SEARCH · PubMed Health

Results for “Databases, Bibliographic”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 235 records · Page 13Linked to original sources

PubMed2005

PubMed perspective of family medicine research: where does it stand?

OBJECTIVE: The aim of this study was to obtain a view of family medicine research by analyzing PubMed citations from 1960-2003. METHOD: Family practice (FP) citations in PubMed from 1960 to 2003 were downloaded in MEDLINE format. This was written into relation database using 'PubMed Grabber/Analyzer' software developed at University of Kelaniya, Sri Lanka. Search Query Language (SQL) and online PubMed queries were used for further analysis. RESULTS: There were 50288 FP citations from 80 countries. Of these, 33712 (67%) citations were from 15 FP journals. United Kingdom (18760), United States (13584), Australia (3262), Canada (1848), Germany-west (1340) were the five countries which had the most citations and 22 countries had less than 5 citations. Van Weel C (118), Geyman JP (116), Olesen F (87), Jones R (83) and Knottnerus JA (82) were numerically, the top five authors. Only 921 authors had more than 10 citations and the vast majority of authors had only one citation. Letters (5121), review (2715), editorial (2259), randomized controlled trials-RCT (1585) and Meta-analysis (44) were the top publication types. 40 citations found under 'qualitative research'. Discussion. The relatively few PubMed FP citations (50288) are by a small number of academics in developed countries. Citations showed an upsurge from the mid 1980s to the late 1990's but reached a plateau in the new millennium. Compared to PubMed citations from 1960-2003 in other specialties such as 2737655 for public health, 1151194 for cardiology & cardiovascular diseases and 318538 for medical informatics, the 50288 FP citations were paltry. Paucity of RCT (1585) and meta-analysis (44) was noted. The low 'qualitative research' citations (44) could have been due to the late introduction of the MeSH concept in 2003. CONCLUSIONS: Priority should be given to increase FP research and also to ensure the indexing of FP journals that are not currently indexed in PubMed. Efforts to increase citations in Medline may not give the desired results because of low priority given primary care specialties such as family medicine in the USA. Alternative solution of a separate bibliographic database for FP similar to PsycInfo may be too costly.

Family Practice↗

PubMed1998

Nonsurgical repigmentation therapies in vitiligo. Meta-analysis of the literature.

OBJECTIVE: To assess the effectiveness and safety of nonsurgical repigmentation therapies in localized and generalized vitiligo by means of a meta-analysis. DATA SOURCES: Computerized searches of bibliographic databases, a complementary manual literature search, and contacts with researchers and pharmaceutical firms. STUDY SELECTION: Predefined selection criteria were applied to both randomized and nonrandomized controlled trials. DATA EXTRACTION: Two investigators independently assessed the articles for inclusion. When there was a disagreement, a third investigator was consulted. DATA SYNTHESIS: Sixty-three studies were found on therapies for localized vitiligo. Of these, 10 of 11 randomized controlled trials and 29 of 110 patient series were included. One hundred seventeen studies on therapies for generalized vitiligo were found. Of these, 10 of 22 randomized controlled trials and 46 of 231 patient series were included. Among randomized controlled trials on localized vitiligo, the pooled odds ratio vs placebo was significant for topical class 3 corticosteroids (14.32; 95% confidence interval [CI], 2.45-83.72). In the patient series, topical class 3 and class 4 corticosteroids carried the highest mean success rates (56% [95% CI, 50%-62%] and 55% [95% CI, 49%-61%], respectively). Side effects were reported mostly with topical psoralen and intralesional and class 4 corticosteroids. In the randomized controlled trials on generalized vitiligo, the odds ratio vs placebo was significant for oral methoxsalen plus sunlight (23.37; 95% CI, 1.33-409.93), oral psoralen plus sunlight (19.87; 95% CI, 2.37-166.32), and oral trioxsalen plus sunlight (3.75; 95% CI, 1.24-11.29). In the series, the highest mean success rates were achieved with narrowband UV-B (63%; 95% CI, 50%-76%), broadband UV-B (57%; 95% CI, 29%-82%), and oral methoxsalen plus UV-A therapy (51%; 95% CI, 46%-56%). Oral methoxsalen plus UV-A was associated with the highest rates of side effects. No side effects were reported with UV-B therapy. CONCLUSIONS: Class 3 corticosteroids and UV-B therapy are the most effective and safest therapies for localized and for generalized vitiligo, respectively.

