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91.
BACKGROUND: The evaluation and interpretation of the results from blood tests measuring specific immunoglobulin E (IgE) antibody concentration is currently made using the dichotomized result from the test despite a quantitative result is obtained. It has been shown that different levels of IgE antibodies, assessed by blood test and skin prick test, may have a relation to presence of symptoms, implying that there is more information in a quantitative result than in the dichotomous--positive or negative. OBJECTIVE: To investigate the clinical utility of quantification of IgE antibodies in the diagnosis of allergic patients and whether such procedure has any advantage to the presently dichotomously used sensitivity and specificity at a fixed cut-off. METHODS: Data from a previously published study (R. Paganelli, I.J. Ansoteugi, J. Sastre, C.-E. Lange, M.H.W.M. Roovers, H. de Groot, N.B. Lindholm, P.W. Ewan, Allergy, 1998; 53) analysing diagnosis of allergic patients in four different clinics were re-evaluated. In the original study consecutive patients with suspected IgE-mediated allergy had been examined and evaluated according to the clinical routine at each clinic, using case history, physical examination, skin tests and laboratory tests, except the test to be evaluated, and given a "doctors' allergen-specific diagnosis" as positive or negative. In the present study the relation between "doctors' allergen-specific diagnosis", expressed as pos/neg, and the quantitative levels of specific IgE antibody concentration was analysed using a logistic regression model. This presentation of results was also compared with the more common characteristics of sensitivity and specificity, and also with Receiver-operator characteristics (ROC) curves. RESULTS: The used logistic model described the relationship between allergen-specific diagnosis in each study and the levels of IgE antibodies. The shape of the curve illustrated the physicians' disposition for a positive diagnose in the study, in relation to the specific IgE antibody level. Differences in the shape of the curve was found both between allergens within clinics and between clinics for the same allergen. No association could be demonstrated between prevalence and shape of the curve. CONCLUSIONS: Conventional sensitivity/specificity figures or ROC concepts only use the qualitative statement of whether IgE is present or not. A risk assessment using the quantitative level of IgE antibody to an allergen increases the utility of the information in clinical context compared with a qualitative statement of whether IgE is present or not. The quantification demonstrated the link between specific IgE antibodies and allergic reactions. The use of objective, well performing quantitative tests should help improve diagnostic accuracy and might provide a way for the patient to understand and manage his or her daily situation and risk for reactions.  相似文献   
92.
Examined the utility of a new parent-report measure designedspecifically for pediatric inpatients, the Behavioral Upsetin Medical Patients-Revised (BUMP-R). The BUMP-R was administeredto 151 mothers of hospitalized children ages 4–12 yearsthe day following the child's hospital admission. The BUMP-Rdemonstrated good internal consistency and a factor analysisrevealed four factors identified as negativity/agitation, amiability,dysphoria, and noncom-pliance. Children exhibiting behavioraldistress at home were more likely to experience adjustment problemsupon hospitalization. Demographic and illness-related variableswere not substantial risk factors for hospital adjustment difficulties.  相似文献   
93.
Appropriate deployment of technological innovation contributes to improvement in the quality of healthcare delivered, containment of cost, and an increased access to the healthcare system. Hospitals have been allocating a, significant portion of their resources to procuring and managing capital assets; they are continously faced with demands for new medical equipment and are, asked to manage existing inventory for which they are not well prepared. To objectively manage their investment, hospitals are developing medical technology management programmes that need pertinent information and methods for new equipment planning as well as for reduction in the ownership costs of existing equipment. Clinical engineers can identify new medical equipment, review their institution's technological position, develop equipment-selection criteria, supervise installations and monitor postprocurement performance to meet their hospital's programme's objectives. This programme, together with cost accounting analysis, will objectively guide the capital assets decisionmaking process. The result of systematic planning and execution, the programme will assure the lowest life-cycle costs at the best performance. The clinical engineer's skills and expertise are needed to facilitate the adoption of an objective methodology for implementing the programme, thus improving the match between the hospital's needs and budget projections, equipment performance and cost of ownership.  相似文献   
94.
The role of intraoperative frozen section in certain organ systems such as the thyroid continues to be problematic. In many cases, diagnoses are deferred or nonhelpful—“follicular lesion.” In the modern era, the widespread use of preoperative aspiration biopsy has allowed for more careful selection of patients who undergo thyroid surgery. In many cases, the fine-needle-aspiration (FNA) biopsy diagnosis can be definitive or can guide the specific surgical procedure. The literature supports our approach, which is summarized as follows: Intraoperative consultation is not needed on the intrathyroidal nodule if a preoperative FNA was definitive for papillary carcinoma. Frozen section is of no value in the intraoperative diagnosis of lesions diagnosed on FNA as “follicular neoplasm” or “Hürthle cell neoplasm” because the characterization of these lesions requires detailed analysis of the tumor capsule for the demonstration of capsular and/or vascular invasion—an analysis that is not practical in the intraoperative setting. Finally, intraoperative consultation including frozen section and intraoperative cytologic examination is most useful in those cases that are diagnosed as suspicious for papillary carcinoma by FNA, because the assessment of nuclear features needed for the definitive diagnosis is possible with intraoperative techniques in a significant number of cases.  相似文献   
95.
