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Subjective Criteria (subjective + criterion)
Selected AbstractsIdentification of Optimal Electrocardiographic Criteria for the Diagnosis of Unrecognized Myocardial Infarction: A Population-Based StudyANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2005Khawaja Afzal Ammar M.D. Background: Despite using the same tool (ECG), the proportion of myocardial infarctions that goes unrecognized varies from 20% to 60% in population-based studies. The reasons for such wide variations have not been studied. We sought to evaluate the effect of ECG-MI criteria and study methodology on the prevalence of unrecognized myocardial infarction (UMI) and to identify the optimal ECG-MI criteria for UMI detection in epidemiologic studies. Methods: A random population-based sample of 2042 adults, age ,45 years, underwent history, medical record abstraction and ECG. Six different ECG-MI criteria and two subjective recognized myocardial infarction (RMI) identification criteria, from different published studies, were applied to the same survey ECG. The operating test characteristics of different criteria were compared with the objective criterion standard of a RMI by Gillum criteria. Results: The UMI proportion estimates varied from 32% to 61% due to variation in ECG-MI criteria, while keeping the study population, MI recognition criteria, and ECG constant. Subjective criteria for MI recognition had limited value (positive predictive value of 44,93%) in picking up RMI. Depending on the ECG abnormality used to define MI, ECG reading had widely varying sensitivity (21,37%; P < 0.0001) with consistently high specificity (92,97%) for detection of RMI. Conclusions: The prevalence estimates of UMI vary widely and are strongly dependent on the ECG-MI and MI recognition criteria. Future studies of UMI should explicitly recognize this variation and select the ECG-MI criteria that match their study aims. [source] Role of meta-analysis of clinical trials for Alzheimer's diseaseDRUG DEVELOPMENT RESEARCH, Issue 3 2002Jesús M. López Arrieta Abstract Alzheimer's disease (AD) is a growing worldwide medical, social, and economic problem. In all countries, both prevalence and incidence of this disorder increase with age. The task of translating scientific clinical research into effective interventions for dementia has proved to be a difficult challenge. Data about the effects of therapeutic interventions come from several sources of evidence, ranging from studies with little potential for systematic bias and minimal random error, such as well-designed randomized controlled trials, through controlled but nonrandomized cohort and case-control studies, all the way to opinions based on laboratory evidence or theory. Although clinical trials are widespread in AD, there is increasing recognition that the results of studies do not necessarily apply to the type of patients that are seen by clinicians because of differences in patient characteristics, comorbidities, cotherapies, severity of disease, compliance, local circumstances, and patients preferences, which may differ sufficiently from those in the trial situation to attenuate or change the benefit-to-risk ratio. There are several methods to address those issues, like pragmatic trials and n-of-1 trials. When data from randomized clinical trials do not provide clear answers from sufficiently similar studies in the magnitude of effect sizes, lack of statistical significance, or identification of subgroups, systematic reviews and meta-analysis may help to provide a better summary of the data. A major difference between a traditional review and a systematic is the systematic nature in which studies are chosen and appraised. Traditional reviews are written by experts in the field who use differing and often subjective criteria to decide what studies to include and what weight to give them, and hence the conclusions are often very diverse, depending on the reviewer. Publication and selection bias is a major concern of traditional reviews. Systematic reviews and meta-analysis are being increasingly used in dementia, propelled by the Cochrane Dementia and Cognitive Improvement Group, to make decisions about treatment, management, and care and to guide future research. This narrative review describes the rationale for randomized clinical trials and systematic reviews in dementia, particularly AD. Drug Dev. Res. 56:401,411, 2002. © 2002 Wiley-Liss, Inc. [source] Model uncertainty in the ecosystem approach to fisheriesFISH AND FISHERIES, Issue 4 2007Simeon L. Hill Abstract Fisheries scientists habitually consider uncertainty in parameter values, but often neglect uncertainty about model structure, an issue of increasing importance as ecosystem models are devised to support the move to an ecosystem approach to fisheries (EAF). This paper sets out pragmatic approaches with which to account for uncertainties in model structure and we review current ways of dealing with this issue in fisheries and other disciplines. All involve considering a set of alternative models representing different structural assumptions, but differ in how those models are used. The models can be asked to identify bounds on possible outcomes, find management actions that will perform adequately irrespective of the true model, find management actions that best achieve one or more objectives given weights assigned to each model, or formalize hypotheses for evaluation through experimentation. Data availability is likely to limit the use of approaches that involve weighting alternative models in an ecosystem setting, and the cost of experimentation