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PubMed1994

Foundations of hand-transmitted vibration standards.

Standards for hand-transmitted vibration predict dependent variables (e.g. finger blanching) from measurements of a few independent variables (e.g. vibration magnitude, vibration frequency, exposure duration). This paper illustrates the assumptions in the current International Standard guidelines for the evaluation of hand-transmitted vibration and compares research methods which may provide information to improve the guidance. Subjective assessments of vibration discomfort have influenced the frequency weighting used in current standards, but the data have been modified greatly for this purpose. Subjective and biodynamic data suggest that the severity of vibration may not be similar for vibration occurring in different axes. Physiological and pathological studies seek to uncover the mechanisms involved in the temporary and permanent changes caused by vibration, but they have yet to contribute to the guidance in standards. Future experimental studies in humans are unlikely to be sufficient to determine how injury depends on the characteristics of vibration exposures at work. Epidemiological studies are required to uncover the effects of occupational exposures, but the complexity of occupational exposures will prevent the formulation of standards based solely on the results of epidemiological studies. Standards for hand-transmitted vibration include unproven assumptions but, for those assessing the severity of occupational exposures, they offer the most reasonable method for predicting the likely effects of vibration. A combination of subjective, biodynamic, physiological, pathological and epidemiological studies is required to improve current guidance.

Hand↗
PubMed1995

[Comparative study of diagnostic standards of eye-signs in blood stasis syndrome and of blood stasis syndrome].

By virtue of a diagnostic study of 781 cases on the basis of six standards, it was shown that for the effectiveness in diagnostic positive rate, sensitivity, specificity, false positive rate, false negative rate and comprehensive scoring, the International Diagnostic Standards for Blood Stasis Syndrome (BSS) and Chinese Diagnostic Standards for BSS were the best ones, BSS Eye-Signs and Japanese BSS Diagnostic Standards were the second, trial program of International Stasis Diagnostic Standards and Zhongshan's BSS tenderness points came the third. Each standard has its unique advantage and therefore, we should take the other's advantage to offset one's weakness. The causes of their weakness have been discussed and the rational recommendation for their application has been proposed.

Blood Viscosity↗
PubMed1996

The international standard for plasminogen activator inhibitor-1 (PAI-1) activity.

Since the finding that plasminogen activator inhibitor-1 (PAI-1) may influence the initiation and progression of acute myocardial infarction, the assay of PAI-1 in plasma using a variety of commercial kits has become commonplace. The need for a standard to define the activity of PAI-1 prompted an international collaborative study (ICS) to calibrate the functional potency of a lyophilised plasma PAI-1 preparation (92/654). Since PAI-1 inhibits the 2 major plasminogen activators, tissue-type plasminogen activator (t-PA) and urinary-type plasminogen activator (u-PA) in an equimolar manner it was important to establish the potency of the PAI-1 inhibitor in terms of both t-PA and u-PA neutralisation. While the ICS indicated a wide spread of data between the laboratories the mean value of 27.5 t-PA neutralisation units and 7.0 u-PA neutralisation units was confirmed by numerous assays at NIBSC using a tedious but technically reliable titration assay procedure. The plasma PAI-1 proposed standard (92/654) was stable at 20 degrees C for 20 months. The Fibrinolysis Subcommittee of the Scientific and Standardization Committee (SSC) of the International Society on Thrombosis and Haemostasis (ISTH), (meeting in Leuven. Belgium in September 1994) has recommended that the plasma PAI-1 (92/654) should be accepted as the International Standard for PAI-1 and should define a unitage in terms of both t-PA and u-PA neutralisation. Subsequently the Expert Committee on Biological Standardization of the World Health Organization (ECBS-WHO) meeting in Geneva, Switzerland in October 1995 approved plasma PAI-1 (92/654) as the International Standard.

Humans↗
PubMed1997

Calibration of Abbott AxSYM Ferritin kit using the WHO Human Liver Ferritin International Standard 80/602.

