Web Survey Bibliography
A recent experiment tested the impact of the length of cell phone interviews. Half of the respondents in a cell phone only sample were administered a short survey of approximately 10 minutes and half were administered a longer survey of approximately 18 minutes. The response rates were similar between the two experimental groups. This suggests that once the initial challenge of getting a cell phone respondent to agree to do the interview is met, researchers can run longer interviews with minimal effect on reported response rates.
Homepage (abstract)