Readability of Patient-Reported Outcome Measures in Adult Speech-Language Pathology Practice

Patient-reported outcome measures (PROMs) are widely used in adult speech-language pathology to capture patient- and caregiver-perceived symptoms, functional impact, and treatment outcomes. For PROM data to be valid and equitable, end users must be able to comprehend and complete these instruments as intended. This study evaluated the readability of validated English-language PROMs used in adult speech-language pathology practice and examined variability across clinical domains.

Seventy-four validated adult speech-language pathology PROMs spanning eight clinical domains were identified from a recent scoping review and supplementary searches. Patient-facing text, including instructions, item stems, and response options, was extracted and analyzed using four readability indices: Flesch-Kincaid Grade Level, Coleman-Liau Index, Simple Measure of Gobbledygook (SMOG), and FORCAST Grade Level (FORCAST). Readability estimates were summarized descriptively and compared against a ≤ 6.0 grade-level benchmark for patient-facing health materials.

Across PROMs and domains, readability estimates frequently exceeded recommended grade-level thresholds. No PROM met the ≤ 6.0 benchmark across all four indices. When averaged across indices, only a small subset of PROMs, primarily within the language and voice domains, met recommended readability levels. Domain-level averages generally exceeded the benchmark, particularly when assessed using SMOG and FORCAST.

Validated PROMs used in adult speech-language pathology practice often require reading abilities above recommended health literacy levels, potentially limiting independent completion and equitable use. Readability should be considered alongside psychometric properties during PROM development, selection, and implementation to support accessible and patient-centered assessment.