Market Research: Foundations to Practice · Research Design: Choosing the Right Method
Choosing a Data Collection Mode
Online, phone, in-person, and mail modes each introduce different biases and reach different populations, and the choice is rarely neutral. This chapter covers what to weigh.
Common data collection modes include online surveys, telephone interviews, in-person interviews, and mail surveys, each with different cost, speed, reach, and bias profiles; online surveys have become the dominant mode for most commercial market research due to low cost and fast turnaround, but they are not universally appropriate for every population or question.
Key Takeaways
- Online, phone, in-person, and mail modes each have different cost, speed, reach, and bias profiles; no single mode is universally best.
- Each mode has a coverage bias: online underrepresents limited digital access, phone struggles with declining response rates, in-person is expensive and slow.
- Pew Research Center uses probability-based address sampling rather than online opt-in panels specifically to prevent self-enrollment by bad actors.
- Mixed-mode designs improve coverage but introduce mode effects, systematic differences from the collection method itself, that must be accounted for in analysis.