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Adaptive survey design refers to using targeted procedures to recruit different sampled cases. This technique strives to reduce bias and variance of survey estimates by trying to recruit a larger and more balanced set of respondents. However, it is not well understood how adaptive design can improve data and survey estimates beyond the well-established post-survey adjustment. This paper reports the results of an experiment that evaluated the additional effect of adaptive design to post-survey adjustments. The experiment was conducted in the Detroit Metro Area Communities Study in 2021. We evaluated the adaptive design in five outcomes: 1) response rates, 2) demographic composition of respondents, 3) bias and variance of key survey estimates, 4) changes in significant results of regression models, and 5) costs. The most significant benefit of the adaptive design was its ability to generate more efficient survey estimates with smaller variances and smaller design effects. [ABSTRACT FROM AUTHOR]

Responsive survey design is a technique aimed at improving the efficiency or quality of surveys by using incoming data from the field to make design changes. The technique was pioneered on large national surveys, but the tools can also be applied on the smaller-scale surveys most commonly used by sociologists. We demonstrate responsive survey design in a small-scale, list-based sample survey of students on the topic of sexual misconduct. We investigate the impact of individual incentive levels and a two-phase responsive design with changes to mode of contact as approaches for limiting the potential of nonresponse bias in data from such surveys. Our analyses demonstrate that a two-phase design introducing telephone and face-to-face reminders to complete the survey can produce stronger change in response rates and characteristics of those who respond than higher incentive levels. These findings offer tools for sociologists designing smaller-scale surveys of special populations or sensitive topics. [ABSTRACT FROM AUTHOR]

To assess the elements necessary to be a successful learning community (ClinCalc) mentor to medical students from the mentee's perspective. Few such studies have utilized the in-depth and richness of detail obtained in qualitative studies. This qualitative study analyzed four focus group discussions lasting 45–90 min conducted at the University of Texas Southwestern Medical School, which has an established LC, in the year 2018. The groups included 14 pre-clerkship and 8 clerkship students. Investigators evaluated transcriptions of the focus group discussions using ATLAS.ti software. Three overarching categories of discussion emerged from the group discussions: (1) Relationship Competence, (2) Teaching Competence, and (3) Ethical and Compassionate Medical Practice Competence. Relationship Competence themes included "walk with me," relationship is most important, and one-on-one. Teaching Competence themes included above and beyond, recognize and address mentor limitations, and safe and enriching environment. Ethical and Compassionate Medical Practice Competence themes included ethical decision making and compassionate care for diverse patient populations. Mentees focused on various aspects of the mentor-mentee relationship as the single most essential competence. Themes mentees discussed as important qualities of a successful mentor may denote qualities to be prioritized in faculty development and mentor recruitment. Future studies could investigate how the LC environment informs former medical students and promotes patient outcomes. [ABSTRACT FROM AUTHOR]

Large-scale, nationally representative surveys serve many vital functions, but these surveys can be long and burdensome for respondents. Cutting survey length can help to reduce respondent burden and may improve data quality but removing items from these surveys is not a trivial matter. We propose a method to empirically assess item importance and associated burden in national surveys and guide this decision-making process using different research products produced from such surveys. This method is demonstrated using the Survey of Doctorate Recipients (SDR), a biennial survey administered to individuals with a science, engineering, and health doctorate. We used three main sources of information on the SDR variables: a bibliography of documents using the SDR data as a measure of item use and importance, SDR data table download statistics from the Scientists and Engineers Statistical Data System as an additional measure of item use, and web timing paradata and break-off rates as a measure of burden. Putting this information together, we identified 35 unused items (17% of the survey) and found that the most burdensome items are highly important. We conclude with general recommendations for those hoping to employ similar methodologies in the future. [ABSTRACT FROM AUTHOR]