is likely to limit its use. Practical implementation of an EAF should therefore be based on management approaches that acknowledge the uncertainty inherent in model predictions and are robust to it. Model results must be presented in ways that represent the risks and trade-offs associated with alternative actions and the degree of uncertainty in predictions. This presentation should not disguise the fact that, in many cases, estimates of model uncertainty may be based on subjective criteria. The problem of model uncertainty is far from unique to fisheries, and a dialogue among fisheries modellers and modellers from other scientific communities will therefore be helpful. [source] Distinguishing between naturally and culturally flaked cobbles: A test case from Alberta, CanadaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 7 2004Jason David Gillespie Distinguishing between naturally and culturally produced, simply flaked cobbles has been a problem for proponents of a pre-Clovis occupation in the Americas. Several sites in Alberta have been assigned a pre-Clovis status based on the presence of simply flaked cobbles found in Late Pleistocene till deposits. Historically, these types of assemblages have been assigned a cultural status based on subjective criteria and appeals to the analyst's expertise. To determine the archaeological status of two such assemblages from Alberta (Varsity Estates and Silver Springs), they were compared to a known natural assemblage and two known cultural assemblages. Chi-square testing was used to evaluate several lithic attributes. Only those attributes that statistically differentiated between natural and cultural assemblages were used for further analyses. All cobbles were then scored using these attributes. A point was awarded when a statistically significant attribute of human-manufacture was present. These points were then totaled, providing an aggregate score for each cobble. These scores were plotted to determine whether the test assemblages had closer affinities with the known natural or known cultural assemblages. The results indicate that the proposed pre-Clovis assemblages have closer affinities to known natural assemblages than to cultural assemblages. Our results suggest that these sites provide no evidence for a pre-Clovis occupation in the Americas. © 2004 Wiley Periodicals, Inc. [source] Are single fractions of radiotherapy suitable for plantar fasciitis?JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2004Fabian Schwarz Summary The use of radiotherapy for plantar fasciitis has never been reported in Australasia and is scarcely found in the English language medical literature, but it is commonly used in Europe, especially in Germany. In Europe, treatment courses consisting of multiple small fractions have been associated with high levels of pain relief. In the present report, the use of single fractions or radiotherapy was evaluated by reviewing seven consecutive patients referred for treatment and by applying objective and subjective criteria for pain relief. One patient died of unrelated causes soon after treatment and one declined to receive radiotherapy. Four patients each received a single dose of 8 Gy resulting in complete pain relief. One patient was treated with 8 Gy and 12 weeks later was retreated achieving partial pain relief. A follow-up interview was conducted after a mean of 15.6 months, ranging from 1.5 to 30 months. No acute or late effects occurred; however, the possibility that delayed effects may yet occur, particularly carcinogenesis, cannot be excluded. Radiotherapy for this common condition should be investigated further as it might be safer and more effective than other methods currently in use. [source] Conceptualizing and evaluating career successJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 2 2005Peter A. Heslin Within the vast literature on the antecedents of career success, the success criterion has generally been operationalized in a rather deficient manner. Several avenues for improving the conceptualization and measurement of both objective and subjective career success are identified. Paramount among these is the need for greater sensitivity to the criteria that study participants, in different contexts, use to construe and judge their career success. This paper illustrates that contextual and individual factors are likely to be associated with the relative salience of objective and subjective criteria of career success. Drawing on social comparison theory, propositions are also offered about when self- and other-referent success criteria are likely to be most salient. A broader research agenda addresses career success referent choice, organizational interventions, and potential cultural differences. This article maps out how future research can be more sensitive to how people actually do conceptualize and evaluate their own career success. Copyright © 2005 John Wiley & Sons, Ltd. [source] (613) Radiculopathy Treatment Assessment Using Pain Tolerance TestPAIN MEDICINE, Issue 2 2000Article first published online: 25 DEC 200 Authors: Y. Eugene Mironer, Carolinas Center for Advanced Management of Pain; Judson J. Somerville, The Pain Management Clinic of Laredo Current measurements of the outcomes of chronic radiculopathy treatment are limited to subjective criteria: level of pain, range of motion, etc. Our previous study showed that nerve conductivity does not correlate well with the intensity of pain after treatment of radiculopathy (1). In the current study we looked at the Pain Tolerance Threshold (PTT) as a possible measurement of the results of radiculopathy treatment. Twenty