Influence of the practice setting on diagnostic prediction rules using FENO measurement in combination with clinical signs and symptoms of asthma

Objectives: To evaluate the influence of the practice setting on diagnostic accuracy of fractional exhaled nitric oxide (FENO) for diagnosing asthma; and to develop prediction rules for diagnostic decision-making including clinical signs and symptoms (CSS). Setting: Patients from 10 general practices and 1 private practice of 5 pneumologists in ambulatory care. Participants: 553 patients, 57.9% female. Consecutive inclusion of diagnostic-naive patients suspected of suffering from obstructive airway disease. Exclusion criteria were respiratory tract infections within the last 6 weeks. Interventions: The index test was FENO measurement. Reference standard was the Tiffeneau ratio (forced expiratory volume in 1 s/vital capacity) or airway resistance as assessed by whole body plethysmography, with additional bronchoprovocation or bronchodilator testing. Primary and secondary outcome measures: Asthma as determined by pneumologists, who were blind to FENO measurement results. Prediction rules were derived from multiple logistic regression analysis. A freely available calculator that allows computing all combinations was developed. Results: The practice setting only had minor influence on sensitivities of FENO cut-off points. In the final model (n=472), allergic rhinitis, wheezing and previous medication were positively associated with asthma. Increasing age and recurrent respiratory tract infections were negatively associated. The area under the curve (AUC) of FENO (AUC=0.650; 95% CI 0.599 to 0.701) increased significantly (p30 ppb. Ruling out with FENO <16 ppb in patients <43 years was only possible without allergic symptoms when recurrent respiratory tract infections were present. Conclusions: FENO results should be interpreted in the context of CSS to enhance their diagnostic value in primary care. The final diagnostic model appears as a sound algorithm fitting well to the established diagnostic rules related to CSS of asthma. FENO appears more effective for ruling in asthma than for ruling it out

What patients really think about asthma guidelines : barriers to guideline implementation from the patients' perspective

Background: Treatment of asthma does not always comply with asthma guidelines (AG). This may be rooted in direct or indirect resistance on the doctors’ and/or patients’ side or be caused by the healthcare system. To assess whether patients’ concepts and attitudes are really an implementation barrier for AG, we analysed the patients’ perspective of a “good asthma therapy” and contrasted their wishes with current recommendations. Methods: Using a qualitative exploratory design, topic centred focus group (FG) discussions were performed until theoretical saturation was reached. Inclusion criteria were an asthma diagnosis and age above 18. FG sessions were recorded audio-visually and analysed via a mapping technique and content analysis performed according to Mayring (supported by MAXQDA®). Participants’ speech times and the proportion of time devoted to different themes were calculated using the Videograph System® and related to the content analysis. Results: Thirteen men and 24 women aged between 20 and 77 from rural and urban areas attended five FG. Some patients had been recently diagnosed with asthma, others years previously or in childhood. The following topics were addressed: (a) concern about or rejection of therapy components, particularly corticosteroids, which sometimes resulted in autonomous uncommunicated medication changes, (b) lack of time or money for optimal treatment, (c) insufficient involvement in therapy choices and (d) a desire for greater empowerment, (e) suboptimal communication between healthcare professionals and (f) difficulties with recommendations conflicting with daily life. Primarily, (g) participants wanted more time with doctors to discuss difficulties and (h) all aspects of living with an impairing condition. Conclusions: We identified some important patient driven barriers to implementing AG recommendations. In order to advance AG implementation and improve asthma treatment, the patients’ perspective needs to be considered before drafting new versions of AG. These issues should be addressed at the planning stage. Trial registration: DRKS00000562 (German Clinical Trials Registry)

Анализ чувствительности влияния геологических неопределенностей при моделировании дискретной сети трещин на разработку месторождений на примере нефтяного месторождения Томской области

Объектом исследования является геологические неопределенности при построении дискретной сети трещин. Цель работы: важность понимания влияния геологических неопределенностей при построении дискретной сети трещин на прогнозирование добычи. В процессе исследования проводился анализ чувствительности геологических неопределенностей при построении дискретной сети трещин. В результате исследования выявлены количественные зависимости геологических неопределенностей при построении дискретной сети трещин с параметрами разработки месторождения Томской области (КИН, обводненность), которые помогут более корректно прогнозировать добычу углеводородов. Область применения: прогнозирование добычи. Значимость работы оптимизация параметров для построения корректной гидродинамической модели.Subject of investigation is geological uncertainties on DFN model construction. Aim of work – evaluate geological uncertainties on DFN model construction impact on production forecasts. During investigation realized sensitivity analysis of geological uncertainties on DFN model construction. Result of investigation is estimation recovery factor and water cut, as a function of fracture intensity, fracture length and orientation of fracture reservoir on real field data. Field of application: production forecasts. Significance: optimization of simulation model and more correct forecasts. Future work associated with acquisition new input data and increasing quality of DFN