The wave 6 NEPS adult study incentive experiment

"In wave 6 of the National Educational Panel Study (NEPS) adult starting cohort, an incentive experiment was conducted that randomly switched respondent cash incentives from promised to (partly) prepaid for half of the eligible sample. This research note examines the effects that this change in incentive scheme had on response rates, on sample composition in terms of some key survey variables, and fieldwork efforts by interviewers. We find moderately sized positive effects on overall response rates. The switch in incentive scheme appears to be particularly effective in raising response rates of low educated individuals and those with low reading and mathematics competencies, subgroups that participated underproportionately in prior waves. This differential reaction to the changed incentive scheme therefore leads to a somewhat more balanced sample composition along these dimensions. In line with prior studies, effects on fieldwork efforts such as the number of contact attempts to obtain an interview could be found, but are small in magnitude." (author's abstract

Design and stratification of PASS : a new panel study for research on long term unemployment

"The paper introduces the general design features and particularities of a new largescale panel study for research on recipients of benefits for the long-term unemployed (the so called Unemployment Benefit II) in Germany that combines a sample of 6000 recipient households with an equally large sample of the general population. Particular focus is on the sampling procedure for the general population, where a commercial database was used to draw a sample stratified by status." (Author's abstract, IAB-Doku) ((en))IAB-Haushaltspanel - Konzeption, empirische Sozialforschung, Erhebungsmethode, Stichprobe, Langzeitarbeitslosigkeit

Wechsel des Erhebungsinstituts und Adressweitergabe mit Widerspruchsverfahren im IAB-Haushaltspanel PASS: ein Praxisbericht

"Wechsel des Erhebungsinstituts zwischen den Erhebungswellen einer wissenschaftlichen Panelstudie sind selten. Die möglichen Effekte eines solchen Institutswechsels sind im Vorhinein schwer abzuschätzen und methodisch kaum untersucht. Zudem erschweren in der Praxis datenschutzrechtliche Anforderungen einen Institutswechsel. So wurde, wie bei den meisten akademischen Studien in der Bundesrepublik üblich, auch den in PASS (Panel 'Arbeitsmarkt und Soziale Sicherung') zu befragenden Haushalten in einem vorab versandten Merkblatt zum Datenschutz zugesagt, dass Name und Anschrift der Befragten nicht an Dritte weitergegeben werden. Um nicht gegen diese Zusage zu verstoßen, war es geboten, alle teilnehmenden Haushalte über den anstehenden Institutswechsel zu informieren und diesen eine explizite, für sie kostenlose, Widerspruchsmöglichkeit gegen die Weitergabe ihrer Daten an das neue Erhebungsinstitut einzuräumen. Diesbezüglich werden im Folgenden Vorgehensweise und Erfahrungen beschrieben, die unter Umständen auch für andere Panelstudien bei zukünftigen Institutswechseln von Relevanz sein könnten. Dabei werden insbesondere Ausmaß und Struktur der Panelausfälle durch Widerspruch gegen eine Adressweitergabe näher untersucht." (Autorenreferat)"Ongoing longitudinal surveys seldom switch fieldwork agencies between waves. The possible effects of such a change are difficult to estimate in advance and have, until now, rarely been explored. In addition, data privacy statements hamper the switch between fieldwork agencies in practice. As in most other academic surveys in Germany, the households to be surveyed in PASS (Panel Study 'Labour Market and Social Security') were assured in advance in writing that their name and address data would not be passed on to third parties. To comply with this data privacy statement, the PASS survey needed to inform all the participating households of the upcoming change in fieldwork agency and to give them the opportunity to explicitly object to the transfer of their address data. This article reports the effects of this notification, which may be of relevance for other panel studies in future. Moreover, it attempts to quantify the costs relating to a change of fieldwork agency in terms of magnitude and selectivity of the panel attrition arising in particular from the objection to the transfer of address data." (author's abstract