Humans↗

PubMed1998

A systematic review of autologous transplantation methods in vitiligo.

OBJECTIVE: A systematic review of the effectiveness, safety, and applicability of autologous transplantation methods in vitiligo. DATA SOURCES: Computerized searches of bibliographical databases, a complementary manual literature search, and contacts with researchers and pharmaceutical firms. STUDY SELECTION: Predefined selection criteria were applied to all studies found. DATA EXTRACTION: Two investigators independently assessed the articles for inclusion. When there was a disagreement, a third investigator was consulted. DATA SYNTHESIS: Sixty-three studies were found, of which 16 reported on minigrafting, 13 on split-thickness grafting, 15 on grafting of epidermal blisters, 17 on grafting of cultured melanocytes, and 2 on grafting of noncultured epidermal suspension. Of these, 39 patient series were included. The highest mean success rates (87%) were achieved with split-skin grafting (95% confidence interval, 82%-91%), and epidermal blister grafting (87%) (95% confidence interval, 83%-90%). The mean success rate of 5 culturing techniques varied from 13% to 53%. However, in 4 of the 5 culturing methods, fewer than 20 patients were studied. Minigrafting had the highest rates of adverse effects but was the easiest, fastest, and least expensive method. CONCLUSIONS: Because no controlled trials were included, treatment recommendations should be formulated with caution. Split-thickness and epidermal blister grafting can be recommended as the most effective and safest techniques. No definite conclusions can be drawn about the effectiveness of culturing techniques because only a small number of patients have been studied. The choice of method also depends on certain disease characteristics and the availability of specialized personnel and equipment.

Humans↗

PubMed2002

The suitability of quality-of-life questionnaires for psoriasis research: a systematic literature review.

OBJECTIVE: To critically appraise the suitability of current quality-of-life (QOL) questionnaires for psoriasis research. DATA SOURCES: Computerized searches of 5 bibliographic databases. QUESTIONNAIRE SELECTION: Predefined criteria were used to identify QOL questionnaires in dermatologic studies. Two investigators independently assessed and agreed on multidimensional generic, dermatology-specific, and psoriasis-specific QOL questionnaires for inclusion. DATA EXTRACTION: Data were extracted on the internal structure, reliability, and validity of the included questionnaires. DATA SYNTHESIS: Three generic, 3 dermatology-specific, and none of the psoriasis-specific questionnaires met the inclusion criteria: the Nottingham Health Profile (NHP), the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), the Sickness Impact Profile (SIP), the Dermatology Quality of Life Scales (DQOLS), the Dermatology-Specific Quality of Life Instrument (DSQL), and the Skindex-29. The generic NHP, SF-36 and SIP are well established, reliable, and valid. Although the data are not conclusive, the SF-36 was useful to assess effects of psoriasis on its component scales. The dermatology-specific DQOLS, DSQL, and Skindex-29 are relatively new and, therefore, less widely tested. Available psychometric data demonstrated the reliability and validity of all 3 dermatology-specific questionnaires. The Skindex-29 was also useful to assess change. CONCLUSIONS: None of the identified psoriasis-specific questionnaires met the inclusion criteria. Data on the suitability of the included questionnaires for psoriasis research were relatively sparse. The included generic questionnaires allow comparisons with nondermatologic diseases but do not allow assessment of relevant dermatology-specific aspects and are not sensitive to subtle effects of psoriasis on QOL. On the basis of the psychometric data of the present review, we find the Skindex-29 to be the most valuable dermatology-specific questionnaire for psoriasis research. Combination of the Skindex-29 with the generic SF-36 combines the merits of both types of questionnaires and we therefore recommend this combination.

