Cooperation in centralised CATI Household Panel Surveys : A Contact-based Multilevel Analysis to Examine Interviewer, Respondent, and Fieldwork Process Effects

In this research, we analyse the contact-specific mean of the final cooperation probability, distinguishing on the one hand between contacts with household reference persons and with other eligible household members, and on the other hand between first and later contacts. Data comes from two Swiss Household Panel surveys. The interviewer-specific variance is higher for first contacts, especially in the case of the reference person. For later contacts with the reference person, the contact-specific variance dominates. This means that interaction effects and situational factors are decisive. The contact number has negative effects on the performance of contacts with the reference person, positive in the case of other persons. Also time elapsed since the previous contact has negative effects in the case of reference persons. The result of the previous contact has strong effects, especially in the case of the reference person. These findings call for a quick completion of the household grid questionnaire, assigning the best interviewers to conducting the first contact. While obtaining refusals has negative effects, obtaining other contact results has only weak effects on the interviewer's subsequent contact outcome. Using the same interviewer for contacts has no positive effects.

Properties of ideal composite knots.

The shortest tube of constant diameter that can form a given knot represents the 'ideal' form of the knot. Ideal knots provide an irreducible representation of the knot, and they have some intriguing mathematical and physical features, including a direct correspondence with the time-averaged shapes of knotted DNA molecules in solution. Here we describe the properties of ideal forms of composite knots-knots obtained by the sequential tying of two or more independent knots (called factor knots) on the same string. We find that the writhe (related to the handedness of crossing points) of composite knots is the sum of that of the ideal forms of the factor knots. By comparing ideal composite knots with simulated configurations of knotted, thermally fluctuating DNA, we conclude that the additivity of writhe applies also to randomly distorted configurations of composite knots and their corresponding factor knots. We show that composite knots with several factor knots may possess distinct structural isomers that can be interconverted only by loosening the knot.

Explaining Fiscal Balances with a Simultaneous Equation Model of Revenue and Expenditure : A Case Study of Swiss Cantons Using Panel Data

Empirical literature on the analysis of the efficiency of measures for reducing persistent government deficits has mainly focused on the direct explanation of deficit. By contrast, this paper aims at modeling government revenue and expenditure within a simultaneous framework and deriving the fiscal balance (surplus or deficit) equation as the difference between the two variables. This setting enables one to not only judge how relevant the explanatory variables are in explaining the fiscal balance but also understand their impact on revenue and/or expenditure. Our empirical results, obtained by using a panel data set on Swiss Cantons for the period 1980-2002, confirm the relevance of the approach followed here, by providing unambiguous evidence of a simultaneous relationship between revenue and expenditure. They also reveal strong dynamic components in revenue, expenditure, and fiscal balance. Among the significant determinants of public fiscal balance we not only find the usual business cycle elements, but also and more importantly institutional factors such as the number of administrative units, and the ease with which people can resort to political (direct democracy) instruments, such as public initiatives and referendum.

When do we dare to stop biological or immunomodulatory therapy for Crohn's disease? Results of a multidisciplinary European expert panel.

BACKGROUND: Safety and economic issues have increasingly raised concerns about the long term use of immunomodulators or biologics as maintenance therapies for Crohn's disease (CD). Despite emerging evidence suggesting that stopping therapy might be an option for low risk patients, criteria identifying target groups for this strategy are missing, and there is a lack of recommendations regarding this question. METHODS: Multidisciplinary European expert panel (EPACT-II Update) rated the appropriateness of stopping therapy in CD patients in remission. We used the RAND/UCLA Appropriateness Method, and included the following variables: presence of clinical and/or endoscopic remission, CRP level, fecal calprotectin level, prior surgery for CD, and duration of remission (1, 2 or 4 years). RESULTS: Before considering withdrawing therapy, the prerequisites of a C-reactive protein (CRP) and fecal calprotectin measurement were rated as "appropriate" by the panellists, whereas a radiological evaluation was considered as being of "uncertain" appropriateness. Ileo-colonoscopy was considered appropriate 1 year after surgery or after 4 years in the absence of prior surgery. Stopping azathioprine, 6-mercaptopurine or methotrexate mono-therapy was judged appropriate after 4 years of clinical remission. Withdrawing anti-TNF mono-therapy was judged appropriate after 2 years in case of clinical and endoscopic remission, and after 4 years of clinical remission. In case of combined therapy, anti-TNF withdrawal, while continuing the immunomodulator, was considered appropriate after two years of clinical remission. CONCLUSION: A multidisciplinary European expert panel proposed for the first time treatment stopping rules for patients in clinical and/or endoscopic remission, with normal CRP and fecal calprotectin levels.

