Toward a more valid account of functional text quality: The case of the patient information leaflet.

Patient drug and treatment information leaflets are an important adjunct to primary health care for medical practitioners to use with patients. To assess comprehensibility of these documents, readability formulas are still used by medical researchers but are arguably of limited value. Checklists to guide the development of printed information, even when based on a systematic review of the literature, have not provided the desired guidance. An approach based on a systemic functional linguistics framework is offered here as one that can provide insight and directions for the improvement of these materials. A set of 18 rheumatology drug leaflets was analyzed at the levels of genre, discourse semantics, and some aspects of the lexicogrammar, so as to identify their characteristics and possible shortcomings as comprehensible documents for patients. While the drug information leaflet was identifiable as a genre with potentially up to nine structural moves, there was a high degree of variability in inclusion of moves, rhetorical functions within moves, and use of headings. The quality of patient information material can be improved by using an analysis that takes account of suitability of generic structure and rhetorical functions, specialization of lexis, status relations, macro-Theme, lexical density, and modalization. A usability strategy should be employed to support the directions provided by the analysis. [ABSTRACT FROM AUTHOR]