Validity and Reliability of the Persian Version of Language Screening Test (LAST) for Patients in the Acute Phase of Stroke

Aphasia is one of the most common consequences of a stroke; thus, screening tests for early diagnosis of the problem are necessary when dealing with aphasia patients. One of these screening tests is the Language Screening Test (LAST). The purpose of this study was to translate, validate, and utilize this test in the Persian language for patients after stroke.

The original version of LAST was translated into Persian, and then administrated on 100 patients in the acute phase by two examiners at the patient’s bedside in order to check the inter-rater reliability. To assess the agreement between the two forms (a and b) of the LAST, Concordance Correlation Coefficient (CCC), weighted Kappa, and Intraclass Correlation Coefficient (ICC) were used. Also, the Persian version of LAST and the Western Aphasia Battery (WAB) were performed at the chronic phase with two independent examiners with blind scoring.

Inter-rater reliability between Rater 1 and Rater 2 on LAST-a and LAST-b score were very good for both phases. The CCC for LAST-a and LAST-b, respectively, were 0.874 and 0.865 for the acute phase and 0.923 and 0.927 for the chronic phase. The weighted Kappa for LAST-a and LAST-b, respectively, were 0.750 and 0.740 for the acute phase, and 0.822 and 0.846 for the chronic phase.

The obtained results showed that LAST is a very simple, fast, and valid test and can be used as a reliable tool in stroke patients. Lack of cultural and language dependency are the advantages of using this test.