Rats repeatedly exposed to high airborne concentrations of ethylene develop eosinophilic rhinitis and mucous cell hyperplasia/hypertrophy (MCH) in nasal respiratory epithelium. Mechanisms underlying these lesions are not well understood to inform occupational exposure guidelines. In this study, we determined (1) the nasal histopathology in rats episodically exposed to ethylene, (2) the ethylene-induced nasal histopathology in similarly exposed mice, and (3) how innate lymphoid cells (ILCs) play a role in ethylene-induced MCH. Animals were exposed to 0 or 10,000 ppm ethylene, 6 h/d, 5 d/wk, for 2 weeks and sacrificed 1 day or 2 weeks postexposure. Others received three 2-week exposure blocks separated by 2-week intervals of no exposure. Episodic exposure was chosen to aid in distinguishing irritant from immune responses. Mucous cell hyperplasia/hypertrophy was induced by ethylene in both species. Rats developed a mild, but transient, eosinophilic rhinitis. Mucous cell hyperplasia/hypertrophy was transient in mice, but persistent in rats. Increases in epithelial mucosubstances after 2 weeks of exposure were only present in ILC-sufficient mice, but not in ILC-deficient mice suggesting that ILCs play a role in MCH and overexpression of genes associated with mucus production/secretion. These findings in animals suggest that inhaled ethylene does not act as a sensitizing agent and will not induce allergen-like nasal airway disease. [ABSTRACT FROM AUTHOR]

Mice exposed to the air pollutant ozone develop eosinophilic rhinitis that is mediated by group 2, GATA-3+, innate lymphoid cells (ILC2s). In the present study, we determined the influx, persistence, and recall of nasal ILC2s and eosinophils in ozone-exposed mice. C57BL/6 (T/B cell sufficient, ILC sufficient), Rag2−/− (T/B cell deficient, ILC sufficient), and Rag2−/−Il2rg−/− (T/B cell deficient, ILC deficient) mice were exposed to 0 or 0.8 ppm ozone for 1 or 9 weekdays and killed 1 or 17 days postexposure. GATA-3+ lymphocytes were sparse in nasal tissue of air-exposed ILC-sufficient mice and absent in ILC-deficient mice. Nine-day, but not 1-day, ozone exposures induced nasal influxes of eosinophils and GATA-3+ lymphocytes in C57BL/6 and Rag2−/− mice but not in Rag2−/−Il2rg−/− mice. Eosinophils waned 17 days postexposure in ILC-sufficient strains of mice. GATA-3+ lymphocytes in C57BL/6 mice also attenuated after exposure but not in ILC-sufficient Rag2−/− mice. Eosinophils, but not GATA-3+ cells, increased rapidly with reexposure in ILC-sufficient mice. Type 2 immune-related messenger RNA expression correlated with cellular responses to ozone. These new findings in mice further elucidate the role of ILC2s in ozone-induced eosinophilic rhinitis and support epidemiologic associations between ozone exposure and eosinophilic inflammation in children. [ABSTRACT FROM AUTHOR]

Researchers are interested in the effectiveness of adaptive and responsive survey designs that monitor and respond to data using tailored or targeted interventions. These designs often require adherence to protocols, which can be difficult when surveys allow in-person interviewers flexibility in managing cases. This article describes examples of interviewer noncompliance and compliance in adaptive design experiments that occurred in two United States decennial census tests. The two studies tested adaptive procedures including having interviewers work prioritized cases and substitute face-to-face attempts with telephone calls. When to perform such procedures was communicated to interviewers via case management systems that necessitated twice-daily transmissions of data. We discuss reasons when noncompliance may occur and ways to improve compliance. [ABSTRACT FROM AUTHOR]

In this article, we investigate the relationship between interviewer travel behavior and field outcomes, such as contact rates, response rates, and contact attempts in two studies, the National Survey of Family Growth and the Health and Retirement Study. Using call record paradata that have been aggregated to interviewer-day levels, we examine two important cost drivers as measures of interviewer travel behavior: the distance that interviewers travel to segments and the number of segments visited on an interviewer-day. We explore several predictors of these measures of travel -- the geographic size of the sampled areas, measures of urbanicity, and other sample and interviewer characteristics. We also explore the relationship between travel and field outcomes, such as the number of contact attempts made and response rates.Wefind that the number of segments that are visited on each interviewer-day has a strong association with field outcomes, but the number of miles travelled does not. These findings suggest that survey organizations should routinely monitor the number of segments that interviewers visit, and that more direct measurement of interviewer travel behavior is needed. [ABSTRACT FROM AUTHOR]