The fade away of an initial bias in longitudinal surveys

We propose a new view of initial nonresponse bias in longitudinal surveys. Under certain conditions, an initial bias may "fade-away" over consecutive waves. This effect is discussed in a Markovian framework. A general contraction theorem for time inhomogeneous Markov chains is presented. The result is that two chains with different starting distributions will eventually converge to equal state distributions. Two conditions are required: transition probabilities must be equal for respondents and nonrespondents, and attrition in later panel waves must not depend on the state of the individuals. The theory is applied to a German survey on social benefit recipience. Minor deviations from assumptions are shown to have only a negligible impact on the strength of the fade-away effect. Results from other European surveys indicate that the fade-away effect is present in them, as well. Extensions are pointed out

Codebook and documentation of the panel study 'Labour Market and Social Security' (PASS) : vol. 1: Introduction and overview, wave 1 (2006/2007)

"The panel study 'Labour Market and Social Security' (PASS), established by the Institute for Employment Research (IAB), is a new dataset for labour market, welfare state and poverty research in Germany, creating a new empirical basis for the scientific community and political consulting. This Datenreport provides an overview of the first survey wave, for which 18,954 persons were interviewed in 12,794 households between December 2006 and July 2007. The study is carried out as part of the IAB's research into the German Social Code Book II (SGB II). The IAB is charged by law with studying the effects of benefits under SGB II for integration into the labour market and subsistence benefits. However, due to the complex sample design, it also enables researchers to answer questions far beyond these issues. Five core questions influenced the development of the new study, which are detailed in Achatz et al. (2007): 1. What options exist to regain independence from Unemployment Benefit II? 2. In which ways does the social situation of a household change when it receives benefits? 3. How do persons concerned cope with their situation? Will attitudes of the respondents that are constitutive for their actions change over time? 4. In which form do contacts between benefit recipients and institutions providing basic social security actually take place? What are the institutional procedures applied in practice? 5. Which employment career patterns or household dynamics lead to receipt of Unemployment Benefit II? The following brief overview describes the motivation for carrying out the survey, its contents and the study design." (text excerpt, IAB-Doku) ((en)) Additional Information Questionnaires of the first wave. Here you can find the German version. Further information about the panel study "Labour Market and Social Security"IAB-Haushaltspanel, Datengewinnung, Erhebungsmethode, Stichprobe, Panel - Methode, Datenaufbereitung

Comparison of two devices and two breathing patterns for exhaled breath condensate sampling.

Analysis of exhaled breath condensate (EBC) is a noninvasive method to access the epithelial lining fluid of the lungs. Due to standardization problems the method has not entered clinical practice. The aim of the study was to assess the comparability for two commercially available devices in healthy controls. In addition, we assessed different breathing patterns in healthy controls with protein markers to analyze the source of the EBC. EBC was collected from ten subjects using the RTube and ECoScreen Turbo in a randomized crossover design, twice with every device--once in tidal breathing and once in hyperventilation. EBC conductivity, pH, surfactant protein A, Clara cell secretory protein and total protein were assessed. Bland-Altman plots were constructed to display the influence of different devices or breathing patterns and the intra-class correlation coefficient (ICC) was calculated. The volatile organic compound profile was measured using the electronic nose Cyranose 320. For the analysis of these data, the linear discriminant analysis, the Mahalanobis distances and the cross-validation values (CVV) were calculated. Neither the device nor the breathing pattern significantly altered EBC pH or conductivity. ICCs ranged from 0.61 to 0.92 demonstrating moderate to very good agreement. Protein measurements were greatly influenced by breathing pattern, the device used, and the way in which the results were reported. The electronic nose could distinguish between different breathing patterns and devices, resulting in Mahalanobis distances greater than 2 and CVVs ranging from 64% to 87%. EBC pH and (to a lesser extent) EBC conductivity are stable parameters that are not influenced by either the device or the breathing patterns. Protein measurements remain uncertain due to problems of standardization. We conclude that the influence of the breathing maneuver translates into the necessity to keep the volume of ventilated air constant in further studies

