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991.
Periodontal research typically relies on clinical examiners to assess variables such as gingival inflammation, plaque scores or probing depths as a means of determining treatment outcomes or for performing group comparisons. The quality of the gathered information is dependent, to a large extent, on the skills of the examiner(s) and on the validity of the assessment methods that are used. Attempts have been made to increase the objectivity of periodontal assessments, for example by introducing scoring systems for gingival inflammation, but within these systems there is often considerable scope for variation when interpreting the scoring criteria, leading to subjectivity when assigning scores to individual periodontal sites. This has led to an awareness of the importance of examiner alignment and assessment to improve the data quality by standardizing techniques and improving examiner reliability. Examiner alignment and assessment is used in preference to the term 'examiner calibration' because calibration implies comparison with an accurate or 'gold' standard, which is not available in periodontal research. In this review, we consider the historical perspective that led to the development of clinical scoring systems for periodontal research using gingival inflammation as an example. A clinical protocol for undertaking examiner alignment and assessment is presented, and we review the common sources of error and bias that can lead to difficulties in aligning examiners, and consider how they can be eliminated. It is particularly important that subjects who are recruited to the examiner alignment and assessment study present with a comparable level of disease to the subjects who will ultimately be recruited to the planned clinical trial. Another challenge in examiner alignment and assessment is applying appropriate statistical tests to assess the outcome of the alignment exercise. In the periodontal literature, the statistic kappa is frequently used to confirm an adequate degree of examiner agreement, but kappa is bound to significant restrictions when applied for this purpose. Through the use of case studies, we present different approaches to data analysis from calibration studies, focusing on continuous variables (such as probing depths and attachment levels) or ordinal data (such as gingival or plaque indices), to enable a correct, although frequently conservative, interpretation of data generated during examiner alignment and assessment studies. 相似文献
992.
Zeeshan G. Khattak Philip C.M. Benington Balvinder S. Khambay Lyndia Green Fraser Walker Ashraf F. Ayoub 《Journal of cranio-maxillo-facial surgery》2012,40(3):243-247
The quality of care delivered to 74 patients undergoing orthognathic surgery was assessed using a patient satisfaction questionnaire and data collected from hospital case records. Surgical complications, hospital services, patient satisfaction, and impact on quality of life, were the main aspects considered. The majority of patients reported that their treatment objectives had been achieved and that they were satisfied with the quality of care provided. The main concern of the patients regarding the clinic was the waiting time before an appointment could be offered. Eating and breathing difficulties and low mood after surgery were the main reported complications. Sixty-three patients experienced post-operative weight loss. The importance of a nutritious, high calorie soft diet should be emphasised and the use of menthol inhalations following maxillary osteotomies should be considered more frequently. Clinicians should be aware of post-operative low mood, which may require psychological support. We developed a sensitive assessment battery with comprehensive parameters to audit quality of orthognathic surgery service, and recommend that a similar approach should be considered by teams which undertake management of orthognathic patients. 相似文献
993.
994.
Moss WJ Norris DE Mharakurwa S Scott A Mulenga M Mason PR Chipeta J Thuma PE;Southern Africa ICEMR Team 《Acta tropica》2012,121(3):207-211
The burden of malaria has decreased dramatically within the past several years in parts of sub-Saharan Africa, including regions of Southern Africa. Important to effective regional malaria control in Southern Africa is the appreciation that the reductions in malaria have not been achieved uniformly, with some countries experiencing resurgence. Understanding the reasons for sustained low-level malaria transmission in the face of control efforts, why malaria control efforts have not been successful in particular epidemiological settings and the epidemiological and transmission patterns following resurgence are critical to improving further malaria control and possible elimination. The overall goal of the International Center of Excellence for Malaria Research in Southern Africa is to contribute to regional malaria control efforts that can be sustained beyond the duration of the project. This goal will be achieved through a combination of: (1) state-of-the-art research on malaria epidemiology, vector biology and the genetics of the malaria parasite in three different epidemiological settings; (2) collaborations with national malaria control programs to develop locally adapted and sustainable control strategies; and (3) training, career development and capacity building at research institutions throughout the region. 相似文献
995.
996.
