Rechtschaffen and Kales: validation study of the Somnolyzer 24 x 7 utilizing the Siesta database.

To date, the only standard for the classification of sleep-EEG recordings that has found worldwide acceptance are the rules published in 1968 by Rechtschaffen and Kales. Even though several attempts have been made to automate the classification process, so far no method has been published that has proven its validity in a study including a sufficiently large number of controls and patients of all adult age ranges. The present paper describes the development and optimization of an automatic classification system that is based on one central EEG channel, two EOG channels and one chin EMG channel. It adheres to the decision rules for visual scoring as closely as possible and includes a structured quality control procedure by a human expert. The final system (Somnolyzer 24 x 7) consists of a raw data quality check, a feature extraction algorithm (density and intensity of sleep/wake-related patterns such as sleep spindles, delta waves, SEMs and REMs), a feature matrix plausibility check, a classifier designed as an expert system, a rule-based smoothing procedure for the start and the end of stages REM, and finally a statistical comparison to age- and sex-matched normal healthy controls (Siesta Spot Report). The expert system considers different prior probabilities of stage changes depending on the preceding sleep stage, the occurrence of a movement arousal and the position of the epoch within the NREM/REM sleep cycles. Moreover, results obtained with and without using the chin EMG signal are combined. The Siesta polysomnographic database (590 recordings in both normal healthy subjects aged 20-95 years and patients suffering from organic or nonorganic sleep disorders) was split into two halves, which were randomly assigned to a training and a validation set, respectively. The final validation revealed an overall epoch-by-epoch agreement of 80% (Cohen's kappa: 0.72) between the Somnolyzer 24 x 7 and the human expert scoring, as compared with an inter-rater reliability of 77% (Cohen's kappa: 0.68) between two human experts scoring the same dataset. Two Somnolyzer 24 x 7 analyses (including a structured quality control by two human experts) revealed an inter-rater reliability close to 1 (Cohen's kappa: 0.991), which confirmed that the variability induced by the quality control procedure, whereby approximately 1% of the epochs (in 9.5% of the recordings) are changed, can definitely be neglected. Thus, the validation study proved the high reliability and validity of the Somnolyzer 24 x 7 and demonstrated its applicability in clinical routine and sleep studies.

Adult↗

PubMed2006

The effect of misclassification errors on case mix measurement.

Case mix systems have been implemented for hospital reimbursement and performance measurement across Europe and North America. Case mix categorizes patients into discrete groups based on clinical information obtained from patient charts in an attempt to identify clinical or cost difference amongst these groups. The diagnosis related group (DRG) case mix system is the most common methodology, with variants adopted in many countries. External validation studies of coding quality have confirmed that widespread variability exists between originally recorded diagnoses and re-abstracted clinical information. DRG assignment errors in hospitals that share patient level cost data for the purpose of establishing cost weights affects cost weight accuracy. The purpose of this study is to estimate bias in cost weights due to measurement error of reported clinical information. DRG assignment error rates are simulated based on recent clinical re-abstraction study results. Our simulation study estimates that 47% of cost weights representing the least severe cases are over weight by 10%, while 32% of cost weights representing the most severe cases are under weight by 10%. Applying the simulated weights to a cross-section of hospitals, we find that teaching hospitals tend to be under weight. Since inaccurate cost weights challenges the ability of case mix systems to accurately reflect patient mix and may lead to potential distortions in hospital funding, bias in hospital case mix measurement highlights the role clinical data quality plays in hospital funding in countries that use DRG-type case mix systems. Quality of clinical information should be carefully considered from hospitals that contribute financial data for establishing cost weights.

Diagnosis-Related Groups↗

PubMed2000

Physicians and the pharmaceutical industry: is a gift ever just a gift?