A commercial ferritin kit (Abbott AxSYM Ferritin) was calibrated using the WHO Human Liver Ferritin International Standard 80/602. The reconstituted WHO freeze-dried standard was diluted to obtain six concentration levels ranging from 10-840 micrograms/l. In the analysis of the data, logarithmic transformation of the results was performed in order to stabilize the variance. The AxSYM kit yielded slightly higher values than the WHO Ferritin Standard (p < 0.05). The relation between the AxSYM kit and the WHO Ferritin Standard (untransformed values) was described by a proportionality: FerritinAxSYM = 1.057 x FerritinWHO. WHO Ferritin Standard values of 12 and 15 micrograms/l (used as cut-off values for absent or small body iron reserves) yielded calculated AxSYM values of 12.7 and 15.9 micrograms/l. A WHO Ferritin Standard value of 30 micrograms/l (used threshold value for the presence of stainable bone marrow haemosiderin iron) yielded a calculated AxSYM value of 31.7 micrograms/l.

Calibration↗
PubMed1998

Failure of standard magnetic resonance imaging in patients with refractory temporal lobe epilepsy.

OBJECTIVE: To compare the sensitivity of standard magnetic resonance imaging (MRI) scans done outside an epilepsy center with that of special protocol MRI scans done at an epilepsy center in delineating relevant lesions of the temporal lobe. SUBJECTS: Eighty-four consecutive patients who had temporal lobe resections for refractory temporal lobe epilepsy between January 1, 1993, and February 1, 1996. DESIGN: The reports of findings on standard MRI scans done outside an epilepsy center were compared with the findings of special protocol MRI scans done with 1.5-mm T1-weighted coronal and 3-mm T2-weighted coronal images (no gaps) on a 1.5-T system. Both sets of MRI findings were compared with findings on histologic examination of the resected tissue. RESULTS: Of the 84 patients, 51 had standard MRI scans done outside an epilepsy center; of these, there were 34 patients with normal results, 10 with tumors, 2 with vascular malformations, 2 with hippocampal atrophy, 2 with unclassified abnormalities, and 1 with cortical malformation. In 32 of the 34 patients with normal results of an MRI scan done outside an epilepsy center, abnormalities were found on our special protocol MRI scans. These included hippocampal atrophy in 27 patients, tumors in 2, and cortical malformations in 1. Additionally, all 17 of the abnormalities detected on the standard MRI scans done outside the epilepsy center were identified on our special protocol MRI scans. Important pathologic abnormalities of the temporal lobe were identified in 16 (35%) of the 46 patients with standard MRI scans done outside an epilepsy center and in 44 (96%) with our special protocol MRI scans. In the 29 patients for whom adequate surgical specimens were available and results of standard MRI scans were normal, our special protocol MRI scans showed the abnormality in 27 (93%). CONCLUSIONS: Conventional neuroimaging studies are inadequate for diagnosing hippocampal sclerosis although they fairly readily detect low-grade tumors and vascular malformations. Magnetic resonance imaging scans for the evaluation of patients with refractory temporal lobe epilepsy should be done with a special temporal lobe protocol and read by physicians experienced with the findings in hippocampal sclerosis. Health care dollars are wasted on neuroimaging done for refractory temporal lobe epilepsy outside epilepsy centers.

Atrophy↗
PubMed2002

Comparison of glaucomatous visual field defects using standard full threshold and Swedish interactive threshold algorithms.

OBJECTIVES: To compare the severity, size, and depth of glaucomatous visual field defects using standard full threshold (FT), Swedish interactive threshold algorithm (SITA) standard (SS), and SITA fast (SF) algorithms of the Humphrey perimeter. METHODS: A prospective observational case series of 77 patients with glaucoma performed FT, SS, and SF 30-2 white-on-white testing programs on the same day on 2 occasions for 1 month. The severity of defects was compared using the mean deviation, pattern standard deviation, Advanced Glaucoma Intervention Study, and Hodapp-Anderson-Parrish severity scores. The sizes of defects were compared using the total number of abnormal points on the pattern deviation plot that fit standard criteria for glaucomatous visual field defects. The depths of the defects were compared using the sum of the threshold values for points identified in the pattern deviation plot as fitting criteria for glaucomatous defects. RESULTS: The mean deviations were slightly better using the SS (-9.6 +/- 7.1 dB) or the SF (-9.1 +/- 6.7 dB) algorithm compared with the FT algorithm (-10.3 +/- 7.1 dB) (P<.005). There were no significant differences in pattern standard deviations between SS (8.6 +/- 4.0, P =.08) and SF (8.1 +/- 3.6, P =.19) compared with FT (8.3 +/- 3.3), although the pattern standard deviation was higher in SS fields compared with SF fields (P<.001). Advanced Glaucoma Intervention Study scores were slightly better when the SS (7.5 +/- 5.6) or SF (7.2 +/- 5.4) algorithm was used compared with the FT algorithm (8.6 +/- 5.4) (P<.001). The sizes of glaucomatous defects were slightly larger using the SS (20.9 +/- 10.7) algorithm compared with the FT algorithm (19.2 +/- 10.9) (P =.004) but not the SF algorithm (20.0 +/- 10.6) (P =.11). The depth of defects measured by the SS (220.4 +/- 108.0 dB) and SF (219.8 +/- 101.3 dB) algorithms was significantly shallower compared with that measured by the FT algorithm (152.3 +/- 79.1 dB) (P<.001). There were no significant differences in Hodapp-Anderson-Parrish severity scores among algorithms (P =.12). CONCLUSIONS: Glaucomatous defects are measured significantly shallower using the new SITA algorithms but are approximately the same size and severity compared with FT measurements. Care should be taken when using threshold values to compare glaucomatous defects in a patient when converting from FT to SITA algorithms.

