Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Standardization”

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.

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

At least 1,477 records · Page 82Linked to original sources
PubMed1997

Comparison of COBE white cell-reduction and standard plateletpheresis protocols in the same donors.

BACKGROUND: It is necessary to protect patients from white cell (WBC)-caused side effects of platelet transfusion by reducing the WBC contamination in single-donor platelets. STUDY DESIGN AND METHODS: A new COBE Spectra WBC (leuko)-reduction system (LRS) was compared to the COBE standard plateletpheresis (standard) procedure. Each of 62 donors underwent plateletpheresis under the two protocols (LRS and standard). The collection efficiency and WBC contamination in the components collected using the techniques were compared. Platelets were counted in a cell counter and WBCs were counted using two full grids of a Nageotte chamber. RESULTS: The preseparation and postseparation numbers for red cells, WBCs, and platelets as well as the number of collected platelets were not different in the two techniques. Collection efficiency in the LRS procedures was 96.2 +/- 13.0 percent of that in the standard procedures. Median WBC contamination in the platelet components was 10,160 per LRS procedure and 56,500 per standard procedure. The purity of the LRS components was significantly improved (p = 0.001), as seen in a comparison of the WBC numbers in components per procedure after log10 transformation (LRS: 0.096 +/- 0.195 x 10(6); standard: 0.390 +/- 1.075 x 10(6)). CONCLUSION: These data suggest that the LRS procedure produces platelet concentrates with a collection efficiency that is comparable to that obtained with the standard technique and with a residual WBC content that satisfies even the most stringent criteria for filtered platelets. As this purity can be achieved without platelet loss or alteration, conventional fiber filtration no longer seems necessary or useful in this type of single-donor platelet component.

Blood Donors↗
PubMed2001

[Value of selective MIP reconstructions in respiratory triggered 3D TSE MR-cholangiography on a workstation in comparison with MIP standard projections and single-shot MRCP].

PURPOSE: Comparison of anatomical visualisation and diagnostic value of selective MIP reconstructions of respiratory triggered 3D-TSE-MRCP versus standard MIP reconstructions and single-shot MRCP. MATERIAL AND METHODS: 50 patients with pancreaticobiliary disease were examined at 1.5 Tesla (ACS NT II, Philips Medical Systems) using a breath-hold single-shot (SS) and a respiratory triggered 3D-TSE-MRCP technique in 12 standard MIP projections. Additional selective MIP reconstructions with different slice thickness (2, 4, 10 cm) and projections were performed on a workstation. Visualization of the pancreaticobiliary system and the diagnostic value of the examinations were analysed. RESULTS: Single-shot and 3D-TSE in standard projections showed comparable anatomical visualisation. On selective MIP reconstructions the biliary system (SS p < 0.002; 3D-TSE p < 0.000) and the periampullary region (SS p < 0.000; 3D-TSE p < 0.003) were more clearly seen than on SS and standard MIP reconstructions. Furthermore, superior visualisation of the pancreatic duct could be achieved with additional selective MIP reconstructions in contrast to standard MIP (p < 0.003). Sensitivity and diagnostic accuracy showed superior results for selective and standard MIP reconstructions, but no significant differences between the three techniques were found. CONCLUSION: SS and standard MIP reconstructions showed comparable anatomical visualisation. Selective MIP postprocessing on a workstation offers a better visualisation of the pancreaticobiliary system and is useful for detecting pathological alterations.

Artifacts↗
PubMed2004

[Standardizing the radiologic report -- norm DIN 6827-5].

PURPOSE: According to the current German "Rules and Regulation for the Application of X-rays" (RöV), a radiological report has to be issued whenever a person undergoes an examination involving x-rays. Since the RöV is not specific as to its contents, the German Radiology Standards Committee (NAR) has developed a standard for the reports. The scope of this reporting standard was expanded beyond x-ray procedures to all imaging modalities. MATERIALS AND METHODS: The radiologic report describes the type of examination performed on the patient. Following the "DICOM Structured Report" information model, the report is structured in form of a document tree. The report must be archived in printed form or digitally. RESULTS: The report is thematically divided into six sections. Within each section, the data are condensed to the smallest still meaningful information unit. For each entry, it is stated whether it is obligatory or optional. CONCLUSION: The reports according to the standards of the NAR comply with the RöV. Standards prescribing a structure can be used as guide for uniform reporting, as appropriate for printed reports. By consistently following the DICOM standards, future international standards for medical contents can be integrated into radiologic reports.