Antiretroviral treatment of adult HIV infection: 2010 recommendations of the International AIDS Society-USA panel.

CONTEXT: Recent data regarding the consequences of untreated human immunodeficiency virus (HIV) infection and the expansion of treatment choices for antiretroviral-naive and antiretroviral-experienced patients warrant an update of the International AIDS Society-USA guidelines for the use of antiretroviral therapy in adults with HIV infection. OBJECTIVES: To provide updated recommendations for management of HIV-infected adults, using antiretroviral drugs and laboratory monitoring tools available in the international, developed-world setting. This report provides guidelines for when to initiate antiretroviral therapy, selection of appropriate initial regimens, patient monitoring, when to change therapy, and what regimens to use when changing. DATA SOURCES AND STUDY SELECTION: A panel with expertise in HIV research and clinical care reviewed relevant data published or presented at selected scientific conferences since the last panel report through April 2010. Data were identified through a PubMed search, review of scientific conference abstracts, and requests to antiretroviral drug manufacturers for updated clinical trials and adverse event data. DATA EXTRACTION AND SYNTHESIS: New evidence was reviewed by the panel. Recommendations were drafted by section writing committees and reviewed and edited by the entire panel. The quality and strength of the evidence were rated and recommendations were made by full panel consensus. CONCLUSIONS: Patient readiness for treatment should be confirmed before initiation of antiretroviral treatment. Therapy is recommended for asymptomatic patients with a CD4 cell count < or = 500/microL, for all symptomatic patients, and those with specific conditions and comorbidities. Therapy should be considered for asymptomatic patients with CD4 cell count > 500/microL. Components of the initial and subsequent regimens must be individualized, particularly in the context of concurrent conditions. Patients receiving antiretroviral treatment should be monitored regularly; treatment failure should be detected and managed early, with the goal of therapy, even in heavily pretreated patients, being HIV-1 RNA suppression below commercially available assay quantification limits.

A Note on improving Contact Times in Panel Surveys

With increasing costs for conducting surveys, many survey agencies resort to implementing call strategies. Obtaining contact in panel surveys as early as possible, without annoying people by contacting them at undesired times and ultimately causing them to refuse, requires using efficient call time strategies. In this research, the author uses call data from the Swiss Household Panel (SHP), a centralized Computer Assisted Telephone Interview (CATI) survey with a randomized (experimental) call-household assignment. Using random effects models, the author analyzes the efficiency gains of obtaining initial contact by assigning optimal times to first calls, and times and spacing to second and later calls depending on household sociodemography and prior call patterns. The author concludes with some recommendations for making early and successful contact during fieldwork.

Use of Hy's law and a new composite algorithm to predict acute liver failure in patients with drug-induced liver injury.

BACKGROUND & AIMS Hy's Law, which states that hepatocellular drug-induced liver injury (DILI) with jaundice indicates a serious reaction, is used widely to determine risk for acute liver failure (ALF). We aimed to optimize the definition of Hy's Law and to develop a model for predicting ALF in patients with DILI. METHODS We collected data from 771 patients with DILI (805 episodes) from the Spanish DILI registry, from April 1994 through August 2012. We analyzed data collected at DILI recognition and at the time of peak levels of alanine aminotransferase (ALT) and total bilirubin (TBL). RESULTS Of the 771 patients with DILI, 32 developed ALF. Hepatocellular injury, female sex, high levels of TBL, and a high ratio of aspartate aminotransferase (AST):ALT were independent risk factors for ALF. We compared 3 ways to use Hy's Law to predict which patients would develop ALF; all included TBL greater than 2-fold the upper limit of normal (×ULN) and either ALT level greater than 3 × ULN, a ratio (R) value (ALT × ULN/alkaline phosphatase × ULN) of 5 or greater, or a new ratio (nR) value (ALT or AST, whichever produced the highest ×ULN/ alkaline phosphatase × ULN value) of 5 or greater. At recognition of DILI, the R- and nR-based models identified patients who developed ALF with 67% and 63% specificity, respectively, whereas use of only ALT level identified them with 44% specificity. However, the level of ALT and the nR model each identified patients who developed ALF with 90% sensitivity, whereas the R criteria identified them with 83% sensitivity. An equal number of patients who did and did not develop ALF had alkaline phosphatase levels greater than 2 × ULN. An algorithm based on AST level greater than 17.3 × ULN, TBL greater than 6.6 × ULN, and AST:ALT greater than 1.5 identified patients who developed ALF with 82% specificity and 80% sensitivity. CONCLUSIONS When applied at DILI recognition, the nR criteria for Hy's Law provides the best balance of sensitivity and specificity whereas our new composite algorithm provides additional specificity in predicting the ultimate development of ALF.