Adult↗
PubMed2002

Standardized trauma resuscitation: female hearts respond better.

HYPOTHESIS: Women respond better to standardized shock resuscitation compared with similarly severely injured men. DESIGN: Severely injured patients who met specific criteria were resuscitated using a standardized protocol with no adjustment for gender. The resuscitation protocol was used to attain and to maintain an oxygen delivery index of 600 mL/min. m(2) or greater (DO(2)I > or = 600) for the first 24 hours in the intensive care unit (ICU). Interventions, responses, and outcomes for the 2 cohorts were compared. Data were analyzed using analysis of variance, chi(2), and t tests; P<.05 was considered significant. SETTING: A 20-bed regional level I trauma center ICU. PATIENTS: Patients at high risk of postinjury multiple organ failure (major organ or vascular injury and/or skeletal fractures, initial arterial base deficit of 6 mEq/L or greater, requirement for 6 units or more of packed red blood cells in the first 12 hours after hospital admission, or age > or = 65 years with any 2 previous criteria). INTERVENTIONS: Pulmonary artery catheter, packed red blood cell transfusion, crystalloid fluid infusion, inotrope, and vasopressor support, as needed, in that sequence, to maintain DO(2)I > or = 600. MAIN OUTCOME MEASURES: Hemodynamic response to resuscitation, fluid, and packed red blood cell volume. RESULTS: During 2000, 58 patients (38 men, 20 women) met criteria and were resuscitated using our standardized protocol. Demographics and outcomes were similar for both cohorts. Requirements for and responses to standardized resuscitation were also similar, except for volume loading. The female cohort required less lactated Ringer solution volume (12 +/- 1 vs 8 +/- 2 L, P<.05), required less Starling curve intervention (42% vs 15%, P<.05), and maintained the DO(2)I goal with average pulmonary capillary wedge pressure that was less than that of the male cohort. CONCLUSION: Review of prospective data from standardized shock resuscitation for female and male cohorts demonstrates that women respond better to standardized resuscitation compared with similarly severely injured men.

Adult↗
PubMed2000

Improving residents' compliance with standards of ambulatory care: results from the VA Cooperative Study on Computerized Reminders.

CONTEXT: Computerized systems to remind physicians to provide appropriate care have not been widely evaluated in large numbers of patients in multiple clinical settings. OBJECTIVE: To examine whether a computerized reminder system operating in multiple Veterans Affairs (VA) ambulatory care clinics improves resident physician compliance with standards of ambulatory care. DESIGN, SETTING, AND PARTICIPANTS: A total of 275 resident physicians at 12 VA medical centers were randomly assigned in firms or half-day clinic blocks to either a reminder group (n = 132) or a control group (n = 143). During a 17-month study period (January 31, 1995-June 30, 1996), the residents cared for 12,989 unique patients for whom at least 1 of the studied standards of care (SOC) was applicable. MAIN OUTCOME MEASURES: Compliance with 13 SOC, tracked using hospital databases and encounter forms completed by residents, compared between residents in the reminder group vs those in the control group. RESULTS: Measuring compliance as the proportion of patients in compliance with all applicable SOC by their last visit during the study period, the reminder group had statistically significantly higher rates of compliance than the control group for all standards combined (58.8% vs 53.5%; odds ratio [OR], 1.24; 95% confidence interval [CI], 1.08-1.42; P =.002) and for 5 of the 13 standards examined individually. Measuring compliance as the proportion of all visits for which care was indicated in which residents provided proper care, the reminder group also had statistically significantly higher rates of compliance than the control group for all standards combined (17.9% vs 12.2%; OR, 1.57; 95% CI, 1.45-1.71; P<.001) and for 9 of the 13 standards examined individually. The benefit of reminders, however, declined throughout the course of the study, even though the reminders remained active. CONCLUSIONS: Our data indicate that reminder systems installed at multiple sites can improve residents' compliance to multiple SOC. The benefits of such systems, however, appear to deteriorate over time. Future research needs to explore methods to better sustain the benefits of reminders. JAMA. 2000;284:1411-1416.

