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11.4. To assess the advantages and disadvantages of different sources with respect to their coverage of the specific service category, some collection practices are marked with a double plus sign (++) in order to illustrate that they, relatively, present the most advantages. However, the reader should always be aware that, depending on national circumstances, the suggested source might not always be the best option for every country and that, in practice, other sources or a combination of sources can be more suitable for collecting the necessary information.
Next: B. Comparison of data sources for resident/non-resident transactions