Adaptation, Psychological↗

PubMed2001

Evidence- and consensus-based practice guidelines for the diagnosis of irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome (IBS) presents a significant diagnostic and management challenge for primary care practitioners. Improving the accuracy and timeliness of diagnosis may result in improved quality and efficiency of care. OBJECTIVE: To systematically appraise the existing diagnostic criteria and combine the evidence with expert opinion to derive evidence- and consensus-based guidelines for a diagnostic approach to patients with suspected IBS. METHODS: We performed a systematic literature review (January 1966-April 2000) of computerized bibliographic databases. Articles meeting explicit inclusion criteria for diagnostic studies in IBS were subjected to critical appraisal, which formed the basis of guideline statements presented to an expert panel. To develop a diagnostic algorithm, an expert panel of specialists and primary care physicians was used to fill in gaps in the literature. Consensus was developed using a modified Delphi technique. RESULTS: The systematic literature review identified only 13 published studies regarding the effectiveness of competing diagnostic approaches for IBS, the accuracy of diagnostic tests, and the internal validity of current diagnostic symptom criteria. Few studies met accepted methodological criteria. While symptom criteria have been validated, the utility of endoscopic and other diagnostic interventions remains unknown. An analysis of the literature, combined with consensus from experienced clinicians, resulted in the development of a diagnostic algorithm relevant to primary care that emphasizes a symptom-based diagnostic approach, refers patients with alarm symptoms to subspecialists, and reserves radiographic, endoscopic, and other tests for referral cases. The resulting algorithm highlights the reliance on symptom criteria and comprises a primary module, 3 submodules based on the predominant symptom pattern (constipation, diarrhea, and pain) and severity level, and a subspecialist referral module. CONCLUSIONS: The dearth of available evidence highlights the need for more rigorous scientific validation to identify the most accurate methods of diagnosing IBS. Until such time, the diagnostic algorithm presented herein could inform decision making for a range of providers caring for primary care patients with abdominal discomfort or pain and altered bowel function suggestive of IBS.

Algorithms↗

PubMed1998

Substance abuse in children: prediction, protection, and prevention.

OBJECTIVE: To review the latest studies on risk and protective factors for the development of substance abuse and the effectiveness of prevention interventions for the pediatric population. DATA SOURCES: Multiple bibliographic databases, including MEDLINE and ERIC, were used to develop a comprehensive review of the literature on substance abuse prevention during the last 10 years. Selected indexing terms included substance abuse prevention, risk factors, and protective factors. Research monographs from the National Institute on Drug Abuse and the Center for Substance Abuse Prevention were used, along with information from authors of prevention curricula. STUDY SELECTION: Study populations included children from birth through adolescence who were enrolled in controlled, prospective, and/or longitudinal studies of either protective or risk factors for the development of substance abuse or response to substance abuse prevention programs. Studies of adult patients that investigated predisposing risk factors for substance abuse (eg, genetic implications) were also used. Care was taken to ensure studies included children from diverse racial and social backgrounds. DATA EXTRACTION: Information was abstracted and summarized from peer-reviewed publications. Controlled random-designed studies were used to determine prevention program efficacy. DATA SYNTHESIS: Main results of the review are summarized in a qualitative format. CONCLUSIONS: Factors that contribute to the emergence of substance abuse in the pediatric population are multifactorial. Behavioral, emotional, and environmental factors that place children at risk for the development of substance abuse may be remediated through prevention and intervention programs that use research-based, comprehensive, culturally relevant, social resistance skills training and normative education in an active school-based learning format.

Adolescent↗

PubMed2002

A systematic review of nonpharmacological and nonsurgical therapies for gastroesophageal reflux in infants.

BACKGROUND: Nonpharmacological and nonsurgical measures are often recommended for gastroesophageal reflux disease (GERD) in infants, despite ambiguous supporting evidence. OBJECTIVE: To conduct a systematic review of rigorously evaluated nonpharmacological and nonsurgical therapies for GERD in infants. DESIGN/METHODS: We searched online bibliographic databases, including MEDLINE, EMBASE, the Cochrane Collaboration and Clinical Trials Database, and alternative medicine databases for the terms gastroesophageal reflux and infants. We selected randomized controlled trials of nonpharmacological and nonsurgical GERD therapies in otherwise healthy infants. Data were extracted from the selected articles regarding reflux, emetic episodes and intraesophageal pH. RESULTS: We identified 43 relevant studies, of which 10 met the selection criteria. These studies examined positioning, pacifier use, and feeding changes. Positioning at a 60 degree elevation in an infant seat was found to increase reflux compared with the prone position. No significant difference was shown between the flat and head-elevated prone positions. The impact of pacifier use on reflux frequency was equivocal and dependent on infant position. The protein content of formula was not found to affect reflux. Although no study demonstrated a significant reflux-reducing benefit of thickened infant foods compared with placebo, 1 study detected a significant benefit of formula thickened with carob bean gum compared with rice flour (pH<4 for 5% vs 8% of time). Another study showed that if supplementing with dextrose 5% water or dextrose 10% water, the lower-osmolality fluid was associated with less reflux. CONCLUSIONS: Many conservative measures commonly used to treat GERD in infants have no proven efficacy. Although thickened formulas do not appear to reduce measurable reflux, they may reduce vomiting. Further studies with clinical outcomes are needed to answer questions about efficacy definitively.

