The Effect of Rating Scale Length on the Occurrence of Inappropriate Category Use for the Assessment of Job Satisfaction: an Experimental Online Study

When job satisfaction is measured in national panel surveys using a rating scale that consists of many response categories the psychometric quality of the data obtained is often reduced. One reason lies in an inappropriate category use (e.g., in terms of response styles or ignoring superfluous categories), which occurs when respondents are faced with an overwhelmingly large number of response options. The use of response styles can also be triggered by stable respondent characteristics. The objective of the present between-subject experimental study is to explore the impact of rating scale length on the occurrence of inappropriate category use and scale reliability. In addition, this study investigates which stable respondent characteristics and job-related factors consistently predict the use of a particular response style across all experimental conditions. A sample of MTurk workers (N = 7042) filled out a 12-item online questionnaire on aspects of job satisfaction, with a 4-, 6-, or 11-point rating scale randomly assigned. Considering the three-dimensional structure of the job satisfaction measure, we applied a multidimensional extension of the restricted mixed generalized partial credit model to explore category use patterns within each condition. The results show a similar configuration of three response-style classes in all conditions. Nevertheless, the proportion of respondents who used the rating scale inappropriately was lower in the conditions with fewer response categories. An exception was the extreme response style, which showed a similar prevalence rate in all conditions. Furthermore, we found that the use of extreme response style can be explained by a high level of general self-efficacy and perceived job autonomy, regardless of rating scale length. The findings of the study demonstrate that the prevalence of inappropriate category use can be reduced by administering rating scales with six or four response categories instead of eleven. These findings may be extended to other domains of life satisfaction.