Germany↗
PubMed2005

The keyhole concept in aneurysm surgery--a comparative study: keyhole versus standard craniotomy.

OBJECTIVE: The purpose of the study is to compare the results of minimally invasive keyhole craniotomy and standard larger craniotomies in the surgical treatment of patients with intracranial aneurysms. METHODS: In the past eight years 628 patients were operated by two experienced neurosurgical teams. The first group of 482 patients with 565 aneurysms were operated through a small keyhole craniotomy, using the eyebrow keyhole approach in particular. The remaining 146 patients with 167 aneurysms were operated using a standard craniotomy that included pterional/frontotemporal, frontoparietal parasagittal, and retrosigmoid suboccipital craniotomies. All operations were performed in the standard microsurgical technique using intraoperative evoked potential monitoring and endoscopic assistance in selected cases. RESULTS: Most supratentorial aneurysms and basilar tip aneurysms were successfully operated through an eyebrow keyhole craniotomy. Distal MCA aneurysms as well as aneurysms on the MCA with a long M1 segment were operated through a temporal keyhole, and aneurysms of the distal PCA (P2-P3) segment subtemporally. The frontoparietal parasagittal keyhole approach was used only for pericallosal artery aneurysms. Infratentorial aneurysms of the VA/PICA complex were operated via a retrosigmoid approach. On comparing the surgery results in patients with a keyhole craniotomy and those with standard craniotomy, similar outcomes were found for both groups, with excellent or very good outcomes (GOS 5 and 4) in 398 (82.57%) patients from the keyhole craniotomy group, and in 116 (79.45%) patients from the standard craniotomy group. The mortality rate in the keyhole group was 0.83% (4 patients) and 2.05% (3 patients) in the standard craniotomy group. CONCLUSION: Parallel treatment results in using two options--keyhole craniotomy and standard larger craniotomy--were analysed in the past eight years. Two experienced neurosurgical teams in performing both surgical approaches have reached almost similar morbidity and mortality rates, and overall surgical results. The type of craniotomy is selected according to the experience of the surgical team, and familiarity with certain approach. The authors have good experience with the minimally invasive approach for different intracranial pathology and recommend it especially in neurovascular surgery.

Adolescent↗
PubMed1992

A comparison of standard-dose and high-dose epinephrine in cardiac arrest outside the hospital. The Multicenter High-Dose Epinephrine Study Group.

BACKGROUND: Experimental and uncontrolled clinical evidence suggests that intravenous epinephrine in doses higher than currently recommended may improve outcome after cardiac arrest. We conducted a prospective, multicenter study comparing standard-dose epinephrine with high-dose epinephrine in the management of cardiac arrest outside the hospital. METHODS: Adult patients were enrolled in the study if they remained in ventricular fibrillation, or if they had asystole or electromechanical dissociation, at the time the first drug was to be administered to treat the cardiac arrest. Patients were randomly assigned to receive either 0.02 mg of epinephrine per kilogram of body weight (standard-dose group, 632 patients) or 0.2 mg per kilogram (high-dose group, 648 patients), both given intravenously. RESULTS: In the standard-dose group 190 patients (30 percent) had a return of spontaneous circulation, as compared with 217 patients (33 percent) in the high-dose group; 136 patients (22 percent) in the standard-dose group and 145 patients (22 percent) in the high-dose group survived to be admitted to the hospital. Twenty-six patients (4 percent) in the standard-dose group and 31 (5 percent) in the high-dose group survived to discharge from the hospital. Ninety-two percent of the patients discharged in the standard-dose group and 94 percent in the high-dose group were conscious at the time of hospital discharge. None of the differences in outcome between the groups were statistically significant. CONCLUSIONS: In this study, we were unable to demonstrate any difference in the overall rate of return of spontaneous circulation, survival to hospital admission, survival to hospital discharge, or neurologic outcome between patients treated with a standard dose of epinephrine and those treated with a high dose.

Aged↗
PubMed1997

Low-dose compared with standard-dose m-BACOD chemotherapy for non-Hodgkin's lymphoma associated with human immunodeficiency virus infection. National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group.

