SEARCH · Search PubMed

Results for “systematic analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources

PubMed2005

[What significance does the topic 'prevention' have in social-psychiatric research? A systematic literature analysis].

AIM OF THE STUDY: Scientists and politicians currently pin great hopes on preventive activities in order to increase the health of particular target populations and to reduce illness related costs. This also holds true for mental disorders, which often show a chronic course of disease. The aim of the present study is to analyse the importance of prevention in social-psychiatric research. METHODS: Including 60 journals, listed in the Science Citation Index or the Social Science Citation Index for the psychosocial field, a systematic literature analysis was done for the year 2004. RESULTS: Only 14 percent of social-psychiatric original research paid attention to prevention. 39 percent of the prevention related publications refer to primary prevention, further 39 percent to secondary prevention, 22 percent focused on tertiary prevention. Research activities concentrated on prevention of substance related disorders as well as early detection or rehabilitation of schizophrenia. CONCLUSIONS: Social psychiatry has only partly responded to the growing importance of prevention in health care. Because many social-psychiatric questions are important for prevention research, social psychiatry should use their competences to facilitate prevention-studies. This holds particularly true for depressive disorders and dementia, which are conditions with high prevalence and substantial illness related costs.

Biomedical Research↗

PubMed1997

[Methods of investigation in clinical cardiology. VIII. Meta-analysis and systematic reviews in cardiology].

Over the last 20 years, the development of meta-analysis has been aimed at obtaining objective synthesis of the available results on specific research questions. The main achievements of meta-analysis include the application of techniques to perform systematic literature searches and to obtain unbiased selection of studies, data extraction and pooled estimates of effect. This paper discusses the methodologic steps to follow when conducting a meta-analysis, with emphasis on study selections, data collection and statistical methods to combine the results from individual studies. We also present a set of guided questions as an aid to critically evaluate the conclusions of published meta-analyses. The application of meta-analytic techniques to cardiology is illustrated using a meta-analysis of the randomized controlled trials of angioplasty versus bypass surgery in the management of patients with ischemic heart disease.

Cardiology↗

PubMed2005

Diagnosis of deep vein thrombosis and pulmonary embolism in pregnancy: a systematic review.

INTRODUCTION: Diagnosing deep vein thrombosis (DVT) and pulmonary embolism (PE) in pregnancy is challenging. Many of the common diagnostic tests, including compression ultrasonography (CUS), ventilation-perfusion scintigraphy (VQ scan) and helical computed tomography (hCT) that have been extensively investigated in non-pregnant patients, have not been appropriately validated in pregnancy. Extrapolating results of diagnostic studies of DVT and PE in non-pregnant patients to those who are pregnant may not be correct because during pregnancy, physiologic and anatomic changes may affect diagnostic test results, presentation and natural history of VTE. METHODS: We performed a systematic analysis of published studies addressing accurate diagnostic testing for DVT and PE in pregnancy to determine the accuracy of these tests in pregnancy. RESULTS: Our initial search yielded 530 articles of which four remained for inclusion, three studies investigating diagnostic testing in patients with a clinical suspicion of DVT or PE and one study in patients with a clinical suspicion of PE. CONCLUSIONS: From our systematic analysis of published studies investigating diagnostic testing for a clinical suspicion of DVT in pregnancy we conclude that; (i) two studies support withholding anticoagulant therapy in pregnant women with a clinical suspicion of DVT and normal results on serial IPG (impedance plethysmography), however, IPG is no longer used; (ii) one study demonstrated that a normal CUS at presentation combined with a normal D-dimer test or an abnormal D-dimer test combined with normal serial CUS appears promising for safely excluding DVT in pregnant patients, but too few patients were included in this pilot-study to draw firm conclusions; and (iii) one study investigated pregnant patients with a clinical suspicion of PE and this study concluded that in patients with normal or non-diagnostic VQ scans, withholding anticoagulant therapy might be safe, but this needs confirmation in larger studies. Recommendations on diagnostic testing of pregnant patients with a clinically suspected DVT or PE are provided.

