Stuck in the middle: the use and interpretation of mid-points in items on questionnaires

Abstract

Likert-type scales are commonly used when assessing attitudes, personality characteristics, and other psychological variables. This study examined the effect of varying the number of response options on the same set of 28 attitudinal items. Participants answered items using either a 4-point scale (forced choice), a 5-point scale that included a "neither" mid-point, or a 4-point scale with an option of "no opinion" presented after the item. The questionnaire also included an item asking participants what they believe the midpoint in a scale indicated. As predicted, participants' interpretations of the midpoint varied widely with the most common responses being: "no opinion," "don't care," "unsure," "neutral," "equal/both," and "neither." The quantitative results showed that participants' levels of item endorsement varied based on the response options offered. For example, "neither" was chosen more often than "no opinion" on all of the items.

Keywords: Likert scales; measurement; mid-points; questionnaires; surveys.