BACKGROUND: Reduced doses of cytotoxic chemotherapy or standard-dose therapy plus a myeloid colony-stimulating factor decreases hematologic toxicity and its complications in patients with non-Hodgkin's lymphoma associated with infection with the human immunodeficiency virus (HIV). However, the effect of reducing the doses of cytotoxic chemotherapeutic agents on clinical outcome is not known. METHODS: We randomly assigned 198 HIV-seropositive patients with previously untreated, aggressive non-Hodgkin's lymphoma to receive standard-dose therapy with methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) along with granulocyte-macrophage colony-stimulating factor (GM-CSF; n=94) or reduced-dose m-BACOD with GM-CSF administered only as indicated (n=98). RESULTS: A complete response was achieved in 39 of the 94 assessable patients assigned to low-dose therapy (41 percent) and in 42 of the 81 assessable patients assigned to standard-dose therapy (52 percent, P= 0.56). There were no significant differences in overall or disease-free survival; median survival times were 35 weeks for patients receiving low-dose therapy and 31 weeks for those receiving standard-dose therapy (risk ratio for death in the standard-dose group=1.17; 95 percent confidence interval, 0.84 to 1.63; P=0.25). Toxic effects of chemotherapy rated grade 3 or higher occurred in 66 of 94 patients assigned to standard-dose therapy (70 percent) and 50 of 98 patients assigned to low-dose treatment (51 percent, P=0.008). Hematologic toxicity accounted for the difference. CONCLUSIONS: As compared with treatment with standard doses of cytotoxic chemotherapy (m-BACOD), reduced doses caused significantly fewer hematologic toxic effects yet had similar efficacy in patients with HIV-related lymphoma. Dose-modified chemotherapy should be considered for most HIV-infected patients with lymphoma.

Adult↗
PubMed2003

Addition of ifosfamide and etoposide to standard chemotherapy for Ewing's sarcoma and primitive neuroectodermal tumor of bone.

BACKGROUND: Ewing's sarcoma and primitive neuroectodermal tumor of bone are closely related, highly malignant tumors of children, adolescents, and young adults. A new drug combination, ifosfamide and etoposide, was highly effective in patients with Ewing's sarcoma or primitive neuroectodermal tumor of bone who had a relapse after standard therapy. We designed a study to test whether the addition of these drugs to a standard regimen would improve the survival of patients with newly diagnosed disease. METHODS: Patients 30 years old or younger with Ewing's sarcoma, primitive neuroectodermal tumor of bone, or primitive sarcoma of bone were eligible. The patients were randomly assigned to receive 49 weeks of standard chemotherapy with doxorubicin, vincristine, cyclophosphamide, and dactinomycin or experimental therapy with these four drugs alternating with courses of ifosfamide and etoposide. RESULTS: A total of 518 patients met the eligibility requirements. Of 120 patients with metastatic disease, 62 were randomly assigned to the standard-therapy group and 58 to the experimental-therapy group. There was no significant difference in five-year event-free survival between the treatment groups (P=0.81). Among the 398 patients with nonmetastatic disease, the mean (+/-SE) five-year event-free survival among the 198 patients in the experimental-therapy group was 69+/-3 percent, as compared with 54+/-4 percent among the 200 patients in the standard-therapy group (P=0.005). Overall survival was also significantly better among patients in the experimental-therapy group (72+/-3.4 percent vs. 61+/-3.6 percent in the standard-therapy group, P=0.01). CONCLUSIONS: The addition of ifosfamide and etoposide to a standard regimen does not affect the outcome for patients with metastatic disease, but it significantly improves the outcome for patients with nonmetastatic Ewing's sarcoma, primitive neuroectodermal tumor of bone, or primitive sarcoma of bone.

Adolescent↗
PubMed2001

Clinical evaluation of St Jude Medical Hemodynamic Plus versus standard aortic valve prostheses: The Italian multicenter, prospective, randomized study.

OBJECTIVE: Hemodynamic and clinical performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus aortic valves (St Jude Medical, Inc, St Paul, Minn) were compared with those of 21-mm and 23-mm St Jude Medical standard cuff aortic valves in the first such multicenter, prospective, randomized study. Hemodynamic Plus valves are mechanical, bileaflet prostheses suitable for the small aortic anulus. METHODS: Patients with 21-mm and 23-mm anulus diameters were randomized to receive either a Hemodynamic Plus or a standard cuff valve. Postoperatively and at 6 months after the operation, patients underwent 2-dimensional Doppler echocardiography. Ejection fraction, cardiac output, peak gradient, mean gradient, effective orifice area, effective area index, and performance index were calculated. Postoperative and 6-month echocardiographic measurements and their variations across observation times were analyzed statistically. RESULTS: Of the 140 patients enrolled, 5 died at operation and 1 died of aortic dissection during the follow-up period. Eight patients were lost to follow-up. A total of 125 patients completed the study. In 1 patient a sewing cuff escaped intraoperatively. At 6 months the 21-mm and 23-mm Hemodynamic Plus valves showed significantly lower peak gradients and mean gradients than those of the 21-mm and 23-mm standard cuff valves. The 21-mm Hemodynamic Plus valves had gradients similar to those of the 23-mm Hemodynamic Plus valves. The effective orifice area did not differ significantly between the Hemodynamic Plus and standard cuff valves at either measurement. No valve mismatch was found in the 4 groups of patients. A more enhanced decrease of peak gradients and mean gradients and a more enhanced increase of effective orifice areas, effective area indices, and performance indices were found across observation times for patients with Hemodynamic Plus valves compared with those with standard cuff valves. CONCLUSIONS: Clinical hemodynamic performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus valves correspond closely with those of standard cuff valves, and gradients are substantially better than those of standard cuff valves of the same diameter. Therefore, use of this valve may minimize the need for aortic anulus enlargement. Early follow-up results with the Hemodynamic Plus valves were excellent, although more time is required to confirm this outcome.

