Methodology of the 2013 Survey
All data contained in the Atlas of MS has been collected in a large international study from October 2012 to June 2013. An online questionnaire was drafted in English based on the original questionnaire used in 2008. A long version was circulated to countries that were better placed to provide more detailed data and a shorter version capturing the key information was developed for the remaining countries.
A glossary of terms used in the questionnaire was also prepared to ensure that the questions were understood in the same way by different respondents.
The final version of the questionnaire covered a wide range of issues broken down into the following sections: epidemiology, clinical management, diagnosis, treatment, support available, quality of life, NMO and paediatric MS.
The next step of the process was to identify the most relevant and appropriate person in each country to be invited to act as “country coordinator” to be the focal point for gathering information and data within that country and organizing the completion of the eight sections of the questionnaire.
For those countries with MSIF member societies or corresponding organizations, the country coordinator was either the senior staff member or senior volunteer of the society or the country representative on the MSIF International Medical & Scientific Board. For countries with no MSIF connection, the country coordinators who provided data for the 2008 Atlas of MS were contacted in the first instance. In situations where this approach was not successful, contacts were sought through various sources such as the World Federation of Neurology, the scientific literature and recommendations by colleagues.
The country coordinators were requested to oversee the completion of the questionnaire, making use of all possible sources of information available to them. All respondents were asked to follow the glossary definitions closely, to maintain uniformity and comparability of the information received. Several repeat requests for completion of the questionnaire were sent to the country coordinator in cases where there was a delay in returning the completed questionnaire. In the case of incomplete or internally inconsistent information, the respondents were contacted to provide further information or clarification. Contacts were requested to provide source information for epidemiological data and for some of the clinical services, and where possible these sources were used to verify the data provided.
Eventually, data was gathered from 104 countrie and entered in an electronic database. This includes 12 new countries since 2008. In addition, 20 countries that participated in 2008 but did not provide an update in 2013 are included in the database bringing the total to 124 countries. Population figures were taken from the UN population prospects 2012 (medium growth).
Countries were grouped into the six WHO regions (Africa, the Americas, Eastern Mediterranean, Europe, South- East Asia and Western Pacific) and also into other relevant groupings as seen on the website.
Countries were also grouped by income levels, based on the World Bank income categories as follows: low income (<US$1,035), lower middle income (US$1,036 – 4,085), upper middle income (US$4,086 – 12,615) and high income (>US$ 12,616).
The data was analysed using MS Excel.
Representativeness of data collected
Completed questionnaires were received from 104 of 193 countries.
Data was collected from 41 countries in the European Region (77%), 18 countries in the Region of the Americas (51%), 13 countries in the African Region (26.1%), 17 countries in the Eastern Mediterranean Region (77%), 9 countries in the Western Pacific Region (33%), and 6 countries in the South-East Asia Region (54%).In terms of population covered, the data pertain to 79% of the world population.
The most important limitation of the dataset is that in the majority of countries a single key person was the source of most or all information. Although most respondents had access to numerous official and unofficial sources of information and were able to consult neurologists within the country, the data received should still be considered as reasonably, but not completely, reliable and accurate. In some instances the data are the best estimates by the respondents. In spite of this limitation, the Atlas of MS remains the most comprehensive compilation of MS resources in the world.
Because the sources of information in most countries were the key persons working in the field of MS, the dataset mainly covers countries where there are MS societies, neurologists or other specialists with an interest in MS or neurology. It is therefore likely that the Atlas of MS gives an over positive view of neurological resources in the world, and there are likely to be very limited or no resources in many of the remaining 89 of the countries that did not provide data.
Data from newer areas such as NMO were not available in many countries including USA and Canada. Data on paediatric MS was only available in a minority of countries and when available, data was often incomplete. We hope the Atlas of MS will stimulate new and rigorous data collection in these areas.
The availability of data on incidence was more limited than that on prevalence, and was provided by only 52 of the 104 countries that participated in the survey. Incidence data is important for monitoring changes in rates of MS over time and in specific populations, where it can provide more accurate measures than prevalence.
It is important to carefully consider all possible explanations for trends observed in data over time or place.
The Atlas of MS is not statistically significant enough to prove cause and effect relationships, but gives a snapshot of best available data at a certain point in time.
In particular, data in the Atlas of MS database for 2013, although the most up-to-date at the time of publication, may sometimes be based on unpublished studies or studies completed between 2008 and 2013.
Care should be taken when making direct comparisons between 2008 and 2013 data.
Please check with MSIF’s head of international scientific and medical research before publishing direct comparisons between 2008 and 2013 data from the Atlas of MS.
MSIF would like to thank the Vanneau Trust, Biogen Idec, Genzyme, Novartis, Merck, Synthon and Teva for their generous financial contributions, which have made the 2013 Atlas of MS update possible.