CONTEXT: Controversy exists over the fact that physicians have regular contact with the pharmaceutical industry and its sales representatives, who spend a large sum of money each year promoting to them by way of gifts, free meals, travel subsidies, sponsored teachings, and symposia. OBJECTIVE: To identify the extent of and attitudes toward the relationship between physicians and the pharmaceutical industry and its representatives and its impact on the knowledge, attitudes, and behavior of physicians. DATA SOURCES: A MEDLINE search was conducted for English-language articles published from 1994 to present, with review of reference lists from retrieved articles; in addition, an Internet database was searched and 5 key informants were interviewed. STUDY SELECTION: A total of 538 studies that provided data on any of the study questions were targeted for retrieval, 29 of which were included in the analysis. DATA EXTRACTION: Data were extracted by 1 author. Articles using an analytic design were considered to be of higher methodological quality. DATA SYNTHESIS: Physician interactions with pharmaceutical representatives were generally endorsed, began in medical school, and continued at a rate of about 4 times per month. Meetings with pharmaceutical representatives were associated with requests by physicians for adding the drugs to the hospital formulary and changes in prescribing practice. Drug company-sponsored continuing medical education (CME) preferentially highlighted the sponsor's drug(s) compared with other CME programs. Attending sponsored CME events and accepting funding for travel or lodging for educational symposia were associated with increased prescription rates of the sponsor's medication. Attending presentations given by pharmaceutical representative speakers was also associated with nonrational prescribing. CONCLUSION: The present extent of physician-industry interactions appears to affect prescribing and professional behavior and should be further addressed at the level of policy and education.

Attitude↗

PubMed2004

Pharmacotherapy for patellofemoral pain syndrome.

BACKGROUND: Patellofemoral pain syndrome (PFPS) is common among adolescents and young adults. It is characterised by pain behind or around the patella and crepitations, provoked by ascending or descending stairs, squatting, prolonged sitting with flexed knees, running and cycling. The symptoms impede function in daily activities or sports. Pharmacological treatments focus on reducing pain symptoms (non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticosteroids), or restoring the assumed underlying pathology (compounds containing glucosamine to stimulate cartilage metabolism, anabolic steroids to increase bone density of the patella and build up supporting muscles). In studies, drugs are usually applied in addition to exercises aimed at building up supporting musculature. OBJECTIVES: This review aims to summarise the evidence of effectiveness of pharmacotherapy in reducing anterior knee pain and improving knee function in people with PFPS. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group and Cochrane Rehabilitation and Related Therapies Field trials registers, the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2003), PEDro (up to January 2004), MEDLINE (1966 to January 2004), EMBASE (1988 to January 2004), and CINAHL (1982 to January 2004). SELECTION CRITERIA: Controlled trials (randomised or not) comparing pharmacotherapy with placebo, different types of pharmacotherapy, or pharmacotherapy to other therapies for people with PFPS. DATA COLLECTION AND ANALYSIS: The literature search yielded 780 publications. Eight trials were included, of which three were of high quality. Data were analysed qualitatively using best evidence synthesis, because meta-analysis was impeded by differences in route of administration of drugs, care programs and outcome measures. MAIN RESULTS: Four trials (163 participants) studied the effect of NSAIDs. Aspirin compared to placebo in a high quality trial produced no significant differences in clinical symptoms and signs. Naproxen produced significant short term pain reduction when compared to placebo, but not when compared to diflunisal. Laser therapy to stimulate blood flow in tender areas led to more satisfied participants than tenoxicam, though not significantly. Two high quality RCTs (84 participants) studied the effect of glycosaminoglycan polysulphate (GAGPS). Twelve intramuscular injections in six weeks led to significantly more participants with a good overall therapeutic effect after one year, and to significantly better pain reduction during one of two activities. Five weekly intra-articular injections of GAGPS and lidocaine were compared with intra-articular injections of saline and lidocaine or no injections, all with concurrent quadriceps training. Injected participants showed better function after six weeks, though only the difference between GAGPS injected participants and non-injected participants was significant. The differences had disappeared after one year. One trial (43 participants) found that intramuscular injections of the anabolic steroid nandrolone phenylpropionate significantly improved both pain and function compared to placebo injections. REVIEWERS' CONCLUSIONS: There is only limited evidence for the effectiveness of NSAIDs for short term pain reduction in PFPS. The evidence for the effect of glycosaminoglycan polysulphate is conflicting and merits further investigation. The anabolic steroid nandrolone may be effective, but is too controversial for treatment of PFPS.

