Developing and determining the face and content validity of verb semantic test for Persian - Speaking people with aphasia.

Verbs deficits add to communication challenges of people with aphasia (PWA). Tests are needed to investigate the semantic features of the verb deficits in PWA. The present study aimed to design a semantic test involving both comprehension and production of the Persian verbs, and determining its content and face validity, inter-rater, Intra-rater and test-retest reliability. Verb Semantic Test- Persian (VeST-P) with its hierarchy of difficulty was constructed; the production part involved 4 subtests of Oral Picture Naming, Naming from Spoken Definition, Naming from Written Definition, and Word Definition; the comprehension part comprised 5 subtests of Spoken Word-to-Picture Matching, Written Word-to-Picture Matching, Spoken Word Definition-to- Written Word Matching, Written Word Definition-to- Written Word Matching, and Synonym Judgment. Seventy-five speech-language pathologists (SLPs), and 10 linguists participated in the development phase of the VeST-P. Twenty healthy adults participated in the pilot study. The Intraclass Correlation Coefficient (ICC) was used to assess inter-rater, Intra-rater and test-retest reliability. The VeST-P indicated high content validity based on CVR/CVI benchmarks. Examining the face validity led to keep the confirmed items and modify or replace the non-proper items. The Wilcoxon for within-group comparisons of the hierarchy levels in each test revealed significant differences (P≤ .001). The findings indicated good to excellent Inter-rater, intra-rater, and test-retest reliability (p< 0.001). The hierarchically- set VeST-P proved appropriate, yet requiring future investigation with large sample. Additionally, further reliability research on greater sample size including PWA are desirable to prove VeST-P practicality in clinical settings.