Adult↗
PubMed2004

Clinical trials in sub-Saharan Africa and established standards of care: a systematic review of HIV, tuberculosis, and malaria trials.

CONTEXT: The minimum standard of care required for participants in clinical trials conducted in resource-poor settings is a matter of controversy; international documents offer contradictory guidance. OBJECTIVE: To determine whether recently published trials conducted in sub-Saharan Africa met standards of care consistent with best current clinical standards for human immunodeficiency virus (HIV) treatment, tuberculosis treatment, and malaria prevention. DATA SOURCES: Trials published during or after January 1998 that were indexed at the time of the MEDLINE and Cochrane Controlled Trials Register Search (November 20, 2003). STUDY SELECTION: All randomized clinical trials that were conducted in sub-Saharan Africa in 3 clinical domains: HIV disease, tuberculosis treatment, and malaria prophylaxis. DATA EXTRACTION: To establish criteria for best current standards of care, evidence from the literature and published guidelines accepted for well-resourced settings were analyzed; the actual care offered in the trial was then compared with these standards. DATA SYNTHESIS: A total of 128 eligible articles described data from 73 different randomized clinical trials. Only 12 trials (16%) provided care that met guidelines to both intervention and control patients. Only 1 of the 34 trials that enrolled patients with HIV disease provided antiretroviral treatment that conformed to guidelines. Conversely, all tuberculosis treatment trials (n = 13, including 3 for HIV-infected patients) provided tuberculosis therapy that conformed to guidelines. Twenty-one (72%) of 29 malaria prophylaxis trials tested interventions that met guidelines, but only 3 (10%) used any active prophylactic intervention in the control group. Of the 59 trials (81%) that reported on the process of ethical review, all were reviewed by a host African institution and 64% were additionally reviewed by an institution in a developed country. CONCLUSIONS: Rates of adherence to established clinical guidelines of care in randomized clinical trials of HIV treatment, tuberculosis treatment, and malaria prophylaxis varied considerably between disease categories. In determining clinical standards for trials in sub-Saharan Africa, researchers and ethics committees appear to take the local level of care into account.

Africa South of the Sahara↗
PubMed2004

Pegylated interferon alfa-2b vs standard interferon alfa-2b, plus ribavirin, for chronic hepatitis C in HIV-infected patients: a randomized controlled trial.

CONTEXT: Treatment of chronic hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected patients is a growing concern. Most data on the virologic efficacy and safety of the combination of peginterferon alfa-2b and ribavirin in coinfected patients come from uncontrolled studies. OBJECTIVE: To study the safety and efficacy of peginterferon alfa-2b plus ribavirin vs standard interferon alfa-2b plus ribavirin in HIV-HCV coinfected patients. DESIGN AND SETTINGS: A multicenter, randomized, parallel-group, open-label trial. Patients were enrolled from February 2000 to February 2002 and followed up for 72 weeks. PATIENTS: Four hundred twelve HIV-HCV coinfected patients with detectable serum HCV-RNA, abnormal liver histology, a CD4 cell count of at least 200 x 10(6)/L, and stable plasma HIV-RNA. INTERVENTION: Treatment with ribavirin 400 mg twice a day, orally, plus either peginterferon alfa-2b (1.5 microg/kg subcutaneous injection once a week) or standard interferon alfa-2b (3 million units of subcutaneous injection 3 times a week) for 48 weeks. MAIN OUTCOME MEASURES: Sustained virologic response, defined by undetectable serum HCV-RNA at week 72. RESULTS: More patients had sustained virologic responses in the peginterferon group than in the standard interferon group (27% vs 20%, P = .047). This difference between the treatments was found in patients with HCV genotype 1 or 4 infection (17% for peginterferon vs 6% for standard interferon, P = .006) but was not found in patients with HCV genotype 2, 3, or 5 (44% for peginterferon vs 43% for standard interferon, P = .88). Together, a decline in HCV-RNA of less than 2 log10 from baseline and detectable serum HCV-RNA at week 12 predicted 99% of treatment failures. Histologic activity diminished and fibrosis stabilized in virologic responders. The 2 regimens showed similar tolerability although dose modifications for clinical and biological events were more frequent with peginterferon. Eleven cases of pancreatitis or symptomatic hyperlactatemia were observed, all in patients receiving didanosine-containing antiretroviral regimens. CONCLUSION: In combination with ribavirin, treatment with peginterferon alfa-2b is more effective than standard interferon alfa-2b for HCV infection in HIV-infected patients.

