81 research outputs found

    An evaluation of unit nonresponse bias in the Italian Households Budget Survey

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    Die Auswirkungen von Antwortverweigerung sind in der Literatur zur Umfrageforschung vielfach diskutiert worden. Antwortverweigerung fĂŒhrt zu einer Erhöhung der Stichprobenvarianz, deren Ausmaß ĂŒber die SchĂ€tzung der durch Antwortverweigerung verursachten Verzerrung gemessen werden kann. Wenn Befragte nur unvollkommen kooperieren, fĂŒhrt dies zu ungenauen oder unvollstĂ€ndigen Informationen, die nicht zum Zweck einer SchĂ€tzung herangezogen werden können. Istat streicht seit 1991 alle Haushalte mit inkompatiblen Daten fĂŒr Ausgaben und Einkommen aus seiner Stichprobe. Die Verfasser bezeichnen diese Gruppe als "unzuverlĂ€ssige Respondenten". Solche Daten eignen sich zwar nicht fĂŒr SchĂ€tzungen, sie erlauben jedoch RĂŒckschlĂŒsse auf die Gruppe der Antwortverweigerer. Dem liegt die Annahme zu Grunde, dass die Gruppe der unzuverlĂ€ssigen Respondenten eher der Gruppe der Antwortverweigerer Ă€hnelt als der Gruppe der Antwortenden. Die Verfasser berichten ĂŒber den Versuch, den durch Antwortverweigerung entstandenen Bias im Italian Household Budget Survey 1995 zu bestimmen. Hierzu wurde keine gesonderte Untersuchung der Nonrespondenten durchgefĂŒhrt. (ICEÜbers)"The effect of nonresponse is a crucial aspect which has received considerable attention in literature. Nonresponse causes an increase in sampling variance and the estimates of units nonresponse bias are useful to give a concrete measure of this increase. Scarce co-operation of respondents gives inaccurate or incomplete information, and this part of the answers can't be used in the estimation. Since 1991, Istat erases from its sample file all households with incompatible data on expenditure and income. The authors call this the 'UR (Unreliable Respondents) sub population'. UR data can't be used to build estimates, but can be used to give approximate information an NR. The idea is that, concerning behaviour, the NR population is more similar to UR than to R. The results of an attempt to evaluate unit nonresponse bias in the 1995 Italien Household Budget Survey (HBS) are shown in this paper. These results were obtained without performing a specific survey on nonrespondents." (author's abstract

    In tandem for cohesion?: synergies and conflicts between regional and agricultural policies of the European Union

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    Crescenzi, R., De Filippis, F. and Pierangeli, F. In tandem for cohesion? Synergies and conflicts between regional and agricultural policies of the European Union, Regional Studies. The paper analyses the financial allocations from the regional, rural development and agricultural policies of the European Union in order to assess their territorial coordination and synergies with the objective of territorial cohesion. Regression analysis is used to uncover the link between funds and territorial disadvantage for the 1994–2013 period. The analysis reveals that both coordination and compatibility with territorial cohesion have not always improved in response to major policy reforms. The territorial ‘vocation’ of overall community spending is weakly linked to its distribution among different policies, but it crucially depends upon appropriate ‘place-based’ allocation mechanisms

    Synergies and conflicts between EU policies and the objective of territorial cohesion

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    The paper looks at the overall structure of the European Union’s regional, agricultural and rural development policies in order to assess their coordination and synergies at the territorial level and their degree of compatibility with the objective of territorial cohesion. The regression analysis - covering the 20-year period 1994-2013, and approximately 90% of total Community expenditure - reveals that the compatibility of the various areas of Community policy in terms of the objectives of territorial cohesion has not progressed in a linear fashion over time. Shifting resources in the Community budget from one policy area to another does not, by itself, appear capable of guaranteeing virtuous paths in terms of territorial cohesion. The increase in the territorial ‘vocation’ of overall Community spending will, therefore, crucially depend upon the definition of appropriate allocative mechanisms and interventions, based upon the characteristics of each region and its ‘local’ needsRegional Policy, Regional Development, Rural Development, European Union

    Nonlinear beam self-imaging and self-focusing dynamics in a GRIN multimode optical fiber: theory and experiments

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    Beam self-imaging in nonlinear graded-index multimode optical fibers is of interest for many applications, such as implementing a fast saturable absorber mechanism in fiber lasers via multimode interference. We obtain an exact solution for the nonlinear evolution of first and second order moments of a laser beam carried by a graded-index multimode fiber, predicting that the spatial self-imaging period does not vary with power. Whereas the amplitude of the oscillation of the beam width is power-dependent. We have experimentally studied the longitudinal evolution of beam self-imaging by means of femtosecond laser pulse propagation in both the anomalous and the normal dispersion regime of a standard telecom graded-index multimode optical fiber. Light scattering out of the fiber core via visible fluorescence emission and harmonic wave generation permits us to directly confirm that the self-imaging period is invariant with power. Spatial shift and splitting of the self-imaging process under the action of self-focusing are also emphasized