Gastroesophageal Reflux↗

PubMed2003

Racial and ethnic disparities in health care for adolescents: a systematic review of the literature.

OBJECTIVE: To identify the extent of racial and ethnic disparities in primary care, mental health care, reproductive health care, and asthma care for adolescents independent of socioeconomic status (SES). DATA SOURCES: Systematic review of the scientific literature using standard bibliographic databases. STUDY SELECTION: Inclusion criteria were (1) studies published in the past 12 years, (2) analyses included children and adolescents aged 17 years and younger, and (3) data analyzed by racial/ethnic groups while accounting for SES. A total of 203 studies were reviewed, of which 31 met the criteria for inclusion: 14 of 65 studies on primary care, 11 of 61 studies on mental health care, 2 of 50 studies on reproductive health, and 4 of 27 studies on asthma services. DATA EXTRACTION: Data from tables in the selected studies were used to determine whether minority children and adolescents received fewer, greater, or the same health care services as white children and youth after taking into account SES. DATA SYNTHESIS: Black youth received fewer primary care services in 8 studies, whereas in 4 studies no disparity was noted. Hispanic youth received fewer primary care services in 6 studies, whereas no disparity was noted in 5. One study did not include Hispanic subjects. In 2 studies minority youth, combined into a single category, received fewer services than did white youth. In a total of 6 studies black youth received fewer mental health services, whereas in 3 studies no disparity was noted and in 1 study black youth received a greater number of services. In 3 studies Hispanic youth received fewer mental health services, and in 3 studies there were no group differences. In 1 study, with racial and ethnic groups combined in a single category, minority children and youth received fewer mental health services than white subjects. Three studies did not include Hispanic subjects. Too few studies of reproductive and asthma care were available to draw conclusions. CONCLUSIONS: These results suggest that racial and ethnic disparities, independent of SES, exist in selected areas of adolescent health care. More studies are needed to better understand the extent and causes of these findings.

Adolescent↗

PubMed1996

Efficacy of bronchodilator therapy in bronchiolitis. A meta-analysis.

OBJECTIVE: To determine if bronchodilators are efficacious in treating bronchiolitis. DATA SOURCES: A search of bibliographic databases (MEDLINE, Excerpta Medica, and Reference Update) for bronchiolitis and albuterol or ipratropium bromide, or adrenergic agents or bronchodilator agents. Reference lists were also used. STUDY SELECTION: Randomized, placebo-controlled trials of bronchodilator treatment in bronchiolitis were selected by 2 investigators. Fifteen of 89 identified publications met the selection criteria. DATA EXTRACTION: Investigators independently abstracted data for 3 outcomes: clinical score, oxygen saturation, and hospitalization. Clinical score was measured as a dichotomous variable (score +/- improved) or continuous variable (average score). DATA SYNTHESIS: For primary analysis, data were pooled from 8 trials of children with first-time wheezing. The effect size for average score was -0.32 (95% confidence interval [CI], -0.54 to -0.11; P < .01), favoring treatment; the relative risk for score +/- improved was 0.76 (95% CI, 0.60 to 0.95; P = .02), favoring treatment. Bronchodilators had no effect on hospitalization (relative risk, 0.85; 95% CI, 0.47 to 1.53; P = .58), but co-interventions may have been administered prior to this outcome. The results for oxygen saturation were too varied to allow pooling of the results. Secondary analyses were performed on 4 outpatient trials of children with first-time wheezing, 7 trials in which only nebulized beta-agonists were used, and on all 15 trials identified. The results were similar, but the data varied more. CONCLUSION: Bronchodilators produce modest short-term improvement in clinical features of mild or moderately severe bronchiolitis.

