The Public Opinion Survey of Human Attributes-Stuttering (POSHA-S) and Bipolar Adjective Scale (BAS): Aspects of validity

Abstract

PurposeIn order to estimate instrument validity, attitudes toward stuttering measured by the newly developed Public Opinion Survey of Human Attributes-Stuttering (POSHA-S) and the Woods and Williams (1976) semantic differential scale (referred to herein as the Bipolar Adjective Scale [BAS]) are compared in college students on one occasion as well as before and after coursework on fluency disorders. MethodUndergraduate and graduate students (n=321) from four universities filled out online versions of the POSHA-S and BAS. Two-thirds were speech-language pathology (SLP) majors; one-third were students in other majors. A subset of the SLP students (n=35) filled out the two instruments again after 8–13 weeks of coursework on fluency disorders. ResultsCorrelations between all ratings of the POSHA-S and BAS were run for the 321 students. Only 26% of the correlations were statistically significant (R≥±0.129), and the large majority of these reflected small relationships. POSHA-S ratings were correlated with up to 77% of the items of the BAS while BAS items were correlated with up to 45% of the POSHA-S ratings. After coursework on stuttering, students’ attitudes improved on both instruments, but more on the POSHA-S than the BAS. ConclusionsGreater evidence of discriminant validity than convergent validity characterized the POSHA-S and BAS. Both measures showed improved attitudes after fluency disorders coursework, but more so for the POSHA-S, confirming previous reports of construct validity. The POSHA-S taps relevant constructs not included in the BAS, which provide advantages for intracultural, international, and other comparisons of public attitudes toward stuttering.Learning outcomes: The reader will be able to: (1) describe differentiating characteristics of the POSHA-S and BAS as measures of public attitudes toward stuttering, (2) describe the overlap and lack of overlap in the constructs measured by POSHA-S and BAS, (3) describe discriminant versus convergent validity and (4) describe advantages of the POSHA-S and BAS in various types of comparative studies of stuttering attitudes.