Appropriate therapy for fistulizing and fibrostenotic Crohn's disease: results of a multidisciplinary expert panel - EPACT II

Introduction: Many therapeutic decisions in the management of fistulizing and fibrostenotic Crohn's disease (CD) have to be taken without the benefit of strong scientific evidence. For this reason, explicit appropriateness criteria for CD fistula and stenosis treatment were developed by a multidisciplinary European expert panel in 2004 with the aim of making them easily available on the Internet and thus allowing individual case scenario evaluation; these criteria were updated in 2007. Methods: Twelve international experts convened in Geneva, Switzerland in December 2007. Explicit clinical scenarios, corresponding to real daily practice, were rated on a 9-point scale based on evidence from the published literature and panelists' own expertise. Median ratings were stratified into three categories: appropriate (7-9), uncertain (4-6) and inappropriate (1-3). Results: Overall, panelists rated 60 indications pertaining to fistulas. Antibiotics, azathioprine/6-mercaptopurine and conservative surgery are the mainstay of therapy for simple and complex fistulas. In the event of previous failure of azathioprine/6-mercaptopurine therapy, methotrexate and infliximab were considered appropriate for complex fistulas. The panel also rated 72 indications related to the management of fibrostenotic CD. The experts considered balloon dilation, if the stricture was endoscopically accessible, stricturoplasty and bowel resection to be appropriate for small bowel fibrostenotic Crohn's disease, and balloon dilation and bowel resection appropriate for fibrostenotic colonic disease. In the presence of an ileocolonic or ileorectal anastomotic stricture of <7 cm, endoscopic balloon dilation, and bowel resection were considered appropriate. Conclusion: Antibiotics, azathioprine/6-mercaptopurine, and conservative surgery are the mainstay of therapy for fistulizing Crohn's disease. Infliximab is a therapeutic option in patients without prior response to immunosuppressant therapy. In fibrostenotic Crohn's disease, endoscopic balloon dilation, if feasible, or surgical therapy should be considered. These expert recommendations are available online (www.epact.ch). Prospective evaluation is now needed to test the validity of these appropriateness criteria in clinical practice. (C) 2009 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.

Attrition in the Swiss Household Panel: Is change associated with drop-out?

This study examines the importance of change in characteristics and circumstances ofhouseholds and household members for contact and cooperation patterns. The literaturesuggests that there might be an underrepresentation of change in panel studies, becauserespondents facing more changes would be more likely to drop out. We approach this problemby analysing whether previous changes are predictive of later attrition or temporary drop-out,using eleven waves of the Swiss Household Panel (1999-2009). Our analyses supportprevious findings to some extent. Changes in household composition, employment status andsocial involvement as well as moving are associated mainly with attrition and less withtemporary drop-out. These changes affect obtaining cooperation rather than obtaining contact,and tend to increase attrition.

The appropriateness of renal angioplasty: the ANPARIA software: a multidisciplinary expert panel approach

Percutaneous transluminal renal angioplasty (PTRA) is an invasive technique that is costly and involves the risk of complications and renal failure. The ability of PTRA to reduce the administration of antihypertensive drugs has been demonstrated. A potentially greater benefit, which nevertheless remains to be proven, is the deferral of the need for chronic dialysis. The aim of the study (ANPARIA) was to assess the appropriateness of PTRA to impact on the evolution of renal function. A standardized expert panel method was used to assess the appropriateness of medical treatment alone or medical treatment with revascularization in various clinical situations. The choice of revascularization by either PTRA or surgery was examined for each clinical situation. Analysis was based on a detailed literature review and on systematically elicited expert opinion, which were obtained during a two-round modified Delphi process. The study provides detailed responses on the appropriateness of PTRA for 1848 distinct clinical scenarios. Depending on the major clinical presentation, appropriateness of revascularization varied from 32% to 75% for individual scenarios (overal 48%). Uncertainty as to revascularization was 41% overall. When revascularization was appropriate, PTRA was favored over surgery in 94% of the scenarios, except in certain cases of aortic atheroma where sugery was the preferred choice. Kidney size [7 cm, absence of coexisting disease, acute renal failure, a high degree of stenosis (C70%), and absence of multiple arteries were identified as predictive variables of favorable appropriateness ratings. Situations such as cardiac failure with pulmonary edema or acute thrombosis of the renal artery were defined as indications for PTRA. This study identified clinical situations in which PTRA or surgery are appropriate for renal artery disease. We built a decision tree which can be used via Internet: the ANPARIA software (http://www.chu-clermontferrand.fr/anparia/). In numerous clinical situations uncertainty remains as to whether PTRA prevents deterioration of renal function.