Albuterol↗

PubMed1997

Tobacco and children. An economic evaluation of the medical effects of parental smoking.

OBJECTIVE: To determine the economic influence of pediatric disease attributable to parental smoking. DATA SOURCES: Computerized bibliographic databases were searched. Subject headings included asthma, burn, cost, low birth weight, otitis media, respiratory syncytial virus bronchiolitis, sudden infant death syndrome, and tobacco smoke pollution. The following constraints were applied to the published articles we studied: publication time, January 1980 through May 1996; age range of children studied, neonate to 18 years; and written in English. Articles used specifically as references for cost issues were limited to studies performed in the United States. DATA EXTRACTION: This study is a literature synthesis, which uses as its primary source the results of previously published best estimates. This is not a meta-analysis of studies analyzing the relationships between childhood disease and smoking. RESULTS: Using data for relative risk, prevalence, and cost of illness and death, we calculated the attributable risk fraction and corresponding direct medical expenditures and costs for loss of life. Costs are adjusted to 1993 dollars. Estimated annual excess cases of childhood illness and death attributable to parental smoking include low birth weight (46,000 cases, 2800 perinatal deaths), sudden infant death syndrome (2000 deaths), respiratory syncytial virus bronchiolitis (22,000 hospitalizations, 1100 deaths), acute otitis media (3.4 million outpatient visits), otitis media with effusion (110,000 tympanostomies), asthma (1.8 million outpatient visits, 14 deaths), and fire-related injuries (10,000 outpatient visits, 590 hospitalizations, and 250 deaths). CONCLUSIONS: Parental smoking is an important preventable cause of morbidity and mortality among American children; it results in annual direct medical expenditures of $4.6 billion and loss of life costs of $8.2 billion. Additional efforts to reduce children's exposure to tobacco smoke are warranted.

Burns↗

PubMed2005

Control group bias in randomized atypical antipsychotic medication trials for schizophrenia.

CONTEXT: It has been suggested that the need for concurrent placebo control groups in new schizophrenia studies might be minimized by making comparisons with external placebo. This strategy requires an assumption of constancy, that the novel medication will perform the same way in a study with only active controls as it would have in a placebo-controlled trial. OBJECTIVE: To test this constancy assumption in active- and low dose-controlled trials vs placebo-controlled trials of atypical antipsychotic medications. DATA SOURCES: A comprehensive search of bibliographic databases, conference proceedings, and Food and Drug Administration databases through November 24, 2003. STUDY SELECTION: English-language, randomized, double-blind clinical trials of newer atypical antipsychotic medications in otherwise unselected acutely ill adults with schizophrenia or schizoaffective disorder that reported baseline and intent-to-treat end point change values for the Brief Psychiatric Rating Scale. DATA EXTRACTION: Study number, sample size, reported dosage for each arm, trial duration, percentage of men, average age, trial arm treatment completion rate, baseline and within-arm end point change in the Brief Psychiatric Rating Scale, method of scoring the Brief Psychiatric Rating Scale, and date of publication were extracted from each study independently by 2 of us (S.W.W. and C.B.B.) each. DATA SYNTHESIS: There were 32 studies comprising 66 risperidone, olanzapine, quetiapine, and ziprasidone arms including 7264 patients. Random-effects analysis revealed that in atypical antipsychotic medication arms, the degree of improvement was nearly double in active-controlled trials than that seen with the same drugs and dosages in placebo-controlled studies. An effect of design was also observed in low dose-controlled studies vs placebo-controlled studies in ineffective and intermediate antipsychotic medication dose ranges. CONCLUSIONS: The observed control group bias indicates that the constancy assumption does not hold in recent antipsychotic medication trials. These results suggest that caution is indicated when considering active- or low dose-controlled studies requiring comparisons with external placebo as alternatives to placebo-controlled trials for establishing efficacy of new medications for schizophrenia.

Age Factors↗

PubMed1998

Effects of computer-based clinical decision support systems on physician performance and patient outcomes: a systematic review.