Design and stratification of PASS: a new panel study for research on long term unemployment

"Dieses Discussion Paper stellt Design und Besonderheiten der Panelstudie PASS vor. PASS ist im Rahmen der SGB-II-Forschung im IAB angesiedelt und kombiniert eine Zufallsstichprobe von 6.000 Haushalten, die Leistungen nach dem SGB II erhalten, mit einer ebenso großen Stichprobe der allgemeinen Bevölkerung. Dieses Design ermöglicht die Beantwortung einer Vielzahl von Fragestellungen der Arbeitsmarkt-, Armuts- und Sozialstaatsforschung. Im Ergebnisteil analysieren wir die Auswirkungen der Schichtung der Bevölkerungsstichprobe nach dem Statusindex eines kommerziellen Anbieters." (Autorenreferat)"The paper introduces the general design features and particularities of a new largescale panel study for research on recipients of benefits for the long-term unemployed (the so called Unemployment Benefit II) in Germany that combines a sample of 6000 recipient households with an equally large sample of the general population. Particular focus is on the sampling procedure for the general population, where a commercial database was used to draw a sample stratified by status." (author's abstract

New Expression Method and Characterization of Recombinant Human Granulocyte Colony Stimulating Factor in a Stable Protein Formulation

Human recombinant granulocyte colony stimulating factor (rhG-CSF) is widely used in hematology and oncology for the treatment of neutropenia, for the restoration of neutrophil production after bone marrow transplantation, for myelodysplastic syndromes, and aplastic anemia. The E. coli expression system is commonly used for fast recombinant production of rhG-CSF at a large scale. We have applied a novel autoinduction method for the batch expression of rhG-CSF to study whether this new system would increase cell mass and target-protein yield compared to conventional E. coli cell culture and induction with isopropyl ?-D-thiogalactopyranoside (IPTG). We could demonstrate 3-fold higher culture densities and a 5-fold higher protein yield compared to IPTG induction without the need to monitor cell growth in a shortened 24 h expression procedure. rhG-CSF expressed in autoinduction media was successfully extracted from E. coli inclusion bodies and refolded by dialysis. After size exclusion chromatography (SEC) purification, rhG-CSF showed similar conformation, biological activity and aggregation profile compared to the commercially available biosimilar TEVAgrastim® (TEVA Pharma AG). Expression by autoinduction is suggested as a cost- and time-effective method for rhG-CSF production

Codebook and documentation of the panel study 'Labour Market and Social Security' (PASS) : Volume I: Introduction and overview. Wave 2 (2007/2008)

"The panel study 'Labour Market and Social Security' (PASS), established by the Institute for Employment Research (IAB), is a new dataset for labour market, welfare state and poverty research in Germany, creating a new empirical basis for the scientific community and for policy advice. This Datenreport provides an overview of the second survey wave, for which 12,487 individuals were interviewed in 8,429 households between December 2007 and July 2008. 10,114 individuals and 7,342 households were interviewed for the second time in the context of PASS. The spectrum of questions and the design of PASS are intended to close gaps in the existing stock of data. PASS has three main characteristics that extend analysis potential beyond that of the Federal Employment Agency's administrative data: 1. The panel takes the household context into account - including the situation before and after receipt of Unemployment Benefit II. 2. The panel is complete in that it covers all groups of persons and all employment biographies, not only people in dependent employment, unemployed people and those in need of assistance. The dataset also provides information on the status during phases of economic inactivity, self-employment or employment as civil servants. 3. The panel collects additional or significantly more detailed data on relevant characteristics such as attitudes, employment potential or job-search behaviour." (Author's abstract, IAB-Doku) ((en)) Additional Information Questionnaires of the second wave. Here you can find the German version. Further information about the panel study "Labour Market and Social Security".IAB-Haushaltspanel, Datengewinnung, Erhebungsmethode, Stichprobe, Panel - Methode, Datenaufbereitung