Nonresponse rates have been growing over time leading to concerns about survey data quality. Adaptive designs seek to allocate scarce resources by targeting specific subsets of sampled units for additional effort or a different recruitment protocol. In order to be effective in reducing nonresponse, the identified subsets of the sample need two key features: 1) their probabilities of response can be impacted by changing design features, and 2) once they have responded, this can have an impact on estimates after adjustment. The National Agricultural Statistics Service (NASS) is investigating the use of adaptive design techniques in the Crops Acreage, Production, and Stocks Survey (Crops APS). The Crops APS is a survey of establishments which vary in size and, hence, in their potential impact on estimates. In order to identify subgroups for targeted designs, we conducted a simulation study that used Census of Agriculture (COA) data as proxies for similar survey items. Different patterns of nonresponse were simulated to identify subgroups that may reduce estimated nonresponse bias when their response propensities are changed. [ABSTRACT FROM AUTHOR]

Exposure to elevated levels of ambient ozone in photochemical smog is associated with eosinophilic airway inflammation and nonatopic asthma in children. In the present study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced nonatopic asthma by using lymphoid cell-sufficient C57BL/6 mice, ILC-sufficient Rag2-/- mice (devoid of T and B cells), and ILC-deficient Rag2-/-112rg-/- mice (depleted of all lymphoid cells including ILCs). Mice were exposed to 0 or 0.8 parts per million ozone for 1 day or 9 consecutive weekdays (4 hr/day). A single exposure to ozone caused neutrophilic inflammation, airway epithelial injury, and reparative DNA synthesis in all strains of mice, irrespective of the presence or absence of ILCs. In contrast, 9-day exposures induced eosinophilic inflammation and mucous cell metaplasia only in the lungs of ILC-sufficient mice. Repeated ozone exposures also elicited increased messenger RNA expression of transcripts associated with type 2 immunity and airway mucus production in ILC-sufficient mice. ILC-deficient mice repeatedly exposed to ozone had no pulmonary pathology or increased gene expression related to type 2 immunity. These results suggest a new paradigm for the biologic mechanisms underlying the development of a phenotype of childhood nonatopic asthma that has been linked to ambient ozone exposures. [ABSTRACT FROM AUTHOR]

This study attempted to integrate key assumptions in Respondent-Driven Sampling (RDS) into the Total Survey Error (TSE) perspectives and examine TSE as a new framework for a systematic assessment of RDS errors. Using two publicly available data sets on HIV-at-risk persons, nonresponse error in the RDS recruitment process and measurement error in network size reports were examined. On nonresponse, the ascertained partial nonresponse rate was high, and a substantial proportion of recruitment chains died early. Moreover, nonresponse occurred systematically: recruiters with lower income and higher health risks generated more recruits; and peers of closer relationships were more likely to accept recruitment coupons. This suggests a lack of randomness in the recruitment process, also shown through sizable intra-chain correlation. Self-reported network sizes suggested measurement error, given their wide dispersion and unreasonable reports. This measurement error has further implications for the current RDS estimators, which use network sizes as an adjustment factor on the assumption of a positive relationship between network sizes and selection probabilities in recruitment. The adjustment resulted in nontrivial unequal weighting effects and changed estimates in directions that were difficult to explain and, at times, illogical. Moreover, recruiters' network size played no role in actual recruitment. TSE may serve as a tool for evaluating errors in RDS, which further informs study design decisions and inference approaches. [ABSTRACT FROM AUTHOR]

