Understanding the patterns and health impact of indoor air pollutant exposures in Bradford, UK: a study protocol.

INTRODUCTION: Relative to outdoor air pollution, there is little evidence examining the composition and concentrations of indoor air pollution and its associated health impacts. The INGENIOUS project aims to provide the comprehensive understanding of indoor air pollution in UK homes. METHODS AND ANALYSIS: 'Real Home Assessment' is a cross-sectional, multimethod study within INGENIOUS. This study monitors indoor air pollutants over 2 weeks using low-cost sensors placed in three rooms in 300 Born in Bradford (BiB) households. Building audits are completed by researchers, and participants are asked to complete a home survey and a health and behaviour questionnaire, in addition to recording household activities and health symptoms on at least 1 weekday and 1 weekend day. A subsample of 150 households will receive more intensive measurements of volatile organic compound and particulate matter for 3 days. Qualitative interviews conducted with 30 participants will identify key barriers and enablers of effective ventilation practices. Outdoor air pollution is measured in 14 locations across Bradford to explore relationships between indoor and outdoor air quality. Data will be analysed to explore total concentrations of indoor air pollutants, how these vary with building characteristics, and whether they are related to health symptoms. Interviews will be analysed through content and thematic analysis. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the NHS Health Research Authority Yorkshire and the Humber (Bradford Leeds) Research Ethics Committee (22/YH/0288). We will disseminate findings using our websites, social media, publications and conferences. Data will be open access through the BiB, the Open Science Framework and the UK Data Service.

Growing up in Bradford: protocol for the age 7-11 follow up of the Born in Bradford birth cohort.

BACKGROUND: Born in Bradford (BiB) is a prospective multi-ethnic pregnancy and birth cohort study that was established to examine determinants of health and development during childhood and, subsequently, adult life in a deprived multi-ethnic population in the north of England. Between 2007 and 2010, the BiB cohort recruited 12,453 women who experienced 13,776 pregnancies and 13,858 births, along with 3353 of their partners. Forty five percent of the cohort are of Pakistani origin. Now that children are at primary school, the first full follow-up of the cohort is taking place. The aims of the follow-up are to investigate the determinants of children's pre-pubertal health and development, including through understanding parents' health and wellbeing, and to obtain data on exposures in childhood that might influence future health. METHODS: We are employing a multi-method approach across three data collection arms (community-based family visits, school based physical assessment, and whole classroom cognitive, motor function and wellbeing measures) to follow-up over 9000 BiB children aged 7-11 years and their families between 2017 and 2021. We are collecting detailed parent and child questionnaires, cognitive and sensorimotor assessments, blood pressure, anthropometry and blood samples from parents and children. Dual x-ray absorptiometry body scans, accelerometry and urine samples are collected on subsamples. Informed consent is collected for continued routine data linkage to health, social care and education records. A range of engagement activities are being used to raise the profile of BiB and to disseminate findings. DISCUSSION: Our multi-method approach to recruitment and assessment provides an efficient method of collecting rich data on all family members. Data collected will enhance BiB as a resource for the international research community to study the interplay between ethnicity, socioeconomic circumstances and biology in relation to cardiometabolic health, mental health, education, cognitive and sensorimotor development and wellbeing.

Personal assessment of the external exposome during pregnancy and childhood in Europe.

The human exposome affects child development and health later in life, but its personal external levels, variability, and correlations are largely unknown. We characterized the personal external exposome of pregnant women and children in eight European cities. Panel studies included 167 pregnant women and 183 children (aged 6-11 years). A personal exposure monitoring kit composed of smartphone, accelerometer, ultraviolet (UV) dosimeter, and two air pollution monitors were used to monitor physical activity (PA), fine particulate matter (PM2.5), black carbon, traffic-related noise, UV-B radiation, and natural outdoor environments (NOE). 77% of women performed the adult recommendation of ≥150 min/week of moderate to vigorous PA (MVPA), while only 3% of children achieved the childhood recommendation of ≥60 min/day MVPA. 11% of women and 17% of children were exposed to daily PM2.5 levels higher than recommended (≥25µg/m3). Mean exposure to noise ranged from Lden 51.1 dB in Kaunas to Lden 65.2 dB in Barcelona. 4% of women and 23% of children exceeded the recommended maximum of 2 Standard-Erythemal-Dose of UV-B at least once a week. 33% of women and 43% of children never reached the minimum NOE contact recommendation of ≥30 min/week. The variations in air and noise pollution exposure were dominated by between-city variability, while most of the variation observed for NOE contact and PA was between-participants. The correlations between all personal exposures ranged from very low to low (Rho < 0.30). The levels of personal external exposures in both pregnant women and children are above the health recommendations, and there is little correlation between the different exposures. The assessment of the personal external exposome is feasible but sampling requires from one day to more than one year depending on exposure due to high variability between and within cities and participants.

Born in Bradford's Better Start: an experimental birth cohort study to evaluate the impact of early life interventions.

