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31.

Background

Definitive diagnosis of occult scaphoid fractures remains difficult. We tested the null hypothesis that, for diagnosis of true fractures among suspected scaphoid fractures, computed tomography (CT) reformations along the long axis of the scaphoid have the same accuracy as reformations made relative to the anatomical planes of the wrist.

Methods

In a prospective trial, 34 patients with a suspected scaphoid fracture underwent CT scanning within 10 days after trauma. CT reformations along the long axis of the scaphoid (CT-scaphoid) and along planes relative to the wrist (CT-wrist) were made. We used radiographs obtained 6 weeks after injury as the reference standard for a true fracture. A blinded panel including two surgeons and one radiologist came to a consensus diagnosis for each reformation plane.

Results

The reference standard showed six fractures of the scaphoid (prevalence, 18 %). Using CT-wrist, a scaphoid fracture was diagnosed in five patients (15 %), with three false positive, four false negative and two true positive diagnoses. Using CT-scaphoid, a scaphoid fracture was diagnosed in five patients (15 %), with one false positive, two false negative and four true positive results. Sensitivity, specificity and accuracy were 33, 89 and 79 % for CT-wrist and 67, 96 and 91 % for CT-scaphoid, respectively. This resulted in positive predictive values of 36 % for CT-wrist and 76 % for CT-scaphoid. Negative predictive values were 87 % for CT-wrist and 94 % for CT-scaphoid. No significant differences were found with the number of patients available.

Conclusions

For diagnosis of true fractures among suspected scaphoid fractures, the diagnostic performance characteristics of CT scans reformatted along the long axis of the scaphoid were better than CT scans in the planes of the wrist, but the differences were not significant.  相似文献   
32.
The response to lepromin and Kveim antigens was compared and studied in 15 leprosy patients who were tuberculin negative. Of the 11 lepromin positive tuberculoid patients, 4 were Kveim positive, 1 was equivocal, and the rest were negative. Of the four lepromin negative lepromatous patients, one gave a positive Kveim test while the other three were negative. It has been shown that false-positive Kveim reactions are found in a higher percentage of South Indian leprosy patients than in those of other backgrounds, such as Japanese and Malaysian Chinese patients. It is also suggested that no definite relationship exists between the reaction of leprosy patients to lepromin and Kveim antigens. We further suggest that the anergy exhibited by lepromatous patients to the antigen of M. leprae is specific, as evidenced by the positive Kveim response in one lepromatous patient.  相似文献   
33.
This study determined inter- and intra-observer reliability for measurement of the angles of Böhler and Gissane, for the decision between surgical or conservative management and for the three mostly used classification systems for calcaneal fractures with the use of 2D-CT imaging versus 2D- and 3D-CT imaging.  相似文献   
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ContextIt remains unclear whether there would be societal support for a lifestyle criterion for the healthcare priority setting. This study examines the viewpoints of experts in healthcare and the public regarding support for a lifestyle‐related decision criterion, relative to support for the currently applied criteria, in the healthcare priority setting in the Netherlands.MethodsWe conducted a Q methodology study in samples of experts in healthcare (n = 37) and the public (n = 44). Participants (total sample N = 81) ranked 34 statements that reflected currently applied decision criteria as well as a lifestyle criterion for setting priorities in healthcare. The ranking data were subjected to principal component analysis, followed by oblimin rotation, to identify clusters of participants with similar viewpoints.FindingsWe identified four viewpoints. Participants with Viewpoint 1 believe that treatments that have been proven to be effective should be reimbursed. Those with Viewpoint 2 believe that life is precious and every effort should be made to save a life, even when treatment still results in a very poor state of health. Those with Viewpoint 3 accept government intervention in unhealthy lifestyles and believe that individual responsibility should be taken into account in reimbursement decisions. Participants with Viewpoint 4 attribute importance to the cost‐effectiveness of treatments; however, when priorities have to be set, treatment effects are considered most important. All viewpoints were supported by a mix of public and experts, but Viewpoint 1 was mostly supported by experts and the other viewpoints were mostly supported by members of the public.ConclusionsThis study identified four distinct viewpoints on the healthcare priority setting in the Netherlands, each supported by a mix of experts and members of the public. There seems to be some, but limited, support for a lifestyle criterion—in particular, among members of the public. Experts seem to favour the decision criteria that are currently applied. The diversity in views deserves attention when policymakers want to adhere to societal preferences and increase policy acceptance.  相似文献   
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In a general practice based population 76% of 530 children inhaling asthma medication inhaled correctly. However, important differences among inhalers were found. Children with a pressurized metered-dose inhaler without a spacer device performed worst, with only 22% inhaling without essential errors. At a second evaluation of the inhaler technique, one year after the first assessment, performances with a new device were more often incorrect versus the unchanged devices (21.1% and 10.8%, respectively; p = 0.01). Providing children with a new device should be carefully controlled over time especially because these children are error prone.  相似文献   
38.
Blink‐related ocular activity is a major source of artifacts in electroencephalogram (EEG) data. Independent component analysis (ICA) is a well‐known technique for the correction of such ocular artifacts, but one of the limitations of ICA is that the ICs selected for removal contain not only ocular activity but also some EEG activity. Straightforward removal of these ICs might, therefore, lead to a loss of EEG data. In this article a method is proposed to separate blink‐related ocular activity from actual EEG by combining ICA with a novel technique, empirical mode decomposition. This combination of two techniques allows for maximizing the retention of EEG data and the selective removal of the eyeblink artifact. The performance of the proposed method is demonstrated with simulated and real data.  相似文献   
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40.
Many chronic obstructive pulmonary disease (COPD) patients use their inhaler ineffectively and there is a trend towards increased inhaler resistance. We wanted to answer two questions: Is there a difference in preference and ease of use between Diskus (DK) and Handihaler (HH)? How acceptable are inhalation resistances? Sixty COPD patients, naive to DK and HH, but experienced in the use of other inhalers, had to read the instruction leaflet and demonstrate their inhalation technique. If errors were made, instruction was given and inhalation technique was checked again. Patients had to state a preference for DK or HH. Subsequently they inhaled through a range of resistances and scored the acceptability. There was no difference in the number of instructions needed for both inhalers. One third inhaled perfectly after reading the instruction leaflet, which increased to 85% after one instruction. More patients preferred the DK (43) than the HH (16). With decreasing resistance acceptability increases, but it reaches a plateau. Patients have a clear preference for the DK. There is no difference in the number of instructions needed to obtain a perfect inhalation technique, but for some patients one instruction is not enough. The trend to increase the resistance of inhalers has reached a critical point with regard to acceptability.  相似文献   
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