Appropriateness of therapy for active Crohn's disease: results of a multidisciplinary international Expert Panel (EPACT II)

INTRODUCTION: The development of novel therapies and the increasing number of trials testing management strategies for luminal Crohn's disease (CD) have not filled all the gaps in our knowledge. Thus, in clinical practice, many decisions for CD patients need to be taken without high quality evidence. For this reason, a multidisciplinary European expert panel followed the RAND method to develop explicit criteria for the management of individual patients with active, steroid-dependent (ST-D) and steroid-refractory (ST-R) CD. AIMS & METHODS: Twelve international experts convened in Geneva, Switzerland in December 2007, to rate explicit clinical scenarios, corresponding to real daily practice, on a 9-point scale according to the literature evidence and their own expertise. Median ratings were stratified into three categories: appropriate (7-9), uncertain (4-6) and inappropriate (1-3). RESULTS: Overall, panelists rated 296 indications pertaining to mild-to-moderate, severe, ST-D, and ST-R CD. In anti-TNF naïve patients, budesonide and prednisone were found appropriate for mild-moderate CD, and infliximab (IFX) when those had previously failed or had not been tolerated. In patients with prior success with IFX, this drug with or without co-administration of a thiopurine analog was favored. Other anti-TNFs were appropriate in case of intolerance or resistance to IFX. High doses steroids, IFX or adalimumab were appropriate in severe active CD. Among 105 indications for ST-D or ST-R disease, the panel considered appropriate the thiopurine analogs, methotrexate, IFX, adalimumab and surgery for limited resection, depending on the outcome of prior therapies. Anti-TNFs were generally considered appropriate in ST-R. CONCLUSION: Steroids, including budesonide for mild-to-moderate CD, remain first-line therapies in active luminal CD. Anti-TNFs, in particular IFX with respect to the amount of available evidence, remain second-line for most indications. Thiopurine analogs are preferred to anti-TNFs when steroids are not appropriate, except when anti-TNFs were previously successful. These recommendations are available online (www.epact.ch). A prospective evaluation of these criteria in a large database in Switzerland in underway to validate these criteria.

Appropriate therapy for fistulizing and fibrostenotic Crohn's disease: results of a multidisciplinary international expert panel (EPACT II)

Introduction Many therapeutic decisions in the management of fistulizing and fibrostenotic Crohn's disease (CD) have to be taken without the benefit of strong scientific evidence. For this reason, explicit appropriateness criteria for CD fistula and stenosis treatment were developed by a multidisciplinary European expert panel in 2004 with the aim of making them easily available on the Internet and thus allowing individual case scenario evaluation; these criteria were updated in 2007. Methods Twelve international experts convened in Geneva, Switzerland in December 2007. Explicit clinical scenarios, corresponding to real daily practice, were rated on a 9-point scale based on evidence from the published literature and panelists' own expertise. Median ratings were stratified into three categories: appropriate (7-9), uncertain (4-6) and inappropriate (1-3). Results Overall, panelists rated 60 indications pertaining to fistulas. Antibiotics, azathioprine/6-mercaptopurine and conservative surgery are the mainstay of therapy for simple and complex fistulas. In the event of previous failure of azathioprine/6-mercaptopurine therapy, methotrexate and infliximab were considered appropriate for complex fistulas. The panel also rated 72 indications related to the management of fibrostenotic CD. The experts considered balloon dilation, if the stricture was endoscopically accessible, stricturoplasty and bowel resection to be appropriate for small bowel fibrostenotic Crohn's disease, and balloon dilation and bowel resection appropriate for fibrostenotic colonic disease. In the presence of an ileocolonic or ileorectal anastomotic stricture of <7 cm, endoscopic balloon dilation, and bowel resection were considered appropriate. Conclusion Antibiotics, azathioprine/6-mercaptopurine, and conservative surgery are the mainstay of therapy for fistulizing Crohn's disease. Infliximab is a therapeutic option in patients without prior response to immunosuppressant therapy. In fibrostenotic Crohn's disease, endoscopic balloon dilation, if feasible, or surgical therapy should be considered. These expert recommendations are available online (www.epact.ch). Prospective evaluation is now needed to test the validity of these appropriateness criteria in clinical practice.

How Answers on Political Attitudes are Shaped by Interviewers: Evidence from a Panel Survey

We analyze whether the interviewers' political opinions have an influence on those of the respondents. The research uses data from a panel survey in which interviewers are randomly assigned to respondents. The results show that the respondents express significantly similar opinions to those of the interviewers in all questions considered. Multilevel models show that more educated respondents are affected to a slightly higher extent and that the interviewer's experience is also a factor. There is no difference between different respondent subgroups or when both interviewers and respondents share the same socio-demographic characteristics. While there is no evidence for respondents wanting to please the interviewers, the hypothesis of socially desirable behavior can indeed be confirmed.