Adult↗
PubMed2005

Evaluation of new treatments in radiation oncology: are they better than standard treatments?

CONTEXT: The superiority of innovative over standard treatments is not known. To describe accurately the outcomes of innovations that are tested in randomized controlled trials (RCTs) 3 factors have to be considered: publication rate, quality of trials, and the choice of the adequate comparator intervention. OBJECTIVE: To determine the success rate of innovative treatments by assessing preferences between experimental and standard treatments according to original investigators' conclusions, determining the proportion of RCTs that achieved primary outcomes' statistical significance, and performing meta-analysis to examine if the summary point estimate favored innovative vs standard treatments. DATA SOURCES: Randomized controlled trials conducted by the Radiation Therapy Oncology Group (RTOG). STUDY SELECTION: All completed phase 3 trials conducted by the RTOG since its creation in 1968 until 2002. For multiple publications of the same study, we used the one with the most complete primary outcomes and with the longest follow-up information. DATA EXTRACTION: We used the US National Cancer Institute definition of completed studies to determine the publication rate. We extracted data related to publication status, methodological quality, and treatment comparisons. One investigator extracted the data from all studies and 2 independent investigators extracted randomly about 50% of the data. Disagreements were resolved by consensus during a meeting. DATA SYNTHESIS: Data on 12,734 patients from 57 trials were evaluated. The publication rate was 95%. The quality of trials was high. We found no evidence of inappropriateness of the choice of comparator. Although the investigators judged that standard treatments were preferred in 71% of the comparisons, when data were meta-analyzed innovations were as likely as standard treatments to be successful (odds ratio for survival, 1.01; 99% confidence interval, 0.96-1.07; P = .5). In contrast, treatment-related mortality was worse with innovations (odds ratio, 1.76; 99% confidence interval, 1.01-3.07; P = .008). We found no predictable pattern of treatment successes in oncology: sometimes innovative treatments are better than the standard ones and vice versa; in most cases there were no substantive differences between experimental and conventional treatments. CONCLUSION: The finding that the results in individual trials cannot be predicted in advance indicates that the system and rationale for RCTs is well preserved and that successful interventions can only be identified after an RCT is completed.

Clinical Trials, Phase III as Topic↗
PubMed1997

Proposed new data file standard for flow cytometry, version FCS 3.0.

In 1984, the first flow cytometry data file format was proposed as Flow Cytometry Standard 1.0 (FCS1.0). FCS 1.0 provided a uniform file format allowing data acquired on one computer to be correctly read and interpreted on other computers running a variety of operating systems. That standard was modified in 1990 and adopted by the Society of Analytical Cytology as FCS 2.0. Here, we report on an update of the FCS 2.0 standard which we propose to designate FCS 3.0. We have retained the basic four segment structure of earlier versions (HEADER, TEXT, DATA and ANALYSIS) in order to maintain analysis software compatibility, where possible. The changes described in this proposal include a method to collect files larger than 100 megabytes (not possible in earlier versions of the standard), the inclusion of international characters in the TEXT portions of the file, a method of verifying data integrity using a 16-bit cyclic redundancy check, and increased keyword support for cluster analysis and time acquisition. This report summarizes the work of the ISAC Data File Standards Committee. The complete and detailed FCS 3.0 standard is available through the ISAC office [Sherwood Group, 60 Revere Drive, Ste 500, Northbrook, IL 60062, phone: (847) 480-9080 ext. 231, fax: (847) 480-9282, E-mail: isac@sherwood-group.com] or through the internet at the ISAC WWW site, http://nucleus.immunol.washington.edu/ISAC.ht ml.