Anabolic Agents↗

PubMed2002

Aligning experimental design with bioinformatics analysis to meet discovery research objectives.

The utility of genomic technology and bioinformatic analytical support to provide new and needed insight into the molecular basis of disease, development, and diversity continues to grow as more research model systems and populations are investigated. Yet deriving results that meet a specific set of research objectives requires aligning or coordinating the design of the experiment, the laboratory techniques, and the data analysis. The following paragraphs describe several important interdependent factors that need to be considered to generate high quality data from the microarray platform. These factors include aligning oligonucleotide probe design with the sample labeling strategy if oligonucleotide probes are employed, recognizing that compromises are inherent in different sample procurement methods, normalizing 2-color microarray raw data, and distinguishing the difference between gene clustering and sample clustering. These factors do not represent an exhaustive list of technical variables in microarray-based research, but this list highlights those variables that span both experimental execution and data analysis.

Computational Biology↗

PubMed2003

Summary report: Missing data and pedigree and genotyping errors.

Genetic epidemiology is faced with mapping complex traits to genes with relatively small effects whose phenotypes may be modulated by temporal factors. To do this, detailed and accurate data must be available on families, perhaps collected over time. The Framingham Heart Study data supplied to Genetic Analysis Workshop 13 (GAW13), along with its simulated counterpart, contain longitudinal measurements and genomic scan data on 2,885 individuals in 330 families, and offer an opportunity to examine data quality and completeness issues as they affect analytical conclusions. Six GAW13 contributions applied methods to deal with missing data, both phenotypic and genotypic, at a single time point and longitudinally, and with possible errors in pedigree structure and genotypes. The methods included missing phenotypic data imputation by Markov chain Monte Carlo sampling, propensity scoring, regression, and adjusted mean values, as well as the assessment of transmission-disequilibrium tests when missing marker data may be allele-specific. Pedigree structural errors were found by genome-wide allele-sharing probabilities, while Mendelian consistent genotype errors were evaluated through likelihoods of double-recombination events. Each of the methods reviewed here offered insights into how to better take advantage of large, time-dependent, familial data sets. However, no one of them dealt with the longitudinal and familial aspects simultaneously. Overall, more consideration needs to be given to the effects that missing data and data errors have on our ability to map complex traits efficiently and accurately.

Cardiovascular Diseases↗

PubMed1995

Sources of pollution and sediment contamination in Newark Bay, New Jersey.

A review of historical water quality and sediment quality data and chemical body burdens in biota reveals significant levels of a wide range of chemicals and water quality stressors throughout the Newark Bay, New Jersey estuary. The estuary, which encompasses the Passaic River, Hackensack River, Kill van Kull, and the Arthur Kill, has been heavily impacted by both industrial and urban expansion for more than 200 years. The available information was sufficient to identify the major sources of pollution and the contributions of various metals and organic chemicals to the aquatic environment. Mass loadings for several chemicals and water quality parameters were estimated for publicly owned treatment works (POTWs) and combined sewer overflows (CSOs), industrial waste discharged either directly to the estuary or through POTWs, stormwater runoff, and accidental spills of petroleum products and hazardous chemicals. The recent trend toward regionalized waste treatment systems to provide secondary levels of treatment have provided some reductions of overall contaminant mass loadings. However, CSOs remain a significant source of untreated waste in the estuary. Additionally, the magnitude of the major sources relative to the ability of the estuary to absorb and dilute the various waste streams suggests that much more must be done to reduce chemical inputs at the source.

History, 19th Century↗

PubMed2006

[Data sources in epidemiology].

