Mobile phones and telephone survey methods

The methods applied in telephone surveys have been based on the idea that households usually have one fixed landline phone. The popularity of mobile phones has increased very rapidly especially in Western Europe and varies considerably from country to country. This has both indirect and direct effects on telephone survey methods and practice, e.g. survey costs, sampling related issues, nonresponse and estimation. Nevertheless, very few reports refer to the potential impacts that the mobile phones may have in surveys. This paper has two parts: First the structure of telephone coverage in Finland will be described. The change of the structure in Finland has been one of the fastest and the first part serves as an example because it is possible that similar change will take place in other countries as well. The second part deals with the influences mobile phones have had in Finland and what potential impact there may be still ahead.