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Understanding the minimum clinically important difference: a review of concepts and methods. 总被引:2,自引:0,他引:2
Anne G Copay Brian R Subach Steven D Glassman David W Polly Thomas C Schuler 《The spine journal》2007,7(5):541-546
BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated. 相似文献
84.
Trauma und Berufskrankheit - Nur 0,4–1% aller Frakturen betreffen die Skapula, die meisten davon können erfolgreich konservativ funktionell behandelt werden. Zur Identifikation der... 相似文献
85.
S. Champain Th. David Ch. Mazel A. Mitulescu W. Skalli 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(4):337-347
Adult low-grade isthmic spondylolisthesis is often treated by posterolateral lumbar fusion (PLF), with a certain rate of complications and non-return to work. Alternatives to fusion, like pars defect repair (PDR), were used with encouraging results in young populations and athletes but their outcomes were rarely evaluated for adult patients. This retrospective study quantitatively analysed the long-term outcomes in adult isthmic spondylolisthesis patients treated by PLF or PDR. At a mean follow-up of 9 years, clinical, socio-professional, radiological data and Stauffer-Coventry score were available for 59 patients (39 cases treated by PLF and 20 treated by PDR). The overall clinical outcomes were comparable in both populations (88% in the PDR and 80% in PLF group 1), with a larger proportion of excellent results (56% vs. 10%) and of return to work in the PDR group. Radiological quantitative analysis highlighted stationary evolution and comparable outcomes for the two groups, except for vertebral slip evolution and adjacent level degeneration rate. Abnormal kinematic patterns outlined for PLF patients 20% of pseudarthrosis and 42% of adjacent levels hypermobility and for PDR ones low mobility for the levels adjacent to instrumented vertebra in 40% of cases. Quantified analysis of biomechanical parameters interpreted altogether with clinical outcome, complications and economic burden of the patient, provided accurate objective data for a better appreciation of global outcome, allowing for a preliminary view on long-term outcomes after PDR in adult low-grade isthmic spondylolisthesis, which were not presented in literature until now. 相似文献
86.
David H. Wilson Catherine R. Chittleborough Kerry Kirke Janet F. Grant Richard E. Ruffin 《Sozial- und Pr?ventivmedizin》2004,13(5):406-412
Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36. 相似文献
87.
David A. Davis 《Canadian Medical Association journal》2004,171(2):149-150
88.
OBJECTIVE AND IMPORTANCE: Fusiform aneurysms of the vertebrobasilar arteries that progressively enlarge causing symptomatic brainstem compression are dangerous and their treatment is difficult. A patient with such an aneurysm treated successfully with staged, microsurgical occlusions of the proximal vertebral arteries is described, and the literature pertaining to this rare condition is briefly reviewed. CLINICAL PRESENTATION: A 48-year-old man with a fusiform basilar trunk aneurysm of uncertain etiology presented initially with transient ischemic attacks (TIAs) of the posterior circulation that ceased with anticoagulation. Four years later he presented again with progressive ataxia, dysphagia and dysphonia due to considerable enlargement of the aneurysm causing brainstem compression. INTERVENTION: Staged microsurgical vertebral artery occlusions proximal to the aneurysm were performed. The second (left) vertebral artery was clipped only after the patient passed its temporary occlusion with an endovascular test balloon. The aneurysm subsequently thrombosed, the distal basilar artery kept patent by a single (left) posterior communicating artery. The patient's clinical condition improved markedly over a number of months as the aneurysm mass atrophied. CONCLUSION: Giant vertebrobasilar aneurysms are rare but treacherous lesions, sometimes justifying aggressive management. Carefully selected patients with progressive and severe symptoms due to brainstem compression may tolerate proximal vertebral artery occlusions, provided there is adequate collateral flow to the basilar termination and all of its perforating branches. 相似文献
89.
Andrew F Shorr William L Jackson Brendan M Weiss Lisa K Moores 《Blood coagulation & fibrinolysis》2007,18(4):309-316
Multiple options exist for the prevention of deep vein thrombosis (DVT) in medical inpatients. We sought to determine the cost-effectiveness of low-molecular-weight heparin (LMWH) relative to unfractionated heparin (UFH) for DVT prevention in this setting. We conducted a cost-effectiveness analysis from the perspective of a third-party payer employing a decision model and literature-based estimates for inputs. In the base-case analysis, LMWH had little impact on the rate of DVT. Despite higher acquisition costs, however, LMWHs resulted in net savings. Routine use of LMWH saves approximately US$89 per patient. The lower rate of heparin-induced thrombocytopenia (HIT) with LMWH accounted for this differential. Univariate sensitivity analysis revealed the model was moderately sensitive to the odds ratio of HIT with LMWH and the cost of HIT. Multivariate sensitivity analysis confirmed the LMWH approach dominated financially. 'Worst-case' scenario modeling, where LMWH actually increased the risk for DVT, had little effect on the rate of HIT, and was substantially more costly than UFH, still demonstrated that LMWHs were economically superior. Monte-Carlo simulation indicated the 95% confidence interval around the estimate for savings with LMWH ranged from US$7 to US$373. We conclude that, despite their higher cost, LMWHs for thromboprophylaxis in medical patients result in savings. 相似文献
90.