Female↗

PubMed2004

Systematic toxicological analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD).

In recent years, photodiode array detectors (DADs) have been much improved with respect to wavelength accuracy and resolution, sensitivity, linearity and software operation. UV spectra of drugs measured with up-to-date DADs from different manufacturers are in excellent agreement, have the same quality as measured by a conventional UV spectrometer and are highly reproducible. The calculation of similarity parameters by the DAD software includes the entire range of the spectra compared and allows recognition of very small differences. It was shown in a systematic study of more than 2500 toxicologically relevant substances that UV spectra have a very high specificity with respect to substance structure. Therefore, HPLC-DAD in combination with a comprehensive database of UV spectra and retention parameters is one of the most efficient techniques used in systematic toxicological analysis (STA). Furthermore, the method is advantageous for the identification of metabolites, since in many cases they have the same or very similar UV spectra compared with their respective parent substances and their retention times on reversed-phase columns are shifted in a manner typical of the particular biotransformation reaction. Beside these general aspects, practical applications of HPLC-DAD for STA are reviewed with respect to sample preparation and chromatographic conditions. The efficiency of the method is demonstrated for an example of a routine procedure using liquid-liquid extraction with CH 2 Cl 2 and protein precipitation for sample preparation, a system of three isocratic mobile phases with different acetonitrile/phosphate buffer ratios and RP8 columns for chromatography and a database of 2682 UV spectra and relative retention times for substance identification.

Adult↗

PubMed2006

Among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth dependent on the type of analogue used? A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to answer the following clinical question: among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth per randomized patient dependent on the type of analogue used? Eligible studies were randomized controlled trials (RCTs), published as a full manuscript in a peer-reviewed journal, that contained sufficient information to allow ascertainment of whether randomization was true and whether equality was present between the groups compared. A literature search identified 22 RCTs comparing GnRH antagonists and GnRH agonists that involved 3176 subjects. Where live birth was not reported in a study that fulfilled the inclusion criteria, an effort was made to contact the corresponding authors to retrieve the missing information. If this was not possible, the reported outcome measure, clinical pregnancy or ongoing pregnancy was converted to live birth in 12 studies using published data (Arce et al., 2005). No significant difference was present in the probability of live birth between the two GnRH analogues [odds ratio (OR), 0.86; 95% confidence intervals (CI), 0.72 to 1.02]. This result remains stable in subgroup analysis that ordered the studies by type of population studied, gonadotrophin type used for stimulation, type of agonist protocol used, type of agonist used, type of antagonist protocol used, type of antagonist used, presence of allocation concealment, presence of co-intervention and the way the information on live birth was retrieved. In conclusion, the probability of live birth after ovarian stimulation for IVF does not depend on the type of analogue used for pituitary suppression.

Female↗

PubMedDate not supplied

[Value of systematic toxicological analysis in the management of drug addicts].

This study was carried out between March and December 1985, on 50 drug addicts, including 45 heroin users, hospitalized for detoxication. We compared the clinical informations obtained at the time of admission with the toxicological informations obtained from blood and urinary samples. If the drugs said to have been used over the last 48 hours are always found, in 52% of these cases some other drugs are found too. The reasons of this difference between clinical and toxicological informations are analysed as well as their consequences on diagnosis and treatment. This data finally shows the importance of systematic toxicological analysis in the treatment of drug addicts as well as in the epidemiological studies.

Adolescent↗

PubMed2002

Interlaboratory reproducibility of mobility parameters in capillary electrophoresis for substance identification in systematic toxicological analysis.

