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101.
Background. Controlling costs and achieving health care quality improvements require the participation of activated and informed consumers and patients.
Objectives. We describe a process for conceptualizing and operationalizing what it means to be "activated" and delineate the process we used to develop a measure for assessing "activation," and the psychometric properties of that measure.
Methods. We used the convergence of the findings from a national expert consensus panel and patient focus groups to define the concept and identify the domains of activation. These domains were operationalized by constructing a large item pool. Items were pilot-tested and initial psychometric analysis performed using Rasch methodology. The third stage refined and extended the measure. The fourth stage used a national probability sample to assess the measure's psychometric performance overall and within different subpopulations.
Study Sample. Convenience samples of patients with and without chronic illness, and a national probability sample ( N =1,515) are included at different stages in the research.
Conclusions. The Patient Activation Measure is a valid, highly reliable, unidimensional, probabilistic Guttman-like scale that reflects a developmental model of activation. Activation appears to involve four stages: (1) believing the patient role is important, (2) having the confidence and knowledge necessary to take action, (3) actually taking action to maintain and improve one's health, and (4) staying the course even under stress. The measure has good psychometric properties indicating that it can be used at the individual patient level to tailor intervention and assess changes.  相似文献   
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Reasons for patient non-entry in randomized clinical trials (RCTs) assessing oncologic treatment modalities are not well documented in the literature. We have prospectively recorded reasons for RCT non-entry in breast cancer patients at St. Michael's Hospital, Toronto. From September 1984 to November 1989, 592 consecutive patients were evaluated through the clinical trials office. One hundred six out of the 592 patients were placed into a RCT (17.9%). Protocol ineligibilities accounted for 273 non-entries (46.1%) and protocol eligible but not entered patients accounted for 213 (36.0%) non-entries. The most common reason for protocol ineligibility was advanced age (94 patients). The most common reason for protocol eligible but not entered patients was patient refusal (148 patients). A total of 272 patients in both non-entered groups were identified as having reasons for non-entry that were potentially correctable. In summary, protocol ineligibilities account for the majority of non-entered patients, but patient refusal accounted for the single largest group of potentially correctable non-entries. More dissemination about the merit of RCTs in the lay press and amongst primary care physicians must take place if we are to expediently and efficiently answer important oncologic questions.  相似文献   
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Goiters can be detected in about 5 per cent of school-aged children. Goiters appearing during childhood are the result of distinct diseases and should be investigated rather than attributed to "physiologic hyperplasia." The etiology of the diffuse goiter can often be established by clinical evaluation, performing thyroid function tests, and measurement of serum thyroid antibodies. Unlike diffuse goiters, thyroid nodules frequently require tissue examination to exclude malignancy. The goal in evaluating children with nodular goiters is to be as selective as possible in submitting children to surgery without missing cases of cancer. The decision to perform an open biopsy should be based on detecting increased risk for cancer in the medical history, physical examination, or laboratory tests as outlined in Figure 1. Ultrasonography and fine-needle aspiration of nodules are two new methods that aid in the selection of patients for surgery or a trial of thyroid hormone suppression.  相似文献   
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Twenty-eight patients with demonstrated chronic renal vein thrombosis were studied. In seven, only small venous channels were involved; in 21, both small and large veins were thrombosed. A constellation of findings occurred with such frequency in these patients that we believe it virtually diagnostic of renal venous obstruction. These findings include the nephrotic syndrome, great variability in proteinuria and glomerular filtration rate, pulmonary embolization, sterile pyuria, hematuria, hyperchloremic acidosis, decreased renal tubular threshold for glucose and increased fibrin degradation products. These findings are an indication for definitive angiographic and biopsy procedures. Prolonged anticoagulant therapy was generally very effective.  相似文献   
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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
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