The Cochrane Database of Systematic Reviews - Issue 3 2009

The door into The Cochrane Library on the internet (http://www.thecochranelibrary.com) opens into the world's largest collection of reports of the findings of research relevant to health and wellbeing. The Library contains the Cochrane Database of Systematic Reviews, which houses the full text for more than 3700 Cochrane reviews that have already been published, along with the detailed protocols for an additional 1900 reviews that are at earlier stages of their development. Each of the reviews answers a focussed question about the effects of healthcare interventions and includes information on the methods used, studies found, analyses done, results obtained and conclusions reached by the researchers who did the review. The Cochrane Library is re-published in full every three months and the third issue for 2009 was published in July. The results and conclusions of 90 Cochrane reviews appeared for the first time and nearly 100 of the existing reviews were updated. For 19 of these, the evidence added to the review led to changes to the earlier conclusions.

The up-to-date knowledge in Issue 3 of The Cochrane Library covers many areas of health and a wide variety of interventions. The new reviews identify effective strategies for protecting workers from loud noise (1), cast doubt on the claims that garlic can provide protection against the common cold (2), show the safety of iron supplementation for children in areas where malaria is endemic (3), and highlight the lack of reliable evidence for the protective effects of green tea against cancer (4).

Among the updated Cochrane reviews, the research shows the benefits of strength training for older adults (5), the combination of oxycodone and paracetamol for postoperative pain management (6), the treatment of pregnant women diagnosed with gestational diabetes (7), and statins for people who have had a stroke (8).

Updated Cochrane reviews also highlight the continuing lack of reliable evidence on the effects of early trophic feeding for very small babies (9), vitamin C for treating pneumonia (10), Chinese herbal medicine for premenstrual syndrome (11), and the need for practice-based interprofessional collaboration interventions to be implemented within the context of rigorous evaluation studies (12).

Several of these new and updated Cochrane reviews have been highlighted in Evidence Pods, bringing the total number of podcasts in the collection to nearly 100. The podcasts, each lasting a few minutes, are available free on the Internet. They can be listened to, saved and shared from The Cochrane Collaboration's website: http://www.cochrane.org/podcasts. In the following section, two of the Cochrane authors who recorded podcasts for earlier issues of The Cochrane Library tell us about their reviews.