An interlaboratory pilot study was performed to determine the reproducibility of mobility parameters in capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC). The study was performed by an intended small number of laboratories (three) that used different brands of instruments (two). The effective mobility was corrected using standards by a method that was recently introduced to obtain a more reproducible migration parameter. A test set of 20 acidic test compounds and 5 reference compounds were analyzed during five days in each laboratory using CZE and MEKC. Buffers used consisted of 90 mM borate set at pH 8.4 (CZE) and 20 mM phosphate, 50 mM sodium dodecyl sulfate set at pH 7.5 (MEKC). Analyses were carried out using fused-silica capillaries at an electric field strength of either 52.6 kV/m or 37.5 kV/m. The interlaboratory reproducibility (mean RSD) of the effective mobility was 3.0% for CZE and 6.7% for MEKC. After applying the correction method, these values became 3.0% for CZE and 3.3% for MEKC, which is adequate for systematic toxicological analysis (STA) applications. A significant improvement of reproducibility for the calculated corrected effective mobility mu(eff)c was observed when variations are high. Therefore, it is recommended to use the correction method in interlaboratory situations, especially when instruments and capillaries from different manufacturers are used.

Calibration↗

PubMed2000

Systematic root cause analysis of adverse drug events in a tertiary referral hospital.

BACKGROUND: Adverse drug events (ADEs) occur frequently, and serious ADEs are associated with mortality or prolonged morbidity. As many ADEs are preventable, identification and modification of systems and processes that permit ADEs has the potential to reduce the rate of ADEs. METHODS: Root cause analysis was systematically employed in a blame-free fashion to investigate the patterns of serious ADEs that occurred during a 29-month period at Hermann Hospital (Houston), and process improvements were implemented on the basis of these findings. The consistently nonpunitive responses to the results of the initial and subsequent root cause analyses was gradually seen, accepted, and ultimately embraced by the hospital staff. RESULTS: The most commonly identified root causes were environmental factors (for example, increased census, increased acuity, change of shift) and staffing issues (for example, personnel new to a unit). Policy changes that led to increased use of forcing or constraining functions (for example, removal of concentrated intravenous potassium solutions from floor stocks) and better personnel support (for example, early awareness and response to localized increases in census and acuity) were particularly effective. Although limited by our lack of active surveillance and not necessarily directly due to the process changes that we implemented, the rate of voluntarily reported serious ADEs/100,000 patient days decreased during this time from 7.2 to 4.0, a decline of 45% (p < 0.001). CONCLUSION: Systematic application of root cause analysis followed by implementation of process changes that target the underlying cause(s) of each event can be successfully implemented in a large hospital.

Adverse Drug Reaction Reporting Systems↗

PubMedDate not supplied

[A theoretical analysis of systematic "parents X progeny" inbreeding in animals in the absence of selection].

Theoretical analysis of the structure of a model population of D. melanogaster under systematic inbreeding--"parents x progeny"--has been conducted using a computer and the original method elaborated. Theoretical relationships between the development of homozygous isolated groups of progeny of 30 generations and their backcrosses with heterozygous and homozygous common ancestors A male and B female were established.

Animals↗

PubMed2002

Nonacute (residual) neuropsychological effects of cannabis use: a qualitative analysis and systematic review.

Because there is a possibility that cannabis or cannabis-like molecules might be used as treatments for certain conditions in the future, it becomes important to consider the possible adverse effects of these compounds. In this paper, the authors review the evidence for persisting effects of nonacute cannabis use on the central nervous system, as reflected by alteration in neuropsychological performance. From the 40 articles that met criteria for inclusion in this review, the authors could not detect consistent evidence for persisting neuropsychological deficits in cannabis users; however, 22 of the 40 studies reported at least some subtle impairments. The inability to reach a firm conclusion results largely from methodological limitations inherent in most studies. These are considered in detail to inform future studies on (nonacute) consequences of cannabis consumption on cognitive abilities.

Cognition Disorders↗

PubMed2007

Systematic pathway analysis using high-resolution fitness profiling of combinatorial gene deletions.