Aortic Valve↗
PubMed1998

Secular changes in standards of bodily attractiveness in American women: different masculine and feminine ideals.

Silverstein, Peterson, and Perdue (1986) studied changes in curvaceousness of the models in Vogue magazine over time and found that curvaceousness was inversely correlated with American women's participation in higher education and the professions. In the present study, it was predicted that the male standard for women's bodily attractiveness would differ from the female standard and would change differently over time, based on evolutionary theory. Published data on the bodily curvaceousness of models in Playboy and Vogue and on Miss America winners were used to test this hypothesis. Although they did not differ on average, the male and female standards changed differently over time. There was less variation in the male standard, represented by Playboy and by Miss America winners, than in the female standard, represented by Vogue. Results suggest that cultural standards of attractiveness are influenced by an evolved psychology of mate selection that has implications for understanding changes in the standard of attractiveness and its relation to eating disorders.

Adult↗
PubMedDate not supplied

The development of European standard (CEN) methods in support of European Directives for plastics materials and articles intended to come into contact with foodstuff.

CEC Directives have been implemented for plastics materials and articles intended to come into contact with foodstuffs. These introduce limits upon the overall migration from plastics into food and food simulants. In addition, specific migration limits or composition limits for free monomer in the final article, have been set for some monomers. Agreed test methods are required to allow these Directives to be respected. CEN, the European Committee for Standardization, has created a working group to develop suitable test methods. This is 'Working Group 5, Chemical Methods of Test', of CEN Technical Committee TC 194, Utensils in contact with food. This group has drafted a ten part standard for determining overall migration into aqueous and fatty food simulants by total immersion, by standard cell, by standard pouch and by filling. This draft standard has been approved by CEN TC 194 for circulation for public comment as a provisional standard, i.e. as an ENV. Further parts of this standard are in preparation for determining overall migration at high temperatures, etc. Simultaneously, Working Group 5 is cooperating with the BCR (Community Bureau of Reference) to produce reference materials with certified values of overall migration. CEN TC 194 Working Group 5 is also drafting methods for monomers subject to limitation in Directive 90/128/EEC. Good progress is being made on the monomers of highest priority but it is recognized that developing methods for all the monomers subject to limitation would take many years. Therefore, collaboration with the BCR, the Council of Europe and others is taking place to accelerate method development.

Animals↗
PubMed1999

Doxazosin GITS compared with doxazosin standard and placebo in patients with mild hypertension.

Doxazosin, an effective treatment for mild-to-moderate hypertension and benign prostatic hyperplasia, in its standard formulation requires a multiple-step titration regimen to minimize the potential for first-dose effects. A new controlled-release gastrointestinal therapeutic system (GITS) formulation of doxazosin was developed to enhance the pharmacokinetic profile, significantly reducing serum peak-to-trough ratios, thereby minimizing the need for titration. We assessed the efficacy and tolerability of doxazosin GITS compared with doxazosin standard and placebo in a prospective, randomized, double-blind, parallel-group, dose-titration, multicenter study of 392 patients with mild hypertension (blood pressure [BP] < or = 180/95-105 mmHg). Patients were randomized to doxazosin GITS, doxazosin standard, or placebo in 2:2:1 manner. The primary outcome measure was the proportion of patients in the per-protocol analysis (PPA) who achieved goal BP response (sitting BP < or = 90 mmg or 10 mmHg decrease from baseline at 24 h postdose at the final evaluable visit). Goal BP response in the intention-to-treat (ITT) population and prespecified BP and/or heart rate changes in the PPA and/or ITT population were also analyzed. Tolerability was assessed throughout the study. Doxazosin GITS and doxazosin standard produced comparable goal BP responses superior to that of placebo, with 92 of 156 patients (59.0%) on doxazosin GITS and 86 of 152 patients (56.6%) on doxazosin standard in the PPA population achieving goal BP response 24 hours postdose on the final visit, compared with 25 of 70 patients (35.7%) on placebo. Both active treatments produced mean significant BP reductions compared with baseline and placebo (p < 0.001). The most commonly reported side effects were headache, dizziness, and asthenia. No syncope was reported in the doxazosin GITS group; two cases were observed in the doxazosin standard group and one case in the placebo group. Doxazosin GITS was well tolerated and as effective as doxazosin standard in patients with mild hypertension, producing well-tolerated, comparable BP reductions with minimal need for titration. Both active treatments were clinically and statistically superior to placebo.