T Li A Ito X Chen C Long M Okamoto F Raoul P Giraudoux T Yanagida M Nakao Y Sako N Xiao PS Craig 《Acta tropica》2012,124(2):152-157
Taeniasis refers to the infection with adult tapeworms of Taenia spp. in the upper small intestine of humans, which is also a cause of cysticercosis infection in either both humans and/or animals. Currently the most commonly applied anthelminthics for treatment of taeniasis are praziquantel and niclosamide. Praziquantel is very effective, but has the risk of induction of epileptic seizures or convulsions in carriers with asymptomatic concurrent neurocysticercosis. In contrast, niclosamide is safe and effective, but is not readily available in many endemic countries including China. In the current community-based study, we assessed the curative effect of either pumpkin seeds or areca nut extract alone in taeniasis, and also looked at synergistic effects of these two herb drugs on tapeworms. In the study group with the pumpkin seed/areca nut extract treatment, 91 (79.1%) of 115 suspected taeniasis cases (with a history of expulsion of proglottids within the previous one year) released whole tapeworms, four (3.5%) expelled incomplete strobila, and no tapeworms or proglottids were recovered in the remaining 20 cases. In these 115 persons, 45 were confirmed as taeniasis before treatment by microscopy and/or coproPCR. Forty (88.9%) of 45 confirmed cases eliminated intact worms following treatment. The mean time period for complete elimination of tapeworms in 91 taeniasis cases was 2h (range 20min to 8h 30min), and 89.0% (81) of 91 patients discharged intact worms within 3h after drug administration. In Control Group A with treatment of pumpkin seeds alone, 75.0% (9/12) of confirmed taeniasis cases expelled whole tapeworms, but the mean time period for complete elimination was about 14h 10min (range 3h 20min to 21h 20min), which was much longer than that (2h) for the study group, whereas in Control Group B treated with areca nut extract alone, only 63.6% (7/11) of taeniasis cases discharged whole tapeworms, and the mean time period was 6h 27min (range 1-22h). Mild side effects included nausea and dizziness in about 46.3% of patients with the pumpkin seeds/areca nut extract treatment, but all discomforts were transient and well tolerated. In conclusion, a synergistic effect of pumpkin seed and areca nut extract on Taenia spp. tapeworms was confirmed in the current study, primarily in producing an increased rate of effect on tapeworm expulsion (average time 2h for combination vs 6-21h for individual extracts). The pumpkin seed/areca combined treatment was indicated to be safe and highly effective (89%) for human taeniasis. 相似文献
997.
998.
999.
The antiphospholipid syndrome (APS) is defined by the persistent presence of antiphospholipid antibodies in patients with a history of thrombosis and/or pregnancy morbidity, including fetal loss. APS is an autoimmune disease with a confusing name because the pathologic auto-antibodies are shown to be directed against the plasma protein β(2)-glycoprotein I and not against phospholipids. In fact, auto-antibodies that recognize phospholipids themselves are not associated with thrombosis but with infectious diseases. One of the intriguing questions is why autoantibodies against β(2)-glycoprotein I are so commonly found in both patients and the healthy. Several potential mechanisms have been suggested to explain the increased thrombotic risk in patients with these autoantibodies. In this overview, we will summarize our knowledge on the etiology of the autoantibodies, and we will discuss the evidence that identify autoantibodies against β(2)-glycoprotein I as the culprit of APS. 相似文献
1000.
Campbell PJ Maclean C Beer PA Buck G Wheatley K Kiladjian JJ Forsyth C Harrison CN Green AR 《Blood》2012,120(7):1409-1411
Essential thrombocythemia, a myeloproliferative neoplasm, is associated with increased platelet count and risk of thrombosis or hemorrhage. Cytoreductive therapy aims to normalize platelet counts despite there being only a minimal association between platelet count and complication rates. Evidence is increasing for a correlation between WBC count and thrombosis, but prospective data are lacking. In the present study, we investigated the relationship between vascular complications and 21 887 longitudinal blood counts in a prospective, multicenter cohort of 776 essential thrombocythemia patients. After correction for confounding variables, no association was seen between blood counts at diagnosis and future complications. However, platelet count outside of the normal range during follow-up was associated with an immediate risk of major hemorrhage (P = .0005) but not thrombosis (P = .7). Elevated WBC count during follow-up was correlated with thrombosis (P = .05) and major hemorrhage (P = .01). These data imply that the aim of cytoreduction in essential thrombocythemia should be to keep the platelet count, and arguably the WBC count, within the normal range. This study is registered at the International Standard Randomized Controlled Trials Number Registry (www.isrctn.org) as number 72251782. 相似文献