Applying Multiple Methods to Assess the Readability of a Large Corpus of Medical Documents

Medical documents provided to patients at the end of an epi-sode of care, such as discharge summaries and referral let-ters, serve as an important vehicle to convey critical infor-mation to patients and families. Increasingly, healthcare insti-tutions are also experimenting with granting patients direct electronic access to other types of clinical narratives that are not typically shared unless explicitly requested, such as pro-gress notes. While these efforts have great potential to im-prove information transparency, their value can be severely diminished if patients are unable to read and thus unable to properly interpret the medical documents shared to them. In this study, we approached the problem by contrasting the ‘readability ’ of two types of medical documents: referral let-ters vs. other genres of narrative clinician notes not explicitly intended for direct viewing by patients. To establish a baseline for comparison, we also computed readability scores of Med-linePlus articles—exemplars of fine patient education materi-als carefully crafted for lay audiences. We quantified docu-ment readability using four different measures. Differences in the results obtained through these measures are also dis-cussed