Combining quality and quantity. A psychometric evaluation of the self-anchoring scale

• DOI: 10.1007/s11135-007-9154-7
• Publication Date: 2008-01-03T15:17:56Z
• Authors: Joeri Hofmans; Peter Theuns; Frederik Van Acker
• Keywords: Anchoring

In this study a psychometric comparison is made between a category rating scale with fixed anchors and a self-anchoring category rating scale where respondents themselves define the end anchors by referring to their personal experiences with the construct being measured. A student-satisfaction questionnaire was administered to 301 undergraduate students on two test moments separated by a 1-month period. Both types of category rating scales were crossed with both test moments according to a 2 × 2 mixed factorial design. Our results show that respondents perceive the construct being measured in the same way with both rating scales. A comparison concerning different indicators of reliability, i.e. test–retest reliability, internal consistency and the error variances associated with each item, also failed to find a difference between both rating scales. In a last analysis it is demonstrated that using a self-anchoring rating scale or a rating scale with fixed anchors has a small but significant effect on the ratings of the respondents. In conclusion, a self anchoring scale may be the scale of choice if additional qualitative information from the anchors is warranted, but when quantitative comparisons between groups are required, rating scales with fixed anchors are preferable thanks to their ease of use.