2. Global Surveillance Project: Prevalence, Severity and Risk Factors

2.1    Overview of study design

The Global Asthma Network is a cross-sectional, multi-centre, multi-country, epidemiological research methodology which follows and expands on the methodology used in ISAAC Phase Three http://isaac.auckland.ac.nz/phases/phasethree/phasethree.html. All ISAAC publications can be found at http://isaac.auckland.ac.nz/publications/publicationsintro.html. The Global Asthma Network concerns itself primarily with asthma. However ISAAC included rhinoconjunctivitis and eczema, and these related NCDs will be part of the surveillance work of the Global Asthma Network. In addition to two age groups of children (13/14 and 6/7), adults of both age groups of children will also be surveyed.

2.1.1    Questionnaires

Written Questionnaires: These will assess the prevalence and severity of asthma, rhinoconjunctivitis and eczema in defined populations and explore management of asthma and environmental factors. The compulsory age group is 13/14 year old adolescents but not all questions are compulsory. The parents/guardians of the adolescents are strongly recommended for inclusion. Also strongly recommended are 6/7 year old children and their parents/guardians. The adolescent group will complete a questionnaire about themselves at school and will then take home Adult questionnaires for their parent/s/guardian/s to complete about their own health. The younger age group will take questionnaires home for parent/guardian completion a) about the health of their child and b) about their own health.

Video Questionnaire: (strongly recommended for the adolescent group). Following completion of the written questionnaire at school, the adolescents will be shown a 6 minute video with non-verbal scenes of asthma symptoms and they will answer a written questionnaire while the video is playing.

2.1.2    Classification of centres

Centres participating in the Global Asthma Network will register with the GAN Global Centre by completing a Registration Document (section 13), indicating which age groups will participate. They will sign a declaration to undertake the protocol (methodology and data coding and entry) according to the manner prescribed in this manual by the Global Asthma Network Steering Group.

2.1.3    Expression of interest

An ‘Expression of Interest’ form has been in circulation since 2012 and a database of centres established (View
A copy of the ‘Expression of Interest’ form is included in this Manual and can be found in section 12. This form can also be completed via this website: Expression of Interest Form

2.2    Global Asthma Network protocol

1a. Adolescents: 13/14 year olds – written questionnaire (compulsory). The compulsory requirement is the study of the adolescents. Each centre will randomly select schools from a defined geographical sampling frame and a sample of 3000 adolescents (recruited from school class registers) will be invited to participate (this number may be reduced if a centre has less than this number but must not be less than 1000 per centre unless the centre, for example, is a whole island nation with less than 1000 adolescents). They will complete the written questionnaire at school (example section 7). Height and weight measurements (strongly recommended) will be taken by the fieldworkers (refer section 20.4) and recorded on the questionnaire preferably after viewing and completing the video questionnaire (see 1b).
Not all questions need to be included. For further details see section 15

1b. Adolescents: Video questionnaire (strongly recommended). This 6 minute nonverbal video questionnaire on asthma symptoms (example section 7) is strongly recommended for the adolescents. The video was developed for ISAAC in response to potential translation problems with written questionnaires, and was designed to overcome the problems inherent in the administration of written questionnaires in different languages. The video questionnaire was validated for ISAAC^1-6. This will be shown to the students following completion of the written questionnaire.

2.   Children: 6/7 year olds – written questionnaire (strongly recommended). Another strongly recommended component for centres is to recruit an additional sample of 3000 6/7 year old children (this number may be reduced if a centre has less than this number but must not be less than 1000 per centre unless the centre is, for example, a whole island nation with less than 1000 children). The children, identified through school class registers, will take a questionnaire home for their parents/guardians to complete about their child (example section 8). The video and its questionnaire will not be administered to this age group. Height and weight measurements (strongly recommended) will be taken by the fieldworker at school and recorded on the questionnaire when the questionnaires are returned to the school (refer section 20.4).
Not all questions need to be included. For further details see section 15

3.   Adults: - written questionnaire (strongly recommended). A questionnaire on asthma, rhinoconjunctivitis and eczema symptoms, management of asthma and environmental factors has been developed for the parents/guardians of both the adolescents and children (ADULT questionnaire). This is a strongly recommended module about parent/guardian health. Both age groups (13/14 and 6/7) will take the questionnaires home for parental/guardian completion and return them to school (example section 9).
Not all questions need to be included. For further details see section 15

2.3    Requirements for centres

1. Registration: Each prospective centre must register with the GAN Global Centre. The registration document is available from this website on the registration page. Each centre has one named Principal Investigator.

2. Funding and Ethics: Each research centre is responsible for obtaining its own funding and ethical approval. Although some centres may have difficulty arranging funding, unfortunately the Global Asthma Network has no central funds to support centres. In regard to obtaining consent from the participants, for the ethical approval process, we advocate the use of passive consent to ensure the response rate is as high as possible⁷.

3. Centre Report: When a Principal Investigator (or collaborator) sends a completed Registration Document to the GAN Global Centre, a blank Centre Report, for the age group(s) to be studied, is generated and sent back from the GAN Global Centre to the centre. Questions on this report will enable a detailed research protocol to be kept by collaborators, showing how the Global Asthma Network protocol was implemented locally (please read the sample Centre Report in section 14). The Centre Report includes a detailed description of the chosen study area. A map of the centre study area, matching the written description, is required. This should be sent to the GAN Global Centre when the Centre Report and data are submitted. Ideally, the map will be a vector or shape file compatible with Geographic Information Software such as ArcGIS (available from http://www.arcgis.com/). If this is not possible, a hand drawn and scanned map drawn on a commercial street map or printout of google maps or similar will be acceptable. If you require further information regarding this format please contact the GAN Global Centre, info@globalasthmanetwork.org.

4. Data Entry and Transfer: Each centre is responsible for coding, entering and forwarding a copy of the data, to the GAN Global Centre (for details on coding and formats for sending data, see Data and Coding Transfer Section, section 19 of this manual). The GAN Global Centre will acknowledge receipt of the data and forward the completed data sets to one of the two data centres – London (Neil Pearce Neil.pearce@lshtm.ac.uk) for most data sets, and Spain (Luis García Marcos lgmarcos@um.es) for Spanish and Portuguese speaking centres.

5. Publications: Each centre may publish its own data without the approval of the Global Asthma Network Steering Group. However, the GAN Global Centre would appreciate a copy of any independent publications being sent for archiving to info@globalasthmanetwork.org. All publications and communications arising from comparisons of more than five international centres require the approval and authorisation of the Global Asthma Network Steering Group.

From the Global Asthma Network Steering Group

“We invite the widest possible participation in the Global Asthma Network which we envisage to be as successful as ISAAC. The commitment and dedication of every single person that participated in ISAAC, contributed to its enormous success. We believe the Global Asthma Network to be a crucial part of the process by which the nature and causes of the global variation and increases in the prevalence of asthma, rhinoconjunctivitis and eczema may be understood. We wish you well for your research”.