Just how Bad are Long Surveys, really? A Measurement of Data Degradation due to Length of Interview (LOI)

Editor's note: Quest Mindshare held a webinar on March 24, 2021 focusing on length of interviews and their impact on survey results. Duration: 43:37.

Everyone knows longer surveys can and do affect response rates, respondent engagement, data quality and a host of other important results. But how much? What really happens when LOIs go from five minutes to 10 minutes to 15…and beyond? Join Scott Worthge and Greg Matheson in Quest’s initial exploration in quantifying effects of increasing LOI, using an in-house Research On Research case study.  

  • Increasing LOI can have measurable effects for survey results, decreasing engagement and reliability in specific ways.
  • Learn how Quest’s first investigation into this subject yielded several expected and some unexpected results.
  • Watch for our continuation of exploring this universal survey topic, so we can arm researchers with data to discuss LOI with clients.


Moneeza Ali, Marketing Manager 
Greg Matheson, Managing Partner 
Scott Worthge, Senior Director, Research Solutions