The use of large databases has a high potential for future epidemiological research. Databases consisting of primary data as well as routine data that are mainly collected for administrative purposes will be of interest. This paper presents some large databases and some that are most relevant for epidemiological research, respectively, and shows how they might be exploited for research purposes. To make better use of large databases there are new requirements and challenges that we have to face regarding appropriate methods for their analysis. Some examples of such methods are given. An example of pharmaco-epidemiology illustrates linkage of several administrative databases and specific problems that have to be solved in this context. Finally, future challenges are discussed that have to be overcome on the way towards establishment, maintenance and analysis of large databases, especially regarding data protection, data quality and regular updates.

Computer Security↗

PubMed2006

REPDOSE: A database on repeated dose toxicity studies of commercial chemicals--A multifunctional tool.

A database for repeated dose toxicity data has been developed. Studies were selected by data quality. Review documents or risk assessments were used to get a pre-screened selection of available valid data. The structure of the chemicals should be rather simple for well defined chemical categories. The database consists of three core data sets for each chemical: (1) structural features and physico-chemical data, (2) data on study design, (3) study results. To allow consistent queries, a high degree of standardization categories and glossaries were developed for relevant parameters. At present, the database consists of 364 chemicals investigated in 1018 studies which resulted in a total of 6002 specific effects. Standard queries have been developed, which allow analyzing the influence of structural features or PC data on LOELs, target organs and effects. Furthermore, it can be used as an expert system. First queries have shown that the database is a very valuable tool.

Animals↗

PubMed2002

Feasibility issues in reproductive biomonitoring of female flight attendants and teachers.

Flight attendants (FAs) may be at risk of adverse reproductive outcomes. We investigated the feasibility of biomonitoring studies in this mobile workforce. Forty-five female FAs and 26 female teachers (referents) collected daily urine and saliva samples for one menstrual cycle, provided daily diary data for approximately three months, and wore a wrist monitor to measure sleep disruption. A transport system enabled FAs to store samples while traveling. Overall, participation rates were low (37%) but of those recruited, over 90% of FAs and teachers completed the biomonitoring cycle. Data collection and sample integrity were not diminished by travel. Study methods resulted in good compliance and high quality data. It is possible to conduct studies of menstrual cycle function, sleep disruption, and circadian rhythm disruption in a mobile workforce potentially exposed to reproductive hazards.

Adolescent↗

PubMed2005

Case-control study on analgesics and nephropathy (SAN): protocol.

BACKGROUND: The association between intake of non-phenacetin-containing analgesics and the occurrence of chronic renal failure is still controversially discussed. A new epidemiologic study was planned and conducted in Germany and Austria. METHODS/DESIGN: The objective of the international, multicenter case-control study was to evaluate the association between end-stage renal disease (ESRD) and use of non-phenacetin-containing analgesics with particular emphasis on combined formulations. A targeted sample of 1000 new (incident) dialysis patients, aged less than 50 years, was planned to recruit between January 1, 2001 and December 31, 2004. The age limit was chosen to avoid contamination of the study population with phenacetin-containing analgesics to the extent possible. Four control subjects per ESRD case, matched by age, sex, and region were selected from the population living in the region the case came from. Lifetime exposure to analgesics and potential renal risk factors were recorded in a single face-to-face interview. A set of aids was introduced to reinforce the memory of study participants. A standardized, pre-tested interview questionnaire (participants), a medical documentation sheet (physicians in dialysis centres), a logbook for all activities (dialysis centres) were used to collect the necessary data. Quality management consisted of the standardized procedures, (re-) training and supervision of interviewers, regular checks of all incoming data for completeness and plausibility. The study is scientifically independent and governed by a international Scientific Advisory Committee that bridged the gap between the sponsoring companies and the investigators. Also other advisory groups assisted the managing committee of the study. All relevant German and Austrian nephrological associations supported the study, and the study design was carefully reviewed and approved by the Kidney Foundation of Germany. DISCUSSION: The study is expected to answer the main research question by end 2005. There is however a high potential for various biases that we tried to address with adequate measure. One limitation however cannot be overcome: The methodologically needed age-limitation of the study will make it not easy to generalize the results to age groups over 50 years. It might be suggested to repeat the study for persons over 50 years in 10 years when contamination with phenacetin use early in life is likely to be outgrown.

Analgesics↗