Zusammenfassung Anhand einer prospektiven, auslesefreien Serie von 22 Patienten mit perforierten Ulcera im Gastroduodenalbereich verweisen wir auf die begrenzte diagnostische Aussagekraft einfacher anamnestischer, klinischer und radiologischer Daten. Lediglich bei acht Patienten (36%) ergaben sich wesentliche Indizien aus Krankengeschichte und Aufnahmebefund. Bei 16 Patienten (73%) verriet die Thoraxübersichtsaufnahme durch Nachweis einer subphrenischen Luftsichel eine Perforation im Magen-Darm-Trakt. Die Ultraschalluntersuchung wird als bedeutungsvolle Ergänzungsmethode vor allem in der diagnostischen Abklärung radiologisch negativer Ulcusperforationen vorgestellt und diskutiert. Dabei werden die sonographisch faßbare flüssigkeitsbedingte Magendistension sowie das Magenwandödem als unspezifische Kriterien gewertet. Der Objektivierung einer pathologischen Magenkokarde kommt bei gleichzeitigem Nachweis freier Luft und/oder extraluminärer Ingesta sowie freier echoloser Transsudatflüssigkeit pathognomonische Beweiskraft zu. Selbige Ultraschallkriterien erlaubten im einschlägigen Krankengut bei 16 Patienten (73%) eine definitive Diagnose und erfaßte 4 Patienten mit negativem Röntgen. Die kombinierte Analyse radiologischer und sonographischer Befunde führte somit bei 20 Patienten (91 %) unverzüglich zur korrekten Diagnose.
Perforated peptic ulcer: Diagnosis and assessment by sonography
Summary In a prospective unselected series of 22 patients with perforated gastroduodenal ulcers the diagnostic efficacy of clinical and radiologic data was modest. In eight patients only (36%), clinical data yielded sufficient evidence; in 16 patients (73%), plain X-ray demonstrated subphrenic gas. Sonography was proven to be a major advance, especially rewarding in the diagnosis of perforations with negative plain X-ray. Gastric distention and stomach wall edema are unspecifc sonographic criteria, whereas objectivation of a pathologic stomach cockade in the presence of free gas, extraluminary ingesta or echofree fluid in the peritoneal cavity are pathognomonic data. These criteria yielded a definite diagnosis in 16 patients (73%) including four patients with negative X-ray. The combined analysis of radiologic and sonographic findings yielded an immediate correct diagnosis in 20 patients (91%).
  相似文献   
96.
拒绝上学(SR)是儿童常见的心理行为问题之一,主要表现为儿童不愿上学或对学习、学校不感兴趣,甚至完全拒绝去学校。目前越来越多研究表明大多数拒绝上学儿童伴有焦虑、抑郁等情绪问题,对其学业、家庭、人际关系等各方面产生广泛且负面的影响。本文主要综述儿童拒绝上学的定义、评估方法、病因、治疗及预后,有助于临床医生进一步探究拒绝上学儿童的病因并及时地进行评估与干预,帮助其改善临床结局,尽早重返校园。  相似文献   
97.
王蓉  刘盼  任兴权  周丽  赵俊 《现代预防医学》2022,(14):2646-2651
目的 了解酒泉市戈壁设施种植的番茄、葫芦、黄瓜、辣椒、豆角中铅、砷、汞、镉的污染状况,评估人体摄入后的健康风险。方法 利用国家标准检验方法,在酒泉市总寨和东洞戈壁农业产业园区采集检测274份主栽蔬菜中铅、砷、汞、镉含量,结合单因子污染指数和内梅罗污染指数法对蔬菜受重金属污染的程度进行评价,利用靶标污染系数法对蔬菜中重金属对人体的健康风险进行评估。结果 274份蔬菜中铅、砷、汞和镉的含量范围分别为0~0.050 1 mg/kg、0~0.053 8 mg/kg、0~0.001 0 mg/kg和0~0.048 8 mg/kg,平均含量分别为0.010 3、0.010 3、0.000 2和0.008 7 mg/kg,均未超出国家标准规定的食品中污染物限量。5种蔬菜中4种重金属的污染指数均低于0.7,靶标危害系数均小于1。结论 酒泉市总寨和东洞戈壁农业产业园区主栽的5种蔬菜受铅、砷、汞、镉污染程度较轻,属于清洁水平,处于安全级别,膳食摄入风险较低。对比其它地区蔬菜,酒泉戈壁设施蔬菜中重金属含量总体不高,与有机设施蔬菜基地结果接近。  相似文献   
98.