Systematic genetic interaction studies have illuminated many cellular processes. Here we quantitatively examine genetic interactions among 26 Saccharomyces cerevisiae genes conferring resistance to the DNA-damaging agent methyl methanesulfonate (MMS), as determined by chemogenomic fitness profiling of pooled deletion strains. We constructed 650 double-deletion strains, corresponding to all pairings of these 26 deletions. The fitness of single- and double-deletion strains were measured in the presence and absence of MMS. Genetic interactions were defined by combining principles from both statistical and classical genetics. The resulting network predicts that the Mph1 helicase has a role in resolving homologous recombination-derived DNA intermediates that is similar to (but distinct from) that of the Sgs1 helicase. Our results emphasize the utility of small molecules and multifactorial deletion mutants in uncovering functional relationships and pathway order.

DEAD-box RNA Helicases↗

PubMed2026

Complication rates of 16- and 18-gauge needles for native kidney biopsies: a systematic review and proportional meta-analysis.

This systematic review and meta-analysis evaluated complication rates and diagnostic yield reported in studies of adult native kidney biopsy using 16-gauge (16 G) or 18-gauge (18 G) needles. We included randomized trials and cohort studies of real-time ultrasound-guided biopsies, including case series. MEDLINE, Embase, and CENTRAL were searched through October 2024. Two reviewers independently performed study selection, data extraction, and risk of bias assessment using Joanna Briggs Institute tools. Random-effects meta-analyses estimated pooled proportions with 95% confidence intervals (CI), and univariable random-effects meta-regression explored study-level associations with major complications, transfusion, or gross hematuria. We screened 4,499 titles and abstracts and reviewed 319 full-text articles; 62 studies comprising 68 biopsy series were included. The pooled major complication rate in studies using 16 G needles was 1.83% (95% CI: 1.20-2.79) and 1.29% (95% CI: 0.78-2.13) in studies using 18 G needles, with no statistically significant difference. Mean glomerular yield was 18.8 with 16 G and 17.5 with 18 G needles. In study-level meta-regression, studies with higher prevalence of acute kidney injury, lower mean estimated glomerular filtration rate, or lower mean hemoglobin reported higher pooled complication rates. Most studies were single-arm cohorts; between-needle differences therefore reflect indirect study-level contrasts. Interpretation is limited by retrospective design and heterogeneity across studies. Overall, studies using both needle sizes reported low complication rates and similar diagnostic yield, although definitions and reporting varied. Direct comparative studies are needed to determine whether meaningful differences exist.

Humans↗

PubMed1979

Evaluation of a procedure for systematic semiquantitative analysis of glomerular ultrastructure in human renal biopsies.

A method is described for systematic semiquantitative investigation of glomerular ultrastructure in renal biopsies from patients with glomerulonephritis. Three glomeruli per biopsy were studied by electron microscopy. Ten systematically recorded micrographs at x12,000 and a montage covering the whole glomerular cross-section at x3,000 were analyzed from each glomerulus. The severity of each of 34 different ultrastructural lesions was semiquantitatively evaluated on a 4-degree scale, 0 to +++. The usefulness of the method was evaluated by calculating different parameters for the reproducibility of semiquantitative scoring, representativeness of micrographs, and representativeness of glomeruli. The reliability of the method was considered good or acceptable with respect to 17 of the lesions. Ten lesions obtained a high reproducibility of scoring but the usefulness of the scores was limited due to a segmental and/or focal distribution of these lesions. The evaluation of these lesions can be improved by analyzing a larger number of micrographs, or glomeruli, or both. Seven lesions were so rare in the present biopsies that no statistical evaluation was possible. When applied to a large number of biopsies, this practical and useful method allows a reproducible comparison of the patterns of ultrastructural lesions in various types of glomerulonephritis.

Basement Membrane↗

PubMed1998

Methods for spherical data analysis and visualization.