Adult↗
PubMed1999

Participative versus assigned production standard setting in a repetitive industrial task: a strategy for improving worker productivity.

The participative standard with feedback condition was superior to the assigned difficult (140% of normal) standard with feedback condition in terms of worker productivity. The percentage increase in worker productivity with the participative standard and feedback condition was 46%, whereas the increase in the assigned difficult standard with feedback was 23%, compared to the control group (no standard, no feedback). Worker productivity also improved significantly as a result of assigning a normal (100%) production standard with feedback, compared to the control group, and the increase was 12%. The participative standard with feedback condition emerges as the optimum strategy for improving worker productivity in a repetitive industrial production task.

Efficiency↗
PubMed2005

National Occupational Standards in clinical embryology: implementation in 2005?

In 2001 the UK Department of Health initiated the National Occupational Standards Project in Healthcare Science. This project incorporates the 43 disciplines of healthcare science with the aim of developing a framework for competent performance in all areas of healthcare science, thereby standardising the delivery of services in this area. The whole of the project relies on the concept of function, and using the process of functional analysis each discipline is broken down into key work areas. The standards are derived from a further breakdown of these key work areas. Each standard gives expected requirements for the competent performance of the function, along with the relevant knowledge required. It is envisaged that the implementation of National Occupational Standards will ensure that individuals performing healthcare science functions throughout the UK, whether they are healthcare scientists themselves or not, will be performing these functions to an adequate standard. Since work began on the project 63 standards, and associated assessment guidance, have been drafted the whole of healthcare science. The National Occupational Standards are due to be implemented in 2005 by Skills for Health, an organisation that defines and monitors skills in healthcare both in the NHS and the private sector.

Humans↗
PubMed1983

Critical review of international standards for respiratory protective equipment - I. Respiratory protective equipment for particulate-laden atmospheres.

The standards for respiratory protective equipment (R.P.E.) from eleven countries and standards organizations were grouped according to type as particulate removing, gas and vapor removing, airline (fresh air hose and compressed air types), and self-contained breathing apparatus (open circuit and closed circuit). Each group of standards was further divided into specification and performance requirements. This paper is one in a series of three that highlights and critically reviews international respirator standards; it deals specifically with R.P.E. for protection against particulate-laden atmospheres. Great Britain, Australia, European Committee for Standardization (CEN), France, South Africa, Italy, Spain, New Zealand, Scandinavia, Japan, and Germany have standards for R.P.E. against particulate-laden atmospheres. Tabular summaries and accompanying discussion of national requirements are presented in the following categories: solid and liquid aerosol removal efficiency, clogging, and rough usage. Large differences and some notable omissions exist among standards. For example, the protection capacity of the filter can be tested by using solid particulate or liquid challenge aerosols. The majority of the countries evaluate protection capacity using solid particulate aerosols, while the remainder use both solid and liquid or liquid aerosols only. Other differences in filter testing deal with the composition of the test aerosol and the characteristic of the filter measured. The initial penetration or the penetration of the filter as it is being loaded over a specified period of time can be measured. In the latter case penetration is averaged over the test period and the degree of protection is assessed only for that overall time period; information is not provided concerning the protection afforded by the filter in the earlier stages of use.

Aerosols↗
PubMed2005

Guidelines for standardization of radiostereometry (RSA) of implants.

