Roland Brian Büchter|Dennis Fechtelpeter|Marco Knelangen|Martina Ehrlich|Andreas Waltering
Words or numbers? Communicating risk of adverse effects in written consumer health information: a systematic review and meta-analysis
Institute for Quality and Efficiency in Health Care|Institute for Quality and Efficiency in Health Care|Institute for Quality and Efficiency in Health Care|Institute for Quality and Efficiency in Health Care|Institute for Quality and Efficiency in Health Care
various types framing influence risk perceptions may impact treatment decisions adherence one way framing use verbal terms communicating probabilities treatment effects systematically reviewed comparative effects words versus numbers communicating probability adverse effects consumers written health information nine electronic databases searched november 2012 teams two reviewers independently assessed studies inclusion criteria randomised controlled trials verbal versus numerical presentation context written consumer health information ten trials included participants perceived probabilities presented verbal terms higher numeric terms commonly used verbal descriptors systematically led overestimation absolute risk adverse effects range means 3 54 numbers also led overestimation probabilities overestimation smaller 2 20 difference means ranged 38 459 one comparison showing significant results use numbers increased satisfaction information md 048 ci 032 063 p 000001 i2 0 likelihood medication use md common side effects 145 ci 078 211 p 00001 i2 68 md common side effects 090 ci 061 119 p 000001 i2 1 md rare side effects 039 002 076 p 004 i2 applicable outcomes measured 6point likert scale suggesting small moderate effects verbal descriptors including common uncommon rare lead overestimation probability adverse effects compared numerical information used previously suggested european commission numbers result accurate estimates increase satisfaction likelihood medication use review suggests providers consumer health information quantify treatment effects numerically future research focus impact personal contextual factors use representative samples conducted real life settings measure behavioral outcomes address whether benefit information described verbally