    Health-Related Quality of Life in Patients with CVID Under Different Schedules of Immunoglobulin Administration: Prospective Multicenter Study

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    We assessed the health-related quality of life (HRQoL) in CVID adults receiving different schedules of immunoglobulin replacement therapy (IgRT) by intravenous (IVIG), subcutaneous (SCIG), and facilitated (fSCIG) preparations. For these patients, IgRT schedule was chosen after a period focused on identifying the most suitable individual option

    validation of a decision making strategy for systolic anterior motion following mitral valve repair

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    Low cardiac output syndrome and hypotension are dreadful consequences of systolic anterior motion (SAM) after a mitral valve (MV) repair. The management of SAM in the operating room remains controversial. We validate a recently suggested two-step management method and classification of this complication. This was a teaching hospital-based observational study. We validated a novel two-step conservative management method, consisting in intravascular volume expansion and discontinuation of inotropic drugs (step 1), and increasing the afterload by ascending aorta manual compression while administering esmolol e.v. (step 2). We also validate a novel classification of SAM: easy-to-revert (responding to step 1), difficult-to-revert (responding to step 2), or persistent. Fifty patients had an easy-to-revert while 26 had a difficult-to-revert SAM; 4 patients had a persistent condition (promptly diagnosed through our decisional algorithm) and underwent an immediate second pump run to repeat the mitral repair surgery. We confirmed that SAM after a repair of a degenerative MV is common and validated a simple two-step conservative management method that allows to clearly identify those few patients who require immediate surgical revision

    Venous endotelin-1 (ET-1) and brain natriuretic peptide (BNP) plasma levels during 6-month bosentan treatment for pulmonary arterial hypertension

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    Objective: Bosentan, an endothelin (ET) ETA-ETB receptors antagonist, is an effective therapy for idiopathic pulmonary arterial hypertension (PAH) and for PAH related to connective tissue disease (CTD). The aim of this study was to evaluate the behaviour of ET-1 and brain natriuretic peptide (BNP) venous plasma levels during a 6-month dual ET-1 receptor blockade and the potential influence of baseline ET-1 venous plasma levels on the clinical efficacy of bosentan. Setting and patients: Twenty-five patients with PAH (idiopathic n = 16, CTD n = 9) in WHO functional class II-III were included in this study. After initial evaluation, patients' WHO class, 6-minute walking-test (6MWT), ET-1 and BNP venous plasma levels were assessed at baseline and after 6-month bosentan therapy. To evaluate whether the ET-1 levels could influence the clinical response to bosentan, data were analyzed for the whole population which was stratified according to high and low ET-1 plasma levels (on the basis of the baseline median value of ET-1 plasma: Gr.1 18.7 pg/ml). Results: Study population included patients with moderate-severe PAH. After 6-month of treatment we observed a significant increase in 6MWT distance (from 435 ± 85) m to 467 ± 77 m, p > 0.001) and an improvement in WHO class (from 2.4 ± 0.5 to 2 ± 0.6 p > 0.01), with a significant decrease in BNP (from 87 ± 33 pg/ml to 67 ± 41 pg/ml, p = 0.006) and a trend towards lower ET-1 plasma levels (from 17.7 ± 5 pg/ml to 16 ± 6 pg/ml, p = ns). Improvement in effort tolerance (Δ distance) was not correlated to modification in ET-1 (ΔET-1) and BNP (ΔBNP) plasma levels, while we found a significant correlation between ΔET-1 and ΔBNP (r = 0.63, p = 0.0006). Analyzing the subpopulation, Gr.2 patients were older (Gr.1: 41 ± 10 years vs Gr.2: 50 ± 9 years, p = 0.04), had less effort capacity (6MWT distance, Gr.1: 469 ± 76 m, vs Gr.2: 398 ± 82 m, p = 0.03), and showed a trend towards higher BNP values (Gr.1: 82 ± 41 pg/ml vs Gr.2: 92 ± 23 pg/ml, p = 0.051), but no significant differences in pulmonary hemodynamics. After the 6-month treatment both groups showed a significant improvement in 6MWT (Gr.1: + 32 ± 24 m, Gr.2: + 32 ± 21 m p = 0.05) without differences between groups. WHO class had a trend towards lower class (Gr.1: - 0.5 ± 0.5, Gr.2: - 0.3 ± 0.4 p = 0.15) in both groups. BNP plasma levels showed a significant decrease only in Gr.2 (Gr.1: - 6 ± 41 pg/ml, Gr.2: - 34 ± 19 pg/ml p = 0.02); similarly ET-1 plasma levels showed a trend towards a decrease only in Gr.2 (Gr.1: 0.2 ± 4.6 pg/ml, Gr.2: - 3.8 ± 6.6 pg/ml p = 0.09). Conclusions: Our data confirm that bosentan is an effective therapy for patients with PAH. Its clinical efficacy (effort tolerance and NYHA) seems to be independent from baseline venous ET1 plasma levels. Bosentan therapy seems to elicit different patterns in ET-1 and BNP plasma levels, with decrease of the peptides only in patients with higher activation of the systemic endothelin system. Further studies are warranted to explore the potential impact of baseline ET-1 levels on the long-term effects (clinical worsening) of bosentan therapy. © 2008 Elsevier B.V. All rights reserved