A systematic analysis of the localization of objects in extra-personal space requires a three-dimensional method of documenting location. In auditory localization studies the location of a sound source is often reduced to a directional vector with constant magnitude with respect to the observer, data being plotted on a unit sphere with the observer at the origin. This is an attractive form of data representation as the relevant spherical statistical and graphical methods are well described. In this paper we collect together a set of spherical plotting and statistical procedures to visualize and summarize these data. We describe methods for visualizing auditory localization data without assuming that the principal components of the data are aligned with the coordinate system. As a means of comparing experimental techniques and having a common set of data for the verification of spherical statistics, the software (implemented in MATLAB) and database described in this paper have been placed in the public domain. Although originally intended for the visualization and summarization of auditory psychophysical data, these routines are sufficiently general to be applied in other situations involving spherical data.

Animals↗

PubMed2006

Barriers to participation in clinical trials of cancer: a meta-analysis and systematic review of patient-reported factors.

BACKGROUND: Enrolling participants onto clinical trials of cancer presents an important challenge. We aimed to identify the concerns of patients with cancer about, and the barriers to, participation in clinical trials. METHODS: We did a systematic review to assess studies of barriers to participation in experimental trials and randomised trials for validity and content. We estimated the frequency with which patients identified particular issues by pooling across studies that presented data for barriers to participation in clinical trials as proportions. FINDINGS: We analysed 12 qualitative studies (n=722) and 21 quantitative studies (n=5452). Two qualitative studies inquired of patients who were currently enrolled onto clinical trials, and ten inquired of patients who were eligible for enrolment onto various clinical trials. Barriers to participation in clinical trials were protocol-related, patient-related, or physician-related. The most common reasons cited as barriers included: concerns with the trial setting; a dislike of randomisation; general discomfort with the research process; complexity and stringency of the protocol; presence of a placebo or no-treatment group; potential side-effects; being unaware of trial opportunities; the idea that clinical trials are not appropriate for serious diseases; fear that trial involvement would have a negative effect on the relationship with their physician; and their physician's attitudes towards the trial. Meta-analysis confirmed the findings of our systematic review. INTERPRETATION: The identification of such barriers to the participation in clinical trials should help trialists to develop strategies that will keep to a maximum participation and cooperation in cancer trials, while informing and protecting prospective participants adequately.

Clinical Trials as Topic↗

PubMed2026

Interleukin-23 Receptor and Interleukin-17 Receptor A: Splice Variants, Isoforms and Their Relationship With Periodontitis-A Systematic Review and Bioinformatic Analysis.

This systematic review aimed to: (1) identify the splicing variants of IL23R and IL17RA reported in the literature; (2) perform a multiple alignment analysis to describe the isoforms of IL-23R and IL-17RA; and (3) compare the expression levels of IL-23R, IL-17RA, and their soluble isoforms (sIL-23R and sIL-17RA) in patients with periodontitis and periodontally healthy individuals. The study protocol followed PRISMA guidelines and was registered in PROSPERO (CRD420251267367). Six databases (PubMed, ScienceDirect, Scopus, Web of Science, EBSCO, and Google Scholar) were searched without restrictions on year or language. The descriptors used were: 'Interleukin-23 Receptor,' 'IL-23R,' 'Interleukin-17 Receptor A' 'IL-17RA,' 'Alternative Splicing,' 'Splice Variants,' 'Isoforms,' and 'Periodontitis.' The bioinformatics analysis was performed using CLUSTALW (V.1.83), InterPro and DeepTMHMM. Risk of bias was assessed with the QUIN and JBI tools for cross-sectional studies. Of 104 articles, four in vitro studies and eight cross-sectional studies were included. Qualitative analysis revealed that to date there are 32 splicing variants of the IL23R gene, while only one splicing variant has been reported for IL17RA. CLUSTALW, InterPro and DeepTMHMM analysis showed that these splicing variants result in 23 isoforms which can be soluble forms, complete intracellular peptides, truncated extracellular or intracellular peptides, or complete structures with truncated extracellular and/or intracellular domains. All studies had a low risk of bias. IL-23R and IL-17RA exhibit structural diversity resulting from alternative splicing, with IL-23R demonstrating significantly greater isoform complexity. However, the biological significance of these isoforms in periodontitis remains unclear and requires further investigation.

