Multi-level Modelling of International Variations and Time Trends in Asthma and Allergic Diseases in Children and Adults

Lead Research Organisation: London School of Hygiene & Tropical Medicine
Department Name: Epidemiology and Population Health

Abstract

This project will combine substantive research into asthma causes and time trends with developing statistical methodologies to handle complex multi-level datasets.

The main data sources are from three linked studies:

Phase I (1992-1995) of the International Study of Asthma and Allergies in Childhood (ISAAC) collected information by questionnaire on symptoms and risk factors for asthma, rhinoconjunctivitis and eczema from 721,602 children in 155 collaborating centres in 56 countries.

Phase III (2001-2002) of ISAAC collected similar information from 1,187,496 children in 237 centres in 98 countries.

The Global Asthma Network (GAN) will use the ISAAC methodology to collect similar data during 2016-2017 but with the extension of data on parents and extra questions on asthma management and the environment. To date, 88 centres from 34 countries have registered for GAN and registration is ongoing.

The type of data collected for the studies includes information on symptoms and severity along with environmental and demographic data for three different age groups, one in childhood, one teenage and one adult. This fits in well with the MRC strategic research aims of investigating health through the life course, and understanding how lifestyles and environment affect health. Within each country at least one urban and one rural centre will be sought so the influence of the general environment on asthma can be explored. A sample size of at least 3,000 people per age group per centre will be used to give sufficient power to detect differences in the severity of asthma. In smaller island populations, all pupils in the age group and their parents will be selected.

Starting with the existing ISAAC surveys, which have yet to be fully exploited with state-of-the-art statistical modelling techniques, and later combining it with the GAN survey data it will be possible to run integrated analysis on all three studies. This complex multi-level structure will contain multiple exposures on 3 age groups, at 4 different levels (person, school, centre and country) across up to 3 time points. For some centres there will be missing age groups and/or missing time points which will need to be addressed correctly to ensure the statistical inference is robust.

This aligns well with the MRC skills priorities of quantitative and interdisciplinary skills by combining the development of novel statistical methodologies for large, multi-level datasets with their application on epidemiological questions of potential causes or risk factors for asthma and other allergic diseases.

The results of this project should be useful to public health officials within multiple countries. Understanding the important risk factors at different levels improves the ability to positively impact the prevalence and severity of asthma and other allergic diseases through changing health policies. Outcomes will vary widely from country to country and this work will help estimate the impact of potential policy changes.

In addition, the methodological developments will be useful for statisticians working in other areas of health research but with similarly constructed multi-level datasets.

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
MR/N013638/1 01/10/2016 30/09/2025
1784617 Studentship MR/N013638/1 01/10/2016 30/09/2021 Charlotte Rutter
 
Description Outbreak Control: An introduction to careers in public health 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact A workshop for Year 10 school pupils based on a mock outbreak of malaria in London. 30-40 pupils attended each of 8 2hr sessions so far. There is an introduction, including a video, then students go to 5 different stalls, each specializing in a particular area of public health research. They complete an activity at each school to answer a particular question and at the end their answers help control the London outbreak. The different stalls included are Biostatistics, Field Epidemiology, Diagnostics, Vector Control and Epidemic Modelling.
We have received positive feedback from all the schools so far and have already been back for a repeat visit to two of the schools in order to reach more of their students.

At the beginning of the session we ask the students what types of professionals are involved in dealing with an outbreak. We repeat this question at the end and get considerably more answers.

I am part of a group of MRC funded PhD students who designed and run this activity. We have received funding from LSHTM small grants scheme and the MRC flexible fund from our DTP.

In addition to schools we adapted the session to be undertaken on an ad-hoc basis by visitors to the RI Family Day in 2019.
Year(s) Of Engagement Activity 2018,2019,2020