There is a need for standardization of radiostereometric (RSA) investigations to facilitate comparison of outcome reported from different research groups. In this document, 6 research centers have agreed upon standards for terminology, description and use of RSA arrangement including radiographic set-up and techniques. Consensus regarding minimum requirements for marker stability and scatter, choice of coordinate systems, and preferred way of describing prosthetic micromotion is of special interest. Some notes on data interpretation are also presented. Validation of RSA should be standardized by preparation of protocols for assessment of accuracy and precision. Practical issues related to loading of the joint by weight bearing or other conditions, follow-up intervals, length of follow-up, radiation dose, and the exclusion of patients due to technical errors are considered. Finally, we present a checklist of standardized output that should be included in any clinical RSA paper.This document will form the basis of a detailed standardization protocol under supervision of ISO and the European Standards Working Group on Joint Replacement Implants (CEN/TC 285/WG4). This protocol will facilitate inclusion of RSA in a standard protocol for implant testing before it is released for general use. Such a protocol-also including other recognized clinical outcome parameters-will reduce the risk of implanting potentially inferior prostheses on a large scale.

Arthroplasty, Replacement, Hip↗
PubMed2001

Comparison of dosimetric standards of Canada and France for photons at 60Co and higher energies.

We report the results of a comparison of the dosimetric standards of Canada and France for photon beams at 60Co and a few higher energies. The present primary standard of absorbed dose to water for NRC, Canada is based on measurements made with a sealed water calorimeter. The corresponding standard of the LNHB, France is based on measurements made with a graphite calorimeter at 60Co energy and transferred to absorbed dose to water for 60Co and higher-energy photon beams using both ion chambers and Fricke dosemeters as transfer instruments. To make this comparison, we used three graphite-walled NE2571 Farmer chambers. The absorbed dose to water determined by the LNHB was greater than that determined by NRC by 0.20% at 60Co energy. This difference is not significant given the uncertainties on the standards. In order to do the comparison for higher-energy photons, we interpolated the NRC data set at the beam qualities used at the LNHB. When %dd(10)x is used as the method of specifying beam quality, the determination of absorbed dose to water by the LNHB is about 0.2% greater than that determined by NRC and consistent with the results at 60Co. However, when using TPR20,10 as the beam quality specifier, the LNHB determination is greater than the NRC's determination by 0.8% and 1.2% at 12 and 20 MV respectively. This discrepancy, which systematically increases with increasing energy, eventually exceeds the uncertainties in the ratio of the standards, estimated to be 0.7%. This underscores the importance of selecting the method of specifying beam quality, either %dd(10)x or TPR20,10, at least for the 'soft' beams used by NRC in this comparison. In the case of the air kerma standards, which were also compared at 60Co energy, the LNHB determination was greater than NRC's by 0.14%, which is not significant given the uncertainties on the standards.

Calorimetry↗
PubMed2006

Data standards: a call to action.

Access to data is something that every molecular biologist takes for granted nowadays, but data alone is of little use unless it is made available in a useable form through the development and global uptake of data standards. The challenge of standards development has been taken up by grass-roots movements working within several different branches of the biomedical research community. Many of these initiatives are proving extremely successful; for example, the Gene Ontology, which provides a controlled vocabulary for describing the properties of gene products, the Microarray Gene Expression Data Society's standards for describing microarray experiments, and the emerging standards developed by the Proteomics Standards Initiative are gaining broad acceptance. Standards development now faces its greatest ever challenge--the integration of diverse data types to fulfill the goals of systems biology. Now is the time for the communities that are developing these standards, the funding bodies that have invested so heavily in high-throughput data generation, and the publishers of biomedical research papers to cooperate fully to make the goals of integrated data analysis a reality.

Animals↗
PubMed2005

Substantial overestimation of standard errors of relative survival rates of cancer patients.

Relative survival rates are among the most commonly reported outcome measures of cancer patients. They are calculated as ratios of observed survival rates and the expected survival rates in the absence of cancer. Standard errors of relative survival rates are commonly calculated by dividing the standard error for absolute survival rates by the expected survival, without taking possible random variation of the latter into account. The aim of this study was to empirically assess the validity of these commonly reported standard errors. Using data from the nationwide Finnish Cancer Registry, the authors calculated 5- and 10-year absolute, expected, and relative survival rates for patients with 25 common forms of cancer in Finland in 1989. The authors used bootstrap analysis to empirically assess the random error of absolute and relative survival rates and then compared the results with conventionally derived estimates of standard errors. The conventional and bootstrap standard errors were closely similar for all estimates of absolute survival. By contrast, the conventional estimates of standard errors of 5- and 10-year relative survival exceeded the bootstrap estimates by up to 17% and 32%, respectively. The authors conclude that conventional derivation may substantially overestimate standard errors for relative survival.

Age Distribution↗