Mixed-mode surveys need to determine a number of design parameters that may have a strong influence on costs and errors. In a sequential mixed-mode design with web followed by telephone, one of these decisions is when to switch modes. The web mode is relatively inexpensive but produces lower response rates. The telephone mode complements the web mode in that it is relatively expensive but produces higher response rates. Among the potential negative consequences, delaying the switch from web to telephone may lead to lower response rates if the effectiveness of the prenotification contact materials is reduced by longer time lags, or if the additional e-mail reminders to complete the web survey annoy the sampled person. On the positive side, delaying the switch may decrease the costs of the survey. We evaluate these costs and errors by experimentally testing four different timings (1, 2, 3, or 4 weeks) for the mode switch in a web–telephone survey. This experiment was conducted on the fourth wave of a longitudinal study of the mental health of soldiers in the U.S. Army. We find that the different timings of the switch in the range of 1–4 weeks do not produce differences in final response rates or key estimates but longer delays before switching do lead to lower costs. [ABSTRACT FROM AUTHOR]

Ozone is an irritating gas found in photochemical smog. Epidemiological associations have been made between the onset of asthma and childhood exposures to increasing levels of ambient ozone (i.e., air pollutant–induced nonatopic asthma). Individuals, however, vary in their susceptibility to this outdoor air pollutant, which may be due, in part, to their genetic makeup. The present study was designed to test the hypothesis that there are murine strain-dependent differences in pulmonary and nasal pathologic responses to repeated ozone exposures. C57BL/6NTac and BALB/cNTac mice were exposed to 0 or 0.8 ppm ozone, 4 hr/day, for 9 consecutive weekdays. In both strains of mice, ozone induced eosinophilic inflammation and mucous cell metaplasia in the nasal and pulmonary airways. Lungs of ozone-exposed C57BL/6NTac mice, however, had greater eosinophilic inflammation, mucous cell metaplasia, and expression of genes related to type 2 immunity and airway mucus hypersecretion, as compared to similarly exposed BALB/cNTac mice. Ozone-exposed C57BL/6NTac mice also had greater eosinophilic rhinitis but a similar degree of mucous cell metaplasia in nasal epithelium, as ozone-exposed BALB/cNTac mice. These findings suggest that nonatopic individuals may differ in their inflammatory and epithelial responses to repeated ozone exposures that are due, in part, to genetic factors. [ABSTRACT FROM AUTHOR]

Interest in a multimode approach to surveys has grown substantially in recent years, in part due to increased costs of face-to-face (FtF) interviewing and the emergence of the Internet as a survey mode. Yet, there is little systematic evidence of the impact of a multimode approach on survey costs and errors. This article reports the results of an experiment designed to evaluate whether a mixed-mode approach to a large screening survey would produce comparable response rates at a lower cost than an FtF screening effort. The experiment was carried out in the Health and Retirement Study (HRS), an ongoing panel study of Americans over age 50. In 2010, HRS conducted a household screening survey to recruit new sample members to supplement the existing sample. The experiment varied the sequence of modes with which the screening interview was delivered. One treatment offered mail first, followed by FtF interviewing; the other started with FtF and then mail. A control group was offered only FtF interviewing. Results suggest that the mixed-mode options reduced costs without reducing response rates to the screening interview. There is some evidence, however, that the sequence of modes offered may impact the response rate for a follow-up in-depth interview. [ABSTRACT FROM AUTHOR]

In many surveys there is a great deal of uncertainty about assumptions regarding key design parameters. This leads to uncertainty about the cost and error structures of the surveys. Responsive survey designs use indicators of potential survey error to determine when design changes should be made on an ongoing basis during data collection. These changes are meant to minimize total survey error. They are made during the field period as updated estimates of proxy indicators for the various sources of error become available. In this article we illustrate responsive design in a large continuous data collection: the 2006-2010 U.S. National Survey of Family Growth. We describe three paradata-guided interventions designed to improve survey quality: case prioritization, "screener week," and sample balance. Our analyses demonstrate that these interventions systematically alter interviewer behavior, creating beneficial effects on both efficiency and proxy measures of the risk of nonresponse bias, such as variation in subgroup response rates. [ABSTRACT FROM AUTHOR]