Database Management Systems↗
PubMed1999

On standardizing the MR image intensity scale.

The lack of a standard image intensity scale in MRI causes many difficulties in image display and analysis. A two-step postprocessing method is proposed for standardizing the intensity scale in such a way that for the same MR protocol and body region, similar intensities will have similar tissue meaning. In the first step, the parameters of the standardizing transformation are "learned" from a set of images. In the second step, for each MR study these parameters are used to map their histogram into the standardized histogram. The method was tested quantitatively on 90 whole-brain studies of multiple sclerosis patients for several protocols and qualitatively for several other protocols and body regions. Measurements using mean squared difference showed that the standardized image intensities have statistically significantly (P < 0.01) more consistent range and meaning than the originals. Fixed gray level windows can be established for the standardized images and used for display without the need of per case adjustment. Preliminary results also indicate that the method facilitates improving the degree of automation of image segmentation. Magn Reson Med 42:1072-1081, 1999.

Algorithms↗
PubMed2000

Numerical tissue characterization in MS via standardization of the MR image intensity scale.

Image intensity standardization is a recently developed postprocessing method that is capable of correcting the signal intensity variations in MR images. We evaluated signal intensity of healthy and diseased tissues in 10 multiple sclerosis (MS) patients based on standardized dual fast spin-echo MR images using a numerical postprocessing technique. The main idea of this technique is to deform the volume image histogram of each study to match a standard histogram and to utilize the resulting transformation to map the image intensities into standard scale. Upon standardization, the coefficients of variation of signal intensities for each segmented tissue (gray matter, white matter, lesion plaques, and diffuse abnormal white matter) in all patients were significantly smaller (2.3-9.2 times) than in the original images, and the same tissues from different patients looked alike, with similar intensity characteristics. Numerical tissue characterizability of different tissues in MS achieved by standardization offers a fixed tissue-specific meaning for the numerical values and can significantly facilitate image segmentation and analysis.

Adult↗
PubMed2004

The British approach to asbestos standard setting: 1898-2000.

BACKGROUND: The asbestos industry started in the late 1870s, and the first accounts of severe respiratory disease in its workers were published in England (1898, 1906), France (1907), and Italy (1908). For a hundred years, a series of increasingly lower standards were set for asbestos in Britain: initially they purported to prevent asbestosis, and latterly to reduce asbestosis and malignancies to acceptable levels. METHODS: Published accounts of how British asbestos exposure standards came to be derived are reviewed in the light of archival materials originated by industry and government. RESULTS: The earliest standard, of necessity, was not evidence based and while subsequent standards purported to relate doses to effects, the indifferent quality of the measurement of dose, and the poor discrimination of effects, militated against arriving at a standard in which trust should be placed. Each successive standard that was accepted, conformed to what could be achieved in production processes, as far as it was reasonably practicable on technological and economic grounds. CONCLUSIONS: For the better part of a hundred years, confidence was misplaced in the ability of process engineers and physicians to protect workers against asbestos. Finally, deciding that asbestos was neither technologically nor economically essential, and was unsafe in use, Europe issued a Directive, to which Britain will conform, that will virtually ban it use throughout the Community by 2006.

Asbestos↗
PubMed2004

Reliability of the knee examination in osteoarthritis: effect of standardization.

OBJECTIVE: To assess the reliability of physical examination of the osteoarthritic (OA) knee by rheumatologists, and to evaluate the benefits of standardization. METHODS: Forty-two physical signs and techniques were evaluated using a 6 x 6 Latin square design. Patients with mild to severe knee OA, based on physical and radiographic signs, were examined in random order prior to and following standardization of techniques. For those signs with dichotomous scales, agreement among the rheumatologists was calculated as the prevalence-adjusted bias-adjusted kappa (PABAK), while for the signs with continuous and ordinal scales, a reliability coefficient (R(c)) was calculated using analysis of variance. A PABAK of >0.60 and an R(c) of >0.80 were considered to indicate adequate reliability. RESULTS: Adequate poststandardization reliability was achieved for 30 of 42 physical signs/techniques (71%). The most highly reliable signs identified by physical examination of the OA knee included alignment by goniometer (R(c) = 0.99), bony swelling (R(c) = 0.97), general passive crepitus (R(c) = 0.96), gait by inspection (PABAK = 0.78), effusion bulge sign (R(c) = 0.97), quadriceps atrophy (R(c) = 0.97), medial tibiofemoral tenderness (R(c) = 0.94), lateral tibiofemoral tenderness (R(c) = 0.85), patellofemoral tenderness by grind test (R(c) = 0.94), and flexion contracture (R(c) = 0.95). The standardization process resulted in substantial improvements in reliability for evaluation of a number of physical signs, although for some signs, minimal or no effect of standardization was noted. After standardization, warmth (PABAK = 0.14), medial instability at 30 degrees flexion (PABAK = 0.02), and lateral instability at 30 degrees flexion (PABAK = 0.34) were the only 3 signs that were highly unreliable. CONCLUSION: With the exception of physical examinations for instability, a comprehensive knee examination can be performed with adequate reliability. Standardization further improves the reliability for some physical signs and techniques. The application of these findings to future OA studies will contribute to improved outcome assessments in OA.