patients with chronic radiculopathy (13 lumbar and 7 cervical) underwent epidural steroid injections at the level of involvement. Before, and approximately one week after the procedure, we measured PTT in both the involved and contralateral extremity at 3 different frequencies (5Hz, 250Hz, and 2000 Hz) using Neurometer. Level of pain was also assessed using a Visual Analog Scale (VAS). Initial PTT results showed great interpersonal variability. Nearly half of the patients did not show significant differences in PTT between affected and unaffected sides. Of interest, the majority experienced intolerable pain at 2000 Hz stimulation at lower than maximal intensity output, which contradicts previous findings (2). Dynamics of the PTT measurements after treatment did not directly correlate with changes in the level of pain. Nevertheless, in 7 out of 8 patients with low PTT (relative to the unaffected side) it increased significantly, with noticeable decrease of VAS score. Similar results were not found in patients with either normal initial PTT score or minimal improvement of pain. 1. Mironer YE, Somerville JJ The current perception threshold evaluation in radiculopathy: efficacy in diagnosis and assessment of treatment results. Pain Digest 1998;8:37,38. 2. Liu SS, Gerancher JC, Bainton BG, et al. The effects of electrical stimulation at different frequencies on perception and pain in human volunteers: epidural versus intravenous administration of fentanyl. Anesth Analg 1996;82:98,102. [source] Results from the International Cataract Surgery Outcomes StudyACTA OPHTHALMOLOGICA, Issue thesis2 2007Jens Christian Norregaard MD Abstract It is widely accepted that cataract extraction with intraocular lens implantation is a highly effective and successful procedure. However, quality assessments and studies of effectiveness should still be undertaken. As with any surgical treatment modality, complications may occur, leading to suboptimal outcomes, additional health costs and deterioration in patients' functional capacity. International variation in clinical practice patterns and outcomes can serve as important pointers in the attempt to identify areas amenable to improvements in quality and cost-effectiveness. Once demonstrated, similar clinical results obtained in different health care systems can improve the level of confidence in a clinical standard against which the quality of care can be evaluated. The International Cataract Surgery Outcomes Study was established in 1992. The objective of this international comparative research project was to compare cataract management, outcomes of surgery and quality of care in four international sites. The study was conducted in the 1990s, since when many developments and refinements have emerged within cataract surgery. The actual figures reported in this thesis may no longer be of specific relevance as a decade has passed since their collection. However, the research questions and methods used in the study are still highly important and justify the publication of this report. The report deals with problems related to quality assessment, benchmarking, and the establishment and design of nationwide clinical databases , issues that are currently the focus of much attention. Moreover, the problems related to cross-national comparisons are increasingly relevant as more international databases are established. The study makes suggestions on how to report and compare objective as well as subjective criteria for surgery. The issue of how to report subjective criteria is a particular subject of current discussion. Four sites with high-quality health care systems were examined in this study: the USA, Denmark, the Province of Manitoba (Canada), and Barcelona (Spain). The design of the international research programme was based on methods developed by the US National Cataract Surgery Outcomes Study conducted by the US Cataract Patients Outcomes Research Team. The International Cataract Surgery Outcomes Study comprised three separate studies: a survey of ophthalmologists; a prospective cohort study, and a retrospective register-based cohort study. The survey study was based on data generated by a self-administered questionnaire completed by ophthalmologists in the four study areas. The questionnaire examined routine clinical practice involving patients considered for cataract surgery, and included questions on anaesthesia, monitoring and surgical techniques. The prospective cohort study was a large-scale, longitudinal observational study of patients undergoing first-eye cataract surgery in each study site. Patients were sampled consecutively from multiple clinics and followed for 4 months postoperatively. The retrospective cohort study was based on the Danish National Patient Register and claims data from the USA. This study could not be carried out in Barcelona or Manitoba as no suitable administrative databases were available. The papers based on register databases deal with retinal detachment and endophthalmitis but are not included in this thesis as the material was previously reported in my PhD thesis. The application of the studies was highly co-ordinated among the four sites and similar methods and instruments were used for data collection. The development of the data collection strategy, questionnaires, clinical data forms and data analyses were co-ordinated through weekly telephone conferences, annual in-person conferences, correspondence by mail or fax, and the exchange of sas programs and data files via the Internet. The survey study was based on responses from 1121 ophthalmologists in the four sites and results were presented in