An interesting study recently appeared in an academic journal that reports the findings of a comparative field experiment that compared the efficacy of interviewing people on mobile phones vs. fixed (land) lines. The results might surprise you.
The first survey research project I ever conducted was a phone survey in 1978! (Yes, I’m old!). I worried about a lot of things on that project — Did I draw a good sample? Did I pick the right data-gathering method? Was my questionnaire solid? Too many open-ended questions? Would the response rate be high enough? And on and on. What I DID NOT think twice about, let alone worry about, was if I would be reaching the survey participants at home, at work, or if they would be driving on a freeway, shopping in a mall or in the gym! There was no chance of reaching anyone via cell phone. There weren’t any!
That was then. And now is now. We will never go back. Every year hundreds of thousands of households give up their land (fixed) line and go mobile.
Are there differences between surveying people on a fixed line vs. a mobile phone? There sure are. And the differences might surprise you.
A recent issue of the International Journal of Market Research reported the results of an interesting comparative treatment field experiment where researchers completed 1,000 interviews on fixed lines with 1,000 interviews on mobile phones. The questionnaire was the same for both groups, allowing direct comparisons. The data they were collecting were not the focus on the analysis. The researchers were interested in the metrics of the interviews themselves – response rate, number of dials required for an interview, percentage of respondents with item omissions (don’t know/no opinion), length of interview, etc.
Some results were predictable. Some were unexpected.
- The mobile phone survey had a lower response rate then the fixed phone survey.
- The mobile phone survey required almost 3 times as many dials (call attempts) as the fixed phone survey.
- Surprisingly, the mobile phone survey respondents took longer to complete the interview than the people who talked on a fixed line. (Were they distracted?)
- And the mobile phone survey respondents were less likely to give “don’t know” or “no opinion” answers than those who took the survey on a fixed line.
There are lots of other findings in this interesting article. Their methodology was solid and the analysis was precise and complete. It’s a great read if you want to see what the future holds for those of us that conduct surveys.