Humans↗

PubMed2004

[Bibliometric analysis of systematic reviews in the Neonatal Cochrane Collaboration. Its role in evidence-based decision making in neonatology].

INTRODUCTION: The Cochrane Neonatal Collaborative Review Group (CNRG) is one of the most important collaborative review groups registered in the Cochrane Collaboration (CC) and provides a growing and readily accessible source of information to help neonatologists base their care on detailed, critical, and up-to-date reviews of the best available evidence. The objective of this article was to perform a bibliometric analysis (quantitative and qualitative) of the systematic reviews (SR) published in the Neonatal Cochrane Collaboration (NCC) and to identify the subject areas studied by the CNRG in which decision-making in clinical practice is based on the best available evidence. METHODS: We performed a bibliometric analysis of the Cochrane Database of Systematic Reviews in Neonatology, Issue 2, 2003 (n = 147 SR). The following variables were registered in each SR: subject area of the study, authors (number and country), dates (last review and update), characteristics of the clinical trials included (number and type), characteristics of included newborns (number and gestational age), reviewers' conclusions and potential conflicts of interest. RESULTS: The main subject areas of studies in the NCC were respiratory diseases (69 SR) and gastroenterology-nutrition (23 SR). Reviews were relatively scarce on some subjects that are very important in clinical practice in neonatology, such as cardiovascular diseases (10 SR), neurology (10 SR) and infectious diseases (6 SR). All the SR dealt with interventions for the treatment or prevention of diseases of the newborn infant (mainly preterm) and we found no reviews on diagnostic tests. Eighty-two per cent of the SR were signed by 2 or 3 authors, and we found four Bradford's zones of productivity. Ninety-two percent of the authors of SR were from four countries (Australia, United States, United Kingdom and Canada). Seventy-nine percent of all SR were published between 2000 and 2002, and 48 % have been updated. The median number of clinical trials per SR was 5 (range 0-30) and the median number of newborns included per SR was 559 (range 0-5448). Sixty percent of SR also included quasi-randomized clinical trials, and 67 % of SR included only preterm infants. In 54 % of the SR, the reviewers' conclusion was sufficient to infer probable effects (favorable or unfavorable) in clinical practice, and potential conflicts of interest were registered in 22 %. DISCUSSION: Although CC reviews are based on specific guidelines, errors and biases occur, suggesting the need to "review the reviews". The bibliometric analysis of the NCC shows that the quality of published SR varies, and the main conclusion is that almost half of the reviewers' conclusions are insufficient to infer probable effects in clinical practice. There is a lack of scientific evidence on many therapies in neonatology and, at the moment, the SR published in the NCC enable evidence-based decision making mainly in the subject area of respiratory diseases and gastroenterology-nutrition. Challenges for the future include the need for bigger and better clinical trials in this field (with long-term outcomes among surviving children), the preparation of systematic reviews on topics not yet covered, and keeping an increasing number of reviews up-to-date. Every decision in neonatology should be based on a systematic appraisal of the best evidence available in the context of the prevailing values and resources at our disposal.

Bibliometrics↗

PubMed1999

Language sample analysis in the 21st century.

Time requirements inherent in transcription and analysis of spontaneous language samples represent a significant barrier to the regular use of language sample analysis in clinical settings. Taking advantage of the options provided by new large, fast, and affordable personal microcomputers, two language analysis programs, the Systematic Analysis of Language Transcripts and The Child Language Data Exchange System have been developed to provide automated analysis of a wide range of language indices, as well as tools designed to reduce and simplify the time-intensive process of transcribing and analyzing children's language samples from both typical and clinical populations. In this article we provide a historical context for the development of these language analysis programs and a brief introduction to the transcription editors and language sample databases for both systems. In addition, a case study highlighting the interactive use of both analysis systems is provided.

Child↗