Quality of systematic reviews in pediatric oncology – A systematic review
Received 16 January 2009; received in revised form 21 August 2009; accepted 21 August 2009. published online 19 October 2009.
Summary
Background
To ensure evidence-based decision making in pediatric oncology systematic reviews are necessary. The objective of our study was to evaluate the methodological quality of all currently existing systematic reviews in pediatric oncology.
Methods
We identified eligible systematic reviews through a systematic search of the literature. Data on clinical and methodological characteristics of the included systematic reviews were extracted. The methodological quality of the included systematic reviews was assessed using the overview quality assessment questionnaire, a validated 10-item quality assessment tool. We compared the methodological quality of systematic reviews published in regular journals with that of Cochrane systematic reviews.
Results
We included 117 systematic reviews, 99 systematic reviews published in regular journals and 18 Cochrane systematic reviews. The average methodological quality of systematic reviews was low for all ten items, but the quality of Cochrane systematic reviews was significantly higher than systematic reviews published in regular journals. On a 1–7 scale, the median overall quality score for all systematic reviews was 2 (range 1–7), with a score of 1 (range 1–7) for systematic reviews in regular journals compared to 6 (range 3–7) in Cochrane systematic reviews (p<0.001).
Conclusion
Most systematic reviews in the field of pediatric oncology seem to have serious