    Minimal Extrathyroidal Extension in Predicting 1-Year Outcomes: A Longitudinal Multicenter Study of Low-to-Intermediate-Risk Papillary Thyroid Carcinoma (ITCO#4)

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    Background: The role of minimal extrathyroidal extension (mETE) as a risk factor for persistent papillary thyroid carcinoma (PTC) is still debated. The aim of this study was to assess the clinical impact of mETE as a predictor of worse initial treatment response in PTC patients and to verify the impact of radioiodine therapy after surgery in patients with mETE. Methods: We reviewed all records in the Italian Thyroid Cancer Observatory (ITCO) database and selected 2237 consecutive patients with PTC who satisfied the inclusion criteria (PTC with no lymph node metastases and at least 1 year of follow-up). For each case, we considered initial surgery, histological variant of PTC, tumor diameter, recurrence risk class according to the American Thyroid Association (ATA) risk stratification system, use of radioiodine therapy, and initial therapy response, as suggested by ATA guidelines. Results: At 1-year follow-up, 1831 patients (81.8%) had an excellent response, 296 (13.2%) had an indeterminate response, 55 (2.5%) had a biochemical incomplete response, and 55 (2.5%) had a structural incomplete response. Statistical analysis suggested that mETE (odds ratio [OR] 1.16, p=0.65), tumor size >2 cm (OR 1.45, p=0.34), aggressive PTC histology (OR 0.55, p=0.15), and age at diagnosis (OR 0.90, p=0.32) were not significant risk factors for a worse initial therapy response. When evaluating the combination of mETE, tumor size, and aggressive PTC histology, the presence of mETE with a >2 cm tumor was significantly associated with a worse outcome (OR 5.27, 95% CI, p=0.014). The role of radioiodine ablation in patients with mETE was also evaluated. When considering radioiodine treatment, propensity score-based matching was performed, and no significant differences were found between treated and non-treated patients (p=0.24). Conclusions: This study failed to show the prognostic value of mETE in predicting initial therapy response in a large cohort of PTC patients without lymph node metastases. The study suggests that the combination of tumor diameter and mETE can be used as a reliable prognostic factor for persistence and could be easily applied in clinical practice to manage PTC patients with low-to-intermediate risk of recurrent/persistent disease

    Determinants of frontline tyrosine kinase inhibitor choice for patients with chronic-phase chronic myeloid leukemia: A study from the Registro Italiano LMC and Campus CML

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    Background: Imatinib, dasatinib, and nilotinib are tyrosine kinase inhibitors (TKIs) approved in Italy for frontline treatment of chronic-phase chronic myeloid leukemia (CP-CML). The choice of TKI is based on a combined evaluation of the patient's and the disease characteristics. The aim of this study was to analyze the use of frontline TKI therapy in an unselected cohort of Italian patients with CP-CML to correlate the choice with the patient's features. Methods: A total of 1967 patients with CP-CML diagnosed between 2012 and 2019 at 36 centers throughout Italy were retrospectively evaluated; 1089 patients (55.4%) received imatinib and 878 patients (44.6%) received a second-generation (2G) TKI. Results: Second-generation TKIs were chosen for most patients aged <45 years (69.2%), whereas imatinib was used in 76.7% of patients aged >65 years (p < .001). There was a predominant use of imatinib in intermediate/high European long-term survival risk patients (60.0%/66.0% vs. 49.7% in low-risk patients) and a limited use of 2G-TKIs in patients with comorbidities such as hypertension, diabetes, chronic obstructive pulmonary disease, previous neoplasms, ischemic heart disease, or stroke and in those with >3 concomitant drugs. We observed a greater use of imatinib (61.1%) in patients diagnosed in 2018-2019 compared to 2012-2017 (53.2%; p = .002). In multivariable analysis, factors correlated with imatinib use were age > 65 years, spleen size, the presence of comorbidities, and ≄3 concomitant medications. Conclusions: This observational study of almost 2000 cases of CML shows that imatinib is the frontline drug of choice in 55% of Italian patients with CP-CML, with 2G-TKIs prevalently used in younger patients and in those with no concomitant clinical conditions. Introduction of the generic formulation in 2018 seems to have fostered imatinib use
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