D.2. Household surveys and (mode 4) receipts for exports of services
7.27. If the population of self-employed persons can be clearly established within households, it may be relevant to collect data on the value of the contracts for services provided abroad by those persons. Separately identifying those who travelled abroad to provide their services would be particularly relevant for obtaining a breakdown by mode of supply for self-employed persons. However, the issues identified above on identification of the population and informants, as well as sampling (i.e. relevance of the data source), are even more prominent in this context as the number of self-employed persons exporting their services abroad may be relatively small and difficult to identify through the use of a specialized household survey. A specialized survey could help collect certain information, such as the business travel survey described below.
7.28. To collect information concerning mode 4, compilers should consider adding a specific question in a household survey about the reason for the trip (“business trip”). In combination with the “self-employed” sociodemographic characteristic, that question can be used as a basis. If such a survey is conducted as a telephone sample, compilers should be aware that self-employed persons are difficult to reach and therefore they should also consider using a specific sample of mobile phone numbers or use a web-based survey.