Compared to healthy subjects, individuals with allergic airway disease (e.g., asthma, allergic rhinitis) have enhanced inflammatory responses to inhaled ozone. We created a rodent model of ozone-enhanced allergic nasal responses in Brown Norway rats to test the therapeutic effects of the dietary supplement g-tocopherol (γT). Ovalbumin (OVA)-sensitized rats were intranasally challenged with 0% or 0.5% OVA (in saline) on Days 1 and 2, and then exposed to 0 or 1 ppm ozone (eight hours/day) on Days 4 and 5. Rats were also given 0 or 100 mg/kg γT (p.o., in corn oil) on days 2 through 5, beginning twelve hours after the last OVA challenge. On Day 6, nasal tissues were collected for histological evaluation and morphometric analyses of intraepithelial mucosubstances (IM) and eosinophilic inflammation. Nasal septal tissue was microdissected and analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) for mucin glycoprotein 5AC (MUC5AC) expression levels. Histological analysis revealed mild to moderate eosinophil influx in the mucosa lining the nasal airways and maxillary sinus of OVA-challenged rats (eosinophilic rhinosinusitis). Ozone exposure of allergic rats further increased eosinophils in the maxillary sinus (400%), nasolacrimal duct (250%), and proximal midseptum (150%). Storage of intraepithelial mucosubstances (IM) was not significantly affected by OVA challenge in filtered air-exposed rats, but it was increased by ozone in the septum (45%) and maxillary sinus (55%) of allergic compared to control rats. Treatment with γT attenuated the ozone/ OVA-induced synergistic increases in IM and mucosal eosinophils in both nasal and paranasal airways. γ-Tocopherol also blocked OVA and ozone-induced MUC5AC gene expression. Together, these data describe a unique model of ozone enhancement of allergic rhinosinusitis and the novel therapeutic efficacy of a common supplement, γT, to inhibit ozone exacerbation of allergic airway responses. [ABSTRACT FROM AUTHOR]

An inhalation exposure study for particulate matter (PM) investigates links between exposure and observed changes in respiratory function by evaluating the interactions of chemical and physical properties of the PM with physiological mechanisms. Laboratory studies are useful in this regard, but provide limited information because of the difficulty in reproducing real atmospheric PM compositions and processes. To better understand the types of particles to which people are actually exposed in their daily lives, and the human health risks for source-specific PM, a real world assessment of the source-to-receptor pathways for ambient PM is vital. This was accomplished using a unique mobile air research laboratory (AirCARE1) which enables inhalation exposure studies in real-world settings. The overall goal of this study was to determine the effects of concentrated air particulates (CAPs) from 2 different urban atmospheres in Michigan on the lungs of ovalbumin-sensitized rats concurrently challenged with the allergen. Our work demonstrated that short-term (8 hours) exposure to ambient fine particulate matter (aerodynamic diameter ≤ 2.5 μ m; PM2.5) concentrated from 2 different urban atmospheres in Michigan induced distinct allergic responses in the lungs of rats. This paper presents detailed characterization of CAPs and their sources in an effort to define possible associations between the observed health effects and source-specific ambient PM2.5. [ABSTRACT FROM AUTHOR]

Age-related changes in gross and microscopic structure of the nasal cavity may alter local tissue susceptibility as well as the dose of inhaled toxicant delivered to susceptible sites. This article describes a novel method for the use of magnetic resonance imaging, 3-dimensional airway modeling, and morphometric techniques to characterize the distribution and magnitude of ozone-induced nasal injury in infant monkeys. Using this method, we generated age-specific, 3-dimensional, epithelial maps of the nasal airways of infant Rhesus macaques. The principal nasal lesions observed in this primate model of ozone-induced nasal toxicology were neutrophilic rhinitis, along with necrosis and exfoliation of the epithelium lining the anterior maxilloturbinate. These lesions, induced by acute or cyclic (episodic) exposures, were examined by light microscopy, quantified by morphometric techniques, and mapped on 3-dimensional models of the nasal airways. Here, we describe the histopathologic, imaging, and computational biology methods developed to precisely characterize, localize, quantify, and map these nasal lesions. By combining these techniques, the location and severity of the nasal epithelial injury were correlated with epithelial type, nasal airway geometry, and local biochemical and molecular changes on an individual animal basis. These correlations are critical for accurate predictive modeling of exposure-dose-response relationships in the nasal airways, and subsequent extrapolation of nasal findings in animals to humans for determining risk. [ABSTRACT FROM AUTHOR]

