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Background: High response rates are needed in population-based studies, as nonresponse reduces effective sample size and bias affects accuracy and decreases the generalizability of the study findings., Objective: We tested different strategies to improve response rate and reduce nonresponse bias in a national population-based COVID-19 surveillance program in England, United Kingdom., Methods: Over 19 rounds, a random sample of individuals aged 5 years and older from the general population in England were invited by mail to complete a web-based questionnaire and return a swab for SARS-CoV-2 testing. We carried out several nested randomized controlled experiments to measure the impact on response rates of different interventions, including (1) variations in invitation and reminder letters and SMS text messages and (2) the offer of a conditional monetary incentive to return a swab, reporting absolute changes in response and relative response rate (95% CIs)., Results: Monetary incentives increased the response rate (completed swabs returned as a proportion of the number of individuals invited) across all age groups, sex at birth, and area deprivation with the biggest increase among the lowest responders, namely teenagers and young adults and those living in more deprived areas. With no monetary incentive, the response rate was 3.4% in participants aged 18-22 years, increasing to 8.1% with a £10 (US $12.5) incentive, 11.9% with £20 (US $25.0), and 18.2% with £30 (US $37.5) (relative response rate 2.4 [95% CI 2.0-2.9], 3.5 [95% CI 3.0-4.2], and 5.4 [95% CI 4.4-6.7], respectively). Nonmonetary strategies had a modest, if any, impact on response rate. The largest effect was observed for sending an additional swab reminder (SMS text message or email). For example, those receiving an additional SMS text message were more likely to return a completed swab compared to those receiving the standard email-SMS approach, 73.3% versus 70.2%: percentage difference 3.1% (95% CI 2.2%-4.0%)., Conclusions: Conditional monetary incentives improved response rates to a web-based survey, which required the return of a swab test, particularly for younger age groups. Used in a selective way, incentives may be an effective strategy for improving sample response and representativeness in population-based studies., (©Christina J Atchison, Nicholas Gilby, Galini Pantelidou, Sam Clemens, Kevin Pickering, Marc Chadeau-Hyam, Deborah Ashby, Wendy S Barclay, Graham S Cooke, Ara Darzi, Steven Riley, Christl A Donnelly, Helen Ward, Paul Elliott. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org).)

Introduction: Pregnancy and the first few years of a child's life are important windows of opportunity in which to equalise life chances. A Better Start (ABS) is an area-based intervention being delivered in five areas of socioeconomic disadvantage across England. This protocol describes an evaluation of the impact and cost-effectiveness of ABS., Methods and Analysis: The evaluation of ABS comprises a mixed-methods design including impact, cost-effectiveness and process components. It involves a cohort study in the 5 ABS areas and 15 matched comparison sites (n=2885), beginning in pregnancy in 2017 and ending in 2024 when the child is age 7, with a separate cross-sectional baseline survey in 2016/2017. Process data will include a profiling of the structure and services being provided in the five ABS sites at baseline and yearly thereafter, and data regarding the participating families and the services that they receive. Eligible participants will include pregnant women living within the designated sites, with recruitment beginning at 16 weeks of pregnancy. Data collection will involve interviewer-administered and self-completion surveys at eight time points. Primary outcomes include nutrition, socioemotional development, speech, language and learning. Data analysis will include the use of propensity score techniques to construct matched programme and comparison groups, and a range of statistical techniques to calculate the difference in differences between the intervention and comparison groups. The economic evaluation will involve a within-cohort study economic evaluation to compare individual-level costs and outcomes, and a decision analytic cost-effectiveness model to estimate the expected incremental cost per unit change in primary outcomes for ABS in comparison to usual care., Ethics and Dissemination: Ethical approval to conduct the study has been obtained. The learning and dissemination workstream involves working within and across the sites to generate learning via communities of practice and a range of learning and dissemination events., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Rhinovirus infections cause wheeze, cough, and bronchial hyperresponsiveness. To investigate the involvement of cysteinyl-leukotrienes and prostanoids in these symptoms, bronchial biopsy specimens from 9 normal subjects (nonatopic and with no history of chronic lung disease) were immunostained for 5-lipoxygenase (5-LO) and cyclooxygenase (COX) pathway enzymes 2 weeks before and 4 days after experimental infection with human rhinovirus serotype 16. 5-LO-positive cell counts increased 9-fold (from 0.48 to 4.4 cells/mm(2); P <.05), and 5-LO-activating protein (FLAP)-positive cell counts increased 3.6-fold (from 1.8 to 6.5 cells/mm(2); P =.09). Levels of leukotriene A(4) hydrolase and leukotriene C(4) synthase were unchanged. COX-2--positive cell counts increased from 0 to 2.6 cells/mm(2) (P =.009), with no change in COX-1 levels. Increases of 3-4-fold were seen in levels of macrophages (P =.02) and mast cells (P =.07) but not of eosinophils (P >.4), and bronchoalveolar lavage fluid cysteinyl-leukotriene levels doubled (from 11.2 to 20.4 pg/mL; P =.13). Cold symptom scores correlated with bronchial immunostaining for FLAP (rho = 0.93; P =.001). In normal subjects, rhinovirus colds induce bronchial inflammation with markedly enhanced expression of 5-LO pathway proteins and COX-2.