Adult↗
PubMed1991

The S wave in acute anterior Q-wave myocardial infarction: a study with serial multilead precordial maps and standard ECGs.

To investigate the relationship of S waves with R waves and/or Q waves in the ECGs of patients with acute myocardial infarction, 20 patients with anterior Q-wave infarcts had serial 49-lead precordial maps and simultaneously recorded standard ECGs on admission and at 13 predetermined time intervals, extending to their discharge from the hospital. The sums of S waves (sigma S) from ECG leads of both precordial maps and standard ECGs showing ST-segment elevation on admission were correlated with the corresponding sums of R waves (sigma R) and/or Q waves (sigma Q). Correlation of sigma S by the precordial maps and the sigma S by the standard ECG was good (r = 0.88). However, correlation of sigma S with sigma R and sigma Q by both the precordial maps and standard ECG were poor (r values ranged between -0.02 and -0.32). Fair correlations were found between sigma S + sigma Q and the corresponding sigma R by both ECG systems (r = 0.36, precordial map and r = 0.40, standard ECG). The present study demonstrates (1) that precordial (consequently partial) ECG mapping systems have no advantage over standard precordial ECG, and (2) that quantitative data from S waves correlate weakly with similar information from corresponding R waves or Q waves, but fairly with the latter two combined, as recorded by the two ECG systems employed.

Data Collection↗
PubMed2002

Financial analysis of patients with newly diagnosed acute myelogenous leukemia on protocol or standard therapy.

BACKGROUND: Medicare and third-party payers may be reluctant to pay for investigational (protocol) therapy for patients with cancer on the premise that such treatment is more expensive than standard therapy. However, prior studies that have attempted to compare protocol therapy with standard therapy have been difficult to interpret because of the assortment of malignancies studied and the lack of suitable control groups of patients who received standard therapy. METHODS: In the current study, the authors conducted a retrospective review of the financial charges associated with protocol or nonprotocol (standard) chemotherapy in patients with a single malignancy, newly diagnosed acute myelogenous leukemia (AML), who received their initial course of chemotherapy ("induction") at the Memorial Sloan-Kettering Cancer Center (MSKCC) between 1996 and 1999. Protocol and nonprotocol groups were analyzed according to clinical characteristics and standard prognostic features to determine whether the two groups were comparable. Median charges for all patients were determined using a database that linked clinical information, financial data, and clinical outcomes. RESULTS: A total of 353 patients with newly diagnosed AML were registered at MSKCC during the time period studied; of these, 79 patients (22%) received all of their care at the institution. Thirty patients (38%) received treatment on an investigational protocol. Forty-nine patients (62%) did not receive protocol therapy for the following reasons: 10 patients (20%) did not meet eligibility criteria, 4 patients (8%) were eligible for protocol therapy but declined, and 35 patients (71%) met protocol criteria but were not offered protocol therapy based on the judgment of their primary oncologist. The groups were not comparable because patients treated with standard therapy were older and had a poorer initial Eastern Cooperative Oncology Group (ECOG) performance status. Overall median charges for patients in the nonprotocol group were higher than for patients treated on a protocol although charges were not related to age, initial ECOG performance status, or cytogenetic risk group. CONCLUSIONS: Although charges for the nonprotocol group were higher, specific factors responsible for this difference were not identified. This study emphasizes the problems inherent in assembling suitable groups of patients for comparison.

Adult↗