The nose is a very complex organ with multiple functions that include not only olfaction, but also the conditioning (e.g., humidifying, warming, and filtering) of inhaled air. The nose is also a “scrubbing tower” that removes inhaled chemicals that may be harmful to the more sensitive tissues in the lower tracheobronchial airways and pulmonary parenchyma. Because the nasal airway may also be a prime target for many inhaled toxicants, it is important to understand the comparative aspects of nasal structure and function among laboratory animals commonly used in inhalation toxicology studies, and how nasal tissues and cells in these mammalian species may respond to inhaled toxicants. The surface epithelium lining the nasal passages is often the first tissue in the nose to be directly injured by inhaled toxicants. Five morphologically and functionally distinct epithelia line the mammalian nasal passages—olfactory, respiratory, squamous, transitional, and lymphoepithelial—and each nasal epithelium may be injured by an inhaled toxicant. Toxicant-induced epithelial lesions in the nasal passages of laboratory animals (and humans) are often site-specific and dependent on the intranasal regional dose of the inhaled chemical and the sensitivity of the nasal epithelial tissue to the specific chemical. In this brief review, we present examples of nonneoplastic epithelial lesions (e.g., cell death, hyperplasia, metaplasia) caused by single or repeated exposure to various inhaled chemical toxicants. In addition, we provide examples of how nasal maps may be used to record the character, magnitude and distribution of toxicant-induced epithelial injury in the nasal airways of laboratory animals. Intranasal mapping of nasal histopathology (or molecular and biochemical alterations to the nasal mucosa) may be used along with innovative dosimetric models to determine dose/response relationships and to understand if site-specific lesions are driven primarily by airflow, by tissue sensitivity, or by another mechanism of toxicity. The present review provides a brief overview of comparative nasal structure, function and toxicologic pathology of the mammalian nasal epithelium and a brief discussion on how data from animal toxicology studies have been used to estimate the risk of inhaled chemicals to human health. [ABSTRACT FROM AUTHOR]

Background: Learning communities (LCs) are intentionally designed groups that are actively engaged in learning with and from each other. While gaining prominence in US medical schools, LCs show significant variability in their characteristics across institutions, creating uncertainty about how best to measure their effects. Objective: The aim of this study is to describe the characteristics of medical school LCs by primary purpose, structures, and processes and lay the groundwork for future outcome studies and benchmarking for best practices. Methods: Medical school LC directors from programs affiliated with the Learning Communities Institute (LCI) were sent an online survey of program demographics and activities, and asked to upload a program description or summary of the LC's purpose, goals, and how it functions. Descriptive statistics were computed for survey responses and a qualitative content analysis was performed on program descriptions by 3 authors to identify and categorize emergent themes. Results: Of 28 medical school LCs surveyed, 96% (27) responded, and 25 (89%) provided program descriptions for qualitative content analysis. All programs reported longitudinal relationships between students and faculty. Most frequently cited objectives were advising or mentoring (100%), professional development (96%), courses (96%), social activities (85%), and wellness (82%). Primary purpose themes were supporting students' professional development, fostering a sense of community, and creating a sense of wholeness. Structures included a community framework, subdivisions into smaller units, and governance by faculty and students. Process themes included longitudinal relationships, integrating faculty roles, and connecting students across class years. Conclusions: Medical school LCs represent a collection of high-impact educational practices characterized by community and small-group structures, relational continuity, and collaborative learning as a means to guide and holistically support students in their learning and development as physicians. In describing 27 medical school LCs, this study proposes a unifying framework to facilitate future educational outcomes studies across institutions. [ABSTRACT FROM AUTHOR]