The 20th anniversary of The Cochrane Collaboration takes place in 2013, and around the world, members of the Collaboration are taking this as an opportunity to reflect on the past, present and future of this wonderful and unique organization. The question of how Cochrane has contributed to child health over the past 20 years, and how this contribution can be amplified over the coming years, is one we will explore in Evidence-Based Child Health throughout 2013. One key way in which the Cochrane Child Health Field has contributed to moving forward child health evidence is through the production of the overviews of reviews that are published in this journal. Our first overview, published in Volume 1, Issue 1 of EBCH back in 2006, was the first Cochrane overview published by an entity of the Collaboration. We have continued to publish overviews ever since then. Our readers seem to agree with us that these novel articles are of interest because the overviews are the most consistently downloaded part of the journal. We have worked closely with others within the Collaboration to test, refine and move forward the methods for this important new form of evidence synthesis.
Therefore, it seems appropriate to start off Year 20 of the Collaboration, and Year 8 of our journal, by reflecting on the evolution of overviews. Accordingly, we are publishing an article by Thomson et al. which could be called an ‘overview of overviews’—an analysis of the 29 EBCH overviews with a specific focus on how they have been made to be as clinically relevant as possible1. This has been achieved by means such as: cutting across the boundaries of Cochrane Review Groups for the selection of topics; selecting topics that are clinically relevant, even though they may not match with the topics in the included systematic reviews (SRs); bringing the evidence up to date by including trials that are not included in the SRs selected for the overview and using age-subgroup analyses to present the data in a way which matches the stages of childhood development.
A frequent problem in developing child is functional constipation which seems to be much more common. It is often difficult to treat, with over half of children needing prolonged courses of medication. After the arrival of polyethylene glycol solutions, there has been a marked increase in research in this area. The review by Gordon et al. confirms the superiority of this medication when compared with placebo, lactulose and milk of magnesia2. The commentary by Tabbers and Benninga broadly agrees with the conclusion but highlights the limitations of the included studies such as the short-term follow-up of effectiveness and safety outcomes3.
Long-term follow-up is particularly important when adding nutritional supplements to a child's diet. Micronutrient deficiencies, especially iron, vitamin A and zinc, are common problems in the resource-poor areas of the world and affect several million children. While it takes time to correct the roots of this problem (poverty, poor education, sanitation), it seems logical to provide micronutrient powders to immediately correct the deficiencies in the diet. These micronutrient powders (also called “Sprinkles”) have been implemented worldwide but evidence for their effectiveness has been unclear. The review by De-Regil et al. attempts to analyse this evidence and concludes that micronutrient powders are effective in reducing anaemia but little is known about the effects on vitamin A and zinc4. The commentary by Lazzerini adds to the debate raising concerns about the safety of iron in malaria-prone areas, the optimal combination of nutrients and difficulties in achieving adherence5. The underlying message is to always be careful of preventive care that involves an intervention as it may have unintended consequences.
Preventive phototherapy in preterm and low birth weight infants seems to be one manoeuvre that has several benefits. The review by Okwundu et al. studied nine clinical trials where phototherapy was initiated in low birth weight infants within 36 hours of life6. They showed that there was a reduced need for exchange transfusion and a decreased likelihood of neurodevelopmental impairment. Davis comments that these are likely small (but important) benefits in an intervention that appear to have a low risk of harm7. Further studies are still needed using more modern phototherapy equipment and in the infants in the 501–750 g birth weight group.
Finally, developmental dysplasia of the hip screening is scrutinized by Shorter et al. in their Cochrane review8. In this paper, the authors assessed whether routine ultrasonography of the newborn hip would prove to be beneficial in earlier detection and perhaps yield a better outcome. Ultrasound screening did increase detection and treatment but unfortunately there was no difference from those diagnosed later in the need for surgery. Worryingly, the possibility of early diagnosis of mild (and possibly self-resolving) developmental dysplasia of the hip is that it leads to treatment and the chance of avascular necrosis as a complication of abduction splinting. In a thoughtful commentary by Kemper and echoed by a response from the authors, clinicians are encouraged to discuss and clarify all the risks and benefits of screening9.
I hope you enjoy this issue and, as always, comments are welcome at firstname.lastname@example.org