Visual Analogue Scales in Cross Cultural Web Surveys
Frederik Funke, Ulf-Dietrich Reips, & Randall K. Thomas
Paper presented at the
7th international conference
RC-33 (Research Comittee 33 "Logic and Methodology")
International Sociological Association (ISA), Neapel (I).
We conducted two Web experiments to examine the quality of data from visual analogue
scales (VAS) and to investigate if the scales are used consistently across different cultural
In the first study, the sample consisted of German students (n = 355). The participants were
asked to repeatedly allocate 13 different percentages on a VAS (the ends were labelled with
0% respectively 100%). We analyzed the precision by comparing target values and actual
values across scales with different lengths. Furthermore, we checked for equidistance by
comparing numerical intervals to the corresponding intervals on the VAS. Result: There is
strong evidence that data from VAS are on the level of an interval scale (see Reips & Funke,
This leads to another research question: Can the findings from Study 1 be generalized
beyond well-educated Germans?
In a second experiment, we replicated Study 1 with a US sample (n = 380) consisting of
members of a commercial online access pool representing a more diverse population from
another cultural area.
The combination of both studies allowed us to compare ratings by respondents with different
cultural backgrounds (US vs. German sample). Furthermore, we compared scale use by
respondents with different education, age and state of residence within the US sample.