Diagnosis of developmental language disorder in research studies

Purpose: The aim of this study was to investigate the extent to which researchers in the field of developmental language disorder are utilizing validated methods to diagnose their research participants. Method: We examined 90 research articles published from 2015 to 2019 that included English-speaking participants from the United States who were identified as having a developmental language disorder or specific language impairment. From these articles, we identified the tests and measures used to identify participants and classify them as healthy or impaired. We then consulted the test manuals and the literature to find information on sensitivity and specificity of the test and the evidence-based cut score that maximized identification accuracy. Results: Of the 90 articles examined, 38 (42%) were found to reflect validated diagnostic methods, and 51 (58%) did not. Conclusion: Our results illustrate that validated methods are used less than half of the time even by those who should have a high level of expertise and despite calls for increasing scientific rigor in research practices.