CONTEXT: Many computer software developers and vendors claim that their systems can directly improve clinical decisions. As for other health care interventions, such claims should be based on careful trials that assess their effects on clinical performance and, preferably, patient outcomes. OBJECTIVE: To systematically review controlled clinical trials assessing the effects of computer-based clinical decision support systems (CDSSs) on physician performance and patient outcomes. DATA SOURCES: We updated earlier reviews covering 1974 to 1992 by searching the MEDLINE, EMBASE, INSPEC, SCISEARCH, and the Cochrane Library bibliographic databases from 1992 to March 1998. Reference lists and conference proceedings were reviewed and evaluators of CDSSs were contacted. STUDY SELECTION: Studies were included if they involved the use of a CDSS in a clinical setting by a health care practitioner and assessed the effects of the system prospectively with a concurrent control. DATA EXTRACTION: The validity of each relevant study (scored from 0-10) was evaluated in duplicate. Data on setting, subjects, computer systems, and outcomes were abstracted and a power analysis was done on studies with negative findings. DATA SYNTHESIS: A total of 68 controlled trials met our criteria, 40 of which were published since 1992. Quality scores ranged from 2 to 10, with more recent trials rating higher (mean, 7.7) than earlier studies (mean, 6.4) (P<.001). Effects on physician performance were assessed in 65 studies and 43 found a benefit (66%). These included 9 of 15 studies on drug dosing systems, 1 of 5 studies on diagnostic aids, 14 of 19 preventive care systems, and 19 of 26 studies evaluating CDSSs for other medical care. Six of 14 studies assessing patient outcomes found a benefit. Of the remaining 8 studies, only 3 had a power of greater than 80% to detect a clinically important effect. CONCLUSIONS: Published studies of CDSSs are increasing rapidly, and their quality is improving. The CDSSs can enhance clinical performance for drug dosing, preventive care, and other aspects of medical care, but not convincingly for diagnosis. The effects of CDSSs on patient outcomes have been insufficiently studied.

Clinical Competence↗

PubMedDate not supplied

Empirical studies assessing the quality of health information for consumers on the world wide web: a systematic review.

CONTEXT: The quality of consumer health information on the World Wide Web is an important issue for medicine, but to date no systematic and comprehensive synthesis of the methods and evidence has been performed. OBJECTIVES: To establish a methodological framework on how quality on the Web is evaluated in practice, to determine the heterogeneity of the results and conclusions, and to compare the methodological rigor of these studies, to determine to what extent the conclusions depend on the methodology used, and to suggest future directions for research. DATA SOURCES: We searched MEDLINE and PREMEDLINE (1966 through September 2001), Science Citation Index (1997 through September 2001), Social Sciences Citation Index (1997 through September 2001), Arts and Humanities Citation Index (1997 through September 2001), LISA (1969 through July 2001), CINAHL (1982 through July 2001), PsychINFO (1988 through September 2001), EMBASE (1988 through June 2001), and SIGLE (1980 through June 2001). We also conducted hand searches, general Internet searches, and a personal bibliographic database search. STUDY SELECTION: We included published and unpublished empirical studies in any language in which investigators searched the Web systematically for specific health information, evaluated the quality of Web sites or pages, and reported quantitative results. We screened 7830 citations and retrieved 170 potentially eligible full articles. A total of 79 distinct studies met the inclusion criteria, evaluating 5941 health Web sites and 1329 Web pages, and reporting 408 evaluation results for 86 different quality criteria. DATA EXTRACTION: Two reviewers independently extracted study characteristics, medical domains, search strategies used, methods and criteria of quality assessment, results (percentage of sites or pages rated as inadequate pertaining to a quality criterion), and quality and rigor of study methods and reporting. DATA SYNTHESIS: Most frequently used quality criteria used include accuracy, completeness, readability, design, disclosures, and references provided. Fifty-five studies (70%) concluded that quality is a problem on the Web, 17 (22%) remained neutral, and 7 studies (9%) came to a positive conclusion. Positive studies scored significantly lower in search (P =.02) and evaluation (P =.04) methods. CONCLUSIONS: Due to differences in study methods and rigor, quality criteria, study population, and topic chosen, study results and conclusions on health-related Web sites vary widely. Operational definitions of quality criteria are needed.

Evaluation Studies as Topic↗

PubMed2002

Comparison of mortality between private for-profit and private not-for-profit hemodialysis centers: a systematic review and meta-analysis.