two papers. Within the previous year the participating ophthalmologists had performed a total of 212 428 cataract surgeries. With regard to preoperative ophthalmic testing, the present study reveals that refraction, fundus examination and A-scanning were performed routinely by most surgeons in all four sites. Other tests were reported to be performed routinely by some surgeons. It is unclear why any surgeon would use these other tests routinely in cataract patients with no ocular comorbidity. It appears that if this recommendation from the US Clinical Practice Guidelines Panel was broadly accepted, the use of these procedures and costs of care could be reduced, especially in Barcelona, the USA and Canada. Restricted use of medical screening tests was reported in Denmark. If this restricted screening were to be implemented in the USA, Canada and Barcelona, it would have significant resource implications. The most striking finding concerned the difference in monitoring practice between Denmark and each of the other three sites. In Denmark, monitoring equipment is seldom used and only occasionally is an anaesthesiologist present during cataract surgery. By contrast, in the other study sites, the presence of an anaesthesiologist using monitoring equipment is the norm. Adopting the Danish model in other sites would potentially yield significant cost savings. The results represent part of the background data used to inform the decision to conduct the two large-scale, multicentre Studies of Medical Testing for Cataract Surgery. The current study is an example of how surveys of clinical practice can pinpoint topics that need to be examined in randomized clinical trials. For the second study, 1422 patients were followed from prior to surgery until 4 months postoperatively. Preoperatively, a medical history was obtained and an ophthalmic examination of each patient performed. After consent had been obtained, patients were contacted for an in-depth telephone interview. The interview was repeated 4 months postoperatively. The interview included the VF-14, an index of functional impairment in patients with cataract. Perioperative data were available for 1344 patients (95%). The 4-month postoperative interview and clinical examination were completed by 1284 patients (91%). Main reasons for not re-evaluating patients were: surgery was cancelled (3%); refusal to participate (2%); lost to follow-up (1%), and death or being too sick (1%). The results have been presented in several papers, of which four are included in this thesis. One paper compared the preoperative clinical status of patients across the four sites and showed differences in both visual acuity (VA) and VF-14 measures. The VF-14 is a questionnaire scoring disability related to vision. The findings suggest that indications for surgery in comparable patients were similar in the USA and Denmark and were more liberal than in Manitoba and Barcelona. The results highlight the need to control for patient case mix when making comparisons among providers in a clinical database. This information is important when planning national databases that aim to compare quality of care. A feasible method may be to use one of the recently developed systems for case severity grading before cataract surgery. In another paper, perioperative clinical practice and rates of early complications following cataract surgery were compared across the four health care systems. Once again, the importance of controlling for case mix was demonstrated. Significant differences in clinical practice patterns were revealed, suggesting a general trend towards slower diffusion of new medical technology in Europe compared with North America. There were significant differences across sites in rates of intra- and early postoperative events. The most important differences were seen for rates of capsular rupture, hyphaema, corneal oedema and elevated pressure. Rates of these adverse events might potentially be minimized if factors responsible for the observed differences could be identified. Our results point towards the need for further research in this area. In a third paper, 4-month VA outcomes were compared across the four sites. When mean postoperative VA or crude proportions of patients with a visual outcome of <,0.67 were compared across sites, a much poorer outcome was seen in Barcelona. However, higher age, poorer general health status, lower preoperative VA and presence of ocular comorbidity were found to be significant risk factors associated with increased likelihood of poorer postoperative VA. The proportions of patients with these risk factors varied across sites. After controlling for the different distributions of these factors, no significant difference remained across the four sites regarding risk of a poor visual outcome. Once again the importance of controlling for case mix was demonstrated. In the fourth paper, we examined the postoperative VF-14 score as a measure of visual outcomes for cataract surgery in health care settings in four countries. Controlling for case mix was also necessary for this variable. After controlling for patient case mix, the odds for achieving an optimal visual function outcome were similar across the four sites. Age, gender and coexisting ocular pathology were important predictors of visual functional outcome. Despite what seemed to be an optimal surgical outcome, a third of patients still experienced visual disabilities in everyday life. A measure of the VF-14 might help to elucidate this issue, especially in any study evaluating the benefits of cataract surgery in a public health care context. [source] | |||||||||||||