How (not) to inform patients about drug use: use and effects of negations in Dutch patient information leaflets

21 August 2014

Under EU regulations, patient information leaflets (PILs) are required to be clear and understandable. Negations (e.g., not, no) are a linguistic aspect that may impact PIL comprehension, yet go unmentioned in these regulations. We conducted two studies to determine (1) how negations are used in Dutch PILs (study 1) and (2) the effects of negations on readers (study 2).
Study 1 demonstrates that negations are often used in PILs as 21.0% of clauses contain at least one negation. Study 2 demonstrates that negations decrease both actual and subjective comprehension. Negations also decrease PIL appreciation and medical adherence intentions (Pharmacoepidemiology and Drug Safety, 15 July 2014).
Click here for the abstract of the article.

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