《Value in health》2022,25(6):992-1001
ObjectivesWith complex health technologies entering the market, methods for health technology assessment (HTA) may require changes. This study aimed to identify challenges in HTA of complex health technologies.MethodsA survey was sent to European HTA organizations participating in European Network for HTA (EUnetHTA). The survey contained open questions and used predefined potentially complex health technologies and 7 case studies to identify types of complex health technologies and challenges faced during HTA. The survey was validated, tested for reliability by an expert panel, and pilot tested before dissemination.ResultsA total of 22 HTA organizations completed the survey (67%). Advanced therapeutic medicinal products (ATMPs) and histology-independent therapies were considered most challenging based on the predefined complex health technologies and case studies. For the case studies, more than half of the reported challenges were “methodological,” equal in relative effectiveness assessments as in cost-effectiveness assessments. Through the open questions, we found that most of these challenges actually rooted in data unavailability. Data were reported as “absent,” “insufficient,” “immature,” or “low quality” by 18 of 20 organizations (90%), in particular data on quality of life. Policy and organizational challenges and challenges because of societal or political pressure were reported by 8 (40%) and 4 organizations (20%), respectively. Modeling issues were reported least often (n = 2, 4%).ConclusionsMost challenges in HTA of complex health technologies root in data insufficiencies rather than in the complexity of health technologies itself. As the number of complex technologies grows, the urgency for new methods and policies to guide HTA decision making increases.  相似文献   
99.
《Value in health》2022,25(3):331-339
ObjectivesClinical artificial intelligence (AI) is a novel technology, and few economic evaluations have focused on it to date. Before its wider implementation, it is important to highlight the aspects of AI that challenge traditional health technology assessment methods.MethodsWe used an existing broad value framework to assess potential ways AI can provide good value for money. We also developed a rubric of how economic evaluations of AI should vary depending on the case of its use.ResultsWe found that the measurement of core elements of value—health outcomes and cost—are complicated by AI because its generalizability across different populations is often unclear and because its use may necessitate reconfigured clinical processes. Clinicians’ productivity may improve when AI is used. If poorly implemented though, AI may also cause clinicians’ workload to increase. Some AI has been found to exacerbate health disparities. Nevertheless, AI may promote equity by expanding access to medical care and, when properly trained, providing unbiased diagnoses and prognoses. The approach to assessment of AI should vary based on its use case: AI that creates new clinical possibilities can improve outcomes, but regulation and evidence collection may be difficult; AI that extends clinical expertise can reduce disparities and lower costs but may result in overuse; and AI that automates clinicians’ work can improve productivity but may reduce skills.ConclusionsThe potential uses of clinical AI create challenges for health technology assessment methods originally developed for pharmaceuticals and medical devices. Health economists should be prepared to examine data collection and methods used to train AI, as these may impact its future value.  相似文献   
100.
《Value in health》2022,25(1):59-68
ObjectivesWe investigated how health technology assessment (HTA) organizations around the world have handled drug genericization (an allowance for future generic drug entry and subsequent drug price declines) in their guidelines for cost-effectiveness analyses (CEAs). We also analyzed a large sample of published CEAs to examine prevailing practices in the field.MethodsWe reviewed 43 HTA guidelines to determine whether and how they addressed drug genericization in their CEAs. We also selected a sample of 270 US-based CEAs from the Tufts Medical Center’s CEA Registry, restricting the sample to studies on pharmaceuticals published from 1991 to 2019 and to analyses taking a lifetime time horizon. We determined whether each CEA examined genericization (and if so, whether in base case or sensitivity analyses), and how inclusion of genericization influenced the estimated incremental cost-effectiveness ratios.ResultsFourteen (33%) of the 43 HTA guidelines mention genericization for CEAs and 4 (9%) recommend that base case analyses include assumptions about future drug price changes due to genericization. Most published CEAs (95%) do not include assumptions about future generic prices for intervention drugs. Only 2% include such assumptions about comparator drugs. Most studies (72%) conduct sensitivity analyses on drug prices unrelated to genericization.ConclusionsThe omission of assumptions about genericization means that CEAs may misrepresent the long run opportunity costs for drugs. The field needs clearer guidance for when CEAs should account for genericization, and for the inclusion of other price dynamics that might influence a drug’s cost-effectiveness.  相似文献   
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