Written information about individual medicines for patients

Medicines are the most common intervention in most health services. People taking medicines need good quality information: to enable them to take and use the medicines effectively, to understand the potential harms and benefits, and to allow them to make an informed decision about taking them. Written medicines information is provided in some countries as a leaflet accompanying medicines, and is available via the Internet. Our review examined if written information about individual medicines can improve knowledge or attitudes, or change behaviours relating to taking a medicine.

The findings of this review were inconclusive for a number of reasons. First, because the included trials measured different outcomes in different ways, we were unable to combine their results. Second, these trials presented the written information for patients in different ways, and most did not design the leaflets in a way that made them easy to read. Third, in many cases trials were not clearly reported, so we do not know if they were carried out correctly. Despite these limitations several trials, while using different types of information and different measures, found written information improved knowledge. This is encouraging for people who want to learn about their medicines from leaflets. None of the studies showed that written information was harmful.

Future research needs to use improved methods, and needs to examine the same measures on many occasions. It is important that medicines information be well written and designed to maximise the possibility of improving knowledge. Consumers are increasingly seeking out health information, including information about medicines, on the internet, but we found no trials examining whether internet-based medicines information changed people's knowledge, attitudes, or behaviour.

Authors' conclusions: 

The combined evidence was not strong enough to say whether written medicines information is effective in changing knowledge, attitudes and behaviours related to medicine taking. There is some evidence that written information can improve knowledge. The trials were generally of poor quality, which reduces confidence in the results. Trials examining the effects of written information need to be better designed and use consistent and validated outcome measures. Trials should evaluate internet-based medicines information. It is imperative that written medicines information be based on best practice for its information design and content, which could improve its effectiveness in helping people to use medicines appropriately.

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Background: 

Medicines are the most common intervention in most health services. As with all treatments, those taking medicines need sufficient information: to enable them to take and use the medicines effectively, to understand the potential harms and benefits, and to allow them to make an informed decision about taking them. Written medicines information, such as a leaflet or provided via the Internet, is an intervention that may meet these purposes.

Objectives: 

To assess the effects of providing written information about individual medicines on relevant patient outcomes (knowledge, attitudes, behaviours and health outcomes) in relation to prescribed and over-the-counter medicines.

Search strategy: 

We searched MEDLINE, EMBASE, CINAHL, The Cochrane Library, PsycINFO and other databases to March 2007. We handsearched five journals' tables of contents, and the reference lists of included studies, and contacted experts in the field.

Selection criteria: 

Randomised controlled trials (RCTs) of medicine users, comparing written medicines information with no written medicines information; or trials that compared two or more styles of written medicines information. We only included trials that measured a knowledge, attitudinal or behavioural outcome. There were no language restrictions.

Data collection and analysis: 

Two review authors independently extracted data relating to the interventions, methods of the trials, and outcome measures; and reconciled differences by discussion. Heterogeneity of interventions and outcomes measured meant that data synthesis was not possible. The results are presented in narrative and tabular format.

Main results: 

We included 25 RCTs involving 4788 participants. Six of twelve trials showed that written information significantly improved knowledge about a medicine, compared with no written information. The inability to combine results means we cannot conclude whether written information was effective for increasing knowledge. The results for attitudinal and behavioural outcomes were mixed. No studies showed an adverse effect of medicines information.