BACKGROUND: Early interventions are recognised as key to improving life chances for children and reducing inequalities in health and well-being, however there is a paucity of high quality research into the effectiveness of interventions to address childhood health and development outcomes. Planning and implementing standalone RCTs for multiple, individual interventions would be slow, cumbersome and expensive. This paper describes the protocol for an innovative experimental birth cohort: Born in Bradford's Better Start (BiBBS) that will simultaneously evaluate the impact of multiple early life interventions using efficient study designs. Better Start Bradford (BSB) has been allocated £49 million from the Big Lottery Fund to implement 22 interventions to improve outcomes for children aged 0-3 in three key areas: social and emotional development; communication and language development; and nutrition and obesity. The interventions will be implemented in three deprived and ethnically diverse inner city areas of Bradford. METHOD: The BiBBS study aims to recruit 5000 babies, their mothers and their mothers' partners over 5 years from January 2016-December 2020. Demographic and socioeconomic information, physical and mental health, lifestyle factors and biological samples will be collected during pregnancy. Parents and children will be linked to their routine health and local authority (including education) data throughout the children's lives. Their participation in BSB interventions will also be tracked. BiBBS will test interventions using the Trials within Cohorts (TwiCs) approach and other quasi-experimental designs where TwiCs are neither feasible nor ethical, to evaluate these early life interventions. The effects of single interventions, and the cumulative effects of stacked (multiple) interventions on health and social outcomes during the critical early years will be measured. DISCUSSION: The focus of the BiBBS cohort is on intervention impact rather than observation. As far as we are aware BiBBS is the world's first such experimental birth cohort study. While some risk factors for adverse health and social outcomes are increasingly well described, the solutions to tackling them remain elusive. The novel design of BiBBS can contribute much needed evidence to inform policy makers and practitioners about effective approaches to improve health and well-being for future generations.

The development of the MeDALL Core Questionnaires for a harmonized follow-up assessment of eleven European birth cohorts on asthma and allergies.

BACKGROUND: Numerous birth cohorts have been initiated in the world over the past 30 years using heterogeneous methods to assess the incidence, course and risk factors of asthma and allergies. The aim of the present work is to provide the stepwise proceedings of the development and current version of the harmonized MeDALL-Core Questionnaire (MeDALL-CQ) used prospectively in 11 European birth cohorts. METHODS: The harmonization of questions was accomplished in 4 steps: (i) collection of variables from 14 birth cohorts, (ii) consensus on questionnaire items, (iii) translation and back-translation of the harmonized English MeDALL-CQ into 8 other languages and (iv) implementation of the harmonized follow-up. RESULTS: Three harmonized MeDALL-CQs (2 for parents of children aged 4-9 and 14-18, 1 for adolescents aged 14-18) were developed and used for a harmonized follow-up assessment of 11 European birth cohorts on asthma and allergies with over 13,000 children. CONCLUSIONS: The harmonized MeDALL follow-up produced more comparable data across different cohorts and countries in Europe and will offer the possibility to verify results of former cohort analyses. Thus, MeDALL can become the starting point to stringently plan, conduct and support future common asthma and allergy research initiatives in Europe.

What factors explain pregnant women's feeding intentions in Bradford, England: a multi-methods, multi-ethnic study.

BACKGROUND: Using a multi-methods approach we aimed to explore the relative prediction of demographic, socioeconomic and modifiable predictors from the Theory of Planned behaviour (TPB) in explaining feeding intentions amongst a multi-ethnic sample. METHODS: 476 women completed a questionnaire at 28 weeks gestation. They were grouped into breastfeeding (N = 258), mixed-feeding (N = 50), bottle-feeding (N = 88) intenders, or a no clear intention (N = 88). Multinomial adjusted regressions explored the influence of modifiable TPB factors, along with ethnicity and socioeconomic status in predicting group membership. Free-text responses allowed women to elaborate on reasons behind their intention. RESULTS: TPB factors were significant predictors of feeding intention. Women with high intention to breastfeed were less likely to report high attitudes in any other feeding alternative. Bottle-feeding intenders reported poorer self-efficacy regarding breastfeeding compared to breastfeeding intenders (prevalence rate ratio, PRR = 0.10). Mixed and bottle-feeding intenders reported greater self-efficacy for mixed-feeding (PRR = 1.80, 5.50 respectively). Descriptive norms for mixed (PRR = 13.77) and bottle-feeding (PRR = 10.68) were predictive of mixed-feeding intention. Reasons for breastfeeding intentions related to health considerations, whilst bottle-feeding reasons related to convenience. Mixed-feeding intenders reported both breast and bottle-related factors. CONCLUSIONS: Understanding modifiable predictors related to feeding intentions like TPB factors can help professionals target appropriate interventions to encourage breastfeeding.

Ethnic differences in the initiation and duration of breast feeding--results from the born in Bradford Birth Cohort Study.

BACKGROUND: Initiation of breast feeding and duration of any breast feeding are known to differ by ethnic group, but there are limited data on differences in exclusive breast feeding. This study aimed to determine if there are ethnic differences in the initiation and duration of any and exclusive breast feeding. METHODS: Breast-feeding data were obtained from a subsample of 1365 women recruited to a multi-ethnic cohort study (Born in Bradford) between August 2008 and March 2009. Poisson regression was used to investigate the impact of socio-economic, life style and birth factors on ethnic differences in the prevalence of breast feeding. RESULTS: Compared with white British mothers, initiation of breast feeding was significantly higher in all ethnic groups and this persisted after adjustment for socio-economic, life style and birth factors [Pakistani: prevalence rate ratio (PRR) = 1.19 (95% confidence interval 1.10, 1.29); Other South Asian: PRR = 1.29 (1.18, 1.42); Other ethnicities: PRR = 1.33 (1.21, 1.46)]. There were no differences in exclusive breast feeding at 4 months [Pakistani: PRR = 0.77 (0.54, 1.09); Other South Asian: PRR = 1.55 (0.99, 2.43); Other ethnicities: PRR = 1.50 (0.88, 2.56)]. Any breast feeding at 4 months was significantly higher in mothers of all non-white British ethnicities [Pakistani: PRR = 1.27 (1.02, 1.58); Other South Asian: PRR = 1.99 (1.52, 2.62); Other ethnicities: 2.45 (1.86, 3.21)]. CONCLUSIONS: Whilst women of ethnic minority groups were significantly more likely to initiate breast feeding and continue any breast feeding for 4 months compared with white British women, the rates of exclusive breast feeding at 4 months were not significantly different once socio-economic, life style and birth factors were accounted for.