Gintautas Kaminskas May 24, 2010:

No confusion at all There is no shortage of examples of use of the term "questionnaire survey" from English-speaking countries. One example (from http://freespace.virgin.net/julie.barrett/WebPart5/WebPart5.... :

Before describing how the questionnaire survey was carried out, this introductory Chapter provides some background information on questionnaires and their use. The implications of age-related declines in ability for using elderly questionnaire respondents are examined in Chapter 2. The description of the Disability Information Trust questionnaire survey begins with Chapter 3. The summary and conclusions of the questionnaire survey are given in Part 6 of the report.

The term "questionnaire survey" does not have the same meaning as just "questionnaire". A questionnaire might be in a magazine, or on-line. It may not be part of a survey at all, you may just do it for your own interest. Whereas a "questionnaire survey" is an organised event, with the data from it being studied by third parties.

Valters Feists May 24, 2010:

Why "questionnaire survey" might not work. The filling in of response forms (anketavimas) is often just one part of a bigger process, actually called the "survey". Thus, it would not be really convenient to say that "as part of the survey, a questionnaire survey was conducted".

From another source (EU; perhaps written by non-native users of English), it seems that "questionnaire survey" would have to mean the same as "questionnaire" or "survey questionnaire" -- even more confusion!
http://ec.europa.eu/regional_policy/sources/docgener/evaluat...