CONTEXT: Private for-profit and private not-for-profit dialysis facilities provide the majority of hemodialysis care in the United States. There has been extensive debate about whether the profit status of these facilities influences patient mortality. OBJECTIVE: To determine whether a difference in adjusted mortality rates exists between hemodialysis patients receiving care in private for-profit vs private not-for-profit dialysis centers. DATA SOURCES: We searched 11 bibliographic databases, reviewed our own files, and contacted experts in June 2001-January 2002. In June 2002, we also searched PubMed using the "related articles" feature, SciSearch, and the reference lists of all studies that fulfilled our eligibility criteria. STUDY SELECTION: We included published and unpublished observational studies that directly compared the mortality rates of hemodialysis patients in private for-profit and private not-for-profit dialysis centers and provided adjusted mortality rates. We masked the study results prior to determining study eligibility, and teams of 2 reviewers independently evaluated the eligibility of all studies. Eight observational studies that included more than 500 000 patient-years of data fulfilled our eligibility criteria. DATA EXTRACTION: Teams of 2 reviewers independently abstracted data on study characteristics, sampling method, data sources, and factors controlled for in the analyses. Reviewers resolved disagreements by consensus. DATA SYNTHESIS: The studies reported data from January 1, 1973, through December 31, 1997, and included a median of 1342 facilities per study. Six of the 8 studies showed a statistically significant increase in adjusted mortality in for-profit facilities, 1 showed a nonsignificant trend toward increased mortality in for-profit facilities, and 1 showed a nonsignificant trend toward decreased mortality in for-profit facilities. The pooled estimate, using a random-effects model, demonstrated that private for-profit dialysis centers were associated with an increased risk of death (relative risk, 1.08; 95% confidence interval, 1.04-1.13; P<.001). This relative risk suggests that there are annually 2500 (with a plausible range of 1200-4000) excessive premature deaths in US for-profit dialysis centers. CONCLUSIONS: Hemodialysis care in private not-for-profit centers is associated with a lower risk of mortality compared with care in private for-profit centers.

Health Services Research↗

PubMed2003

Long-term renal prognosis of diarrhea-associated hemolytic uremic syndrome: a systematic review, meta-analysis, and meta-regression.

CONTEXT: The long-term renal prognosis of patients with diarrhea-associated hemolytic uremic syndrome (HUS) remains controversial. OBJECTIVES: To quantify the long-term renal prognosis of patients with diarrhea-associated HUS and to identify reasons for different estimates provided in the literature. DATA SOURCES: We searched MEDLINE and Experta Medica (EMBASE) bibliographic databases and conference proceedings, and we contacted experts until February 2003. We also searched the Institute for Scientific Information index and reference lists of all studies that fulfilled our eligibility criteria. The search strategy included the terms hemolytic-uremic syndrome, purpura, thrombotic thrombocytopenic, Escherichia coli O157, longitudinal studies, kidney diseases, hypertension, and proteinuria STUDY SELECTION: Any study that followed up 10 or more patients with primary diarrhea-associated HUS for at least 1 year for renal sequelae. DATA EXTRACTION: Two authors independently abstracted data on study and patient characteristics, renal measures, outcomes, and prognostic features. Disagreements were resolved by a third author or by consensus. DATA SYNTHESIS: Forty-nine studies of 3476 patients with a mean follow-up of 4.4 years (range, 1-22 years at last follow-up) from 18 countries, 1950 to 2001, were summarized. At the time of recruitment, patients were aged 1 month to 18 years. In the different studies, death or permanent end-stage renal disease (ESRD) ranged from 0% to 30%, with a pooled incidence of 12% (95% confidence interval [CI], 10%-15%). A glomerular filtration rate lower than 80 mL/min per 1.73 m2, hypertension, or proteinuria was extremely variable and ranged from 0% to 64%, with a pooled incidence of 25% (95% CI, 20%-30%). A higher severity of acute illness was strongly associated with worse long-term prognosis. Studies with a higher proportion of patients with central nervous system symptoms (coma, seizures, or stroke) had a higher proportion of patients who died or developed permanent ESRD at follow-up (explaining 44% of the between-study variability, P =.01). Studies with a greater proportion of patients lost to follow-up also described a worse prognosis (P =.001) because these patients were typically healthier than those followed up. One or more years after diarrhea-associated HUS, patients with a predicted creatinine clearance higher than 80 mL/min per 1.73 m2, no overt proteinuria, and no hypertension appeared to have an excellent prognosis. CONCLUSIONS: Death or ESRD occurs in about 12% of patients with diarrhea-associated HUS, and 25% of survivors demonstrate long-term renal sequelae. Patients lost to follow-up contribute to worse estimates in some studies. The severity of acute illness, particularly central nervous system symptoms and the need for initial dialysis, is strongly associated with a worse long-term prognosis.

Diarrhea↗

PubMed2004

Highly active antiretroviral therapy and sexual risk behavior: a meta-analytic review.

CONTEXT: Evidence suggests that since highly active antiretroviral therapy (HAART) became available, the prevalence of unprotected sex and the incidence of sexually transmitted infections (STIs) have increased. OBJECTIVE: To conduct 3 meta-analyses to determine whether (1) being treated with HAART, (2) having an undetectable viral load, or (3) holding specific beliefs about HAART and viral load are associated with increased likelihood of engaging in unprotected sex. DATA SOURCES: A comprehensive search included electronic bibliographic databases, including AIDSLINE, MEDLINE, PubMed, CINHAL, PsycInfo, ERIC, EMBASE, and Sociofile, from January 1996 to August 2003, conference proceedings, hand searches of journals, reference lists of articles, and contacts with researchers. STUDY SELECTION: Twenty-five English-language studies (some contributing >1 finding) met the selection criteria and examined the association of unprotected sexual intercourse or STIs with receiving HAART (21 findings), having an undetectable viral load (13 findings), or beliefs about HAART and viral load (18 findings). DATA EXTRACTION: Reports were screened and information from eligible studies was abstracted independently by pairs of reviewers using a standardized spreadsheet. DATA SYNTHESIS: Random-effects models were used to aggregate data. The prevalence of unprotected sex was not higher among persons with the human immunodeficiency virus (HIV) receiving HAART (prevalence range, 9%-56%; median, 33%) vs those not receiving HAART (range, 11%-77%; median, 44%; odds ratio [OR], 0.92; 95% confidence interval [CI], 0.65-1.31) or among HIV-positive persons with an undetectable viral load (range, 10%-68%; median, 39%) vs those with a detectable viral load (range, 14%-70%; median, 42%; OR, 0.99; 95% CI, 0.82-1.21). The prevalence of unprotected sex was elevated (OR, 1.82; 95% CI, 1.52-2.17) in HIV-positive, HIV-negative, and unknown serostatus persons who believed that receiving HAART or having an undetectable viral load protects against transmitting HIV or who had reduced concerns about engaging in unsafe sex given the availability of HAART (range, 17%-81% [median, 49%] vs 9%-68% [median, 38%] for counterparts). CONCLUSIONS: In the studies reviewed, HIV-positive patients receiving HAART did not exhibit increased sexual risk behavior, even when therapy achieved an undetectable viral load. However, people's beliefs about HAART and viral load may promote unprotected sex and may be amenable to change through prevention messages.

Antiretroviral Therapy, Highly Active↗

PubMed1998

Expanding yeast knowledge online.

The completion of the Saccharomyces cerevisiae genome sequencing project and the continued development of improved technology for large-scale genome analysis have led to tremendous growth in the amount of new yeast genetics and molecular biology data. Efficient organization, presentation, and dissemination of this information are essential if researchers are to exploit this knowledge. In addition, the development of tools that provide efficient analysis of this information and link it with pertinent information from other systems is becoming increasingly important at a time when the complete genome sequences of other organisms are becoming available. The aim of this review is to familiarize biologists with the type of data resources currently available on the World Wide Web (WWW).

Amino Acid Sequence↗

PubMed1990

A mathematical model of retrieval system performance.

There have been a number of major evaluations of the performance of retrieval systems against large full text and surrogate (bibliographic) databases. These evaluations have concentrated on the experimental determination of the Precision Ratio, the fraction of retrieved items that are relevant to an information request, and the Recall Ratio, the fraction of the total number of relevant items that were actually retrieved. While these measures have met with general acceptance, they have also generated much controversy. The purpose of this article is to review the results of several of the largest evaluations and to propose a simple model for the performance of such systems that may help explain the relationship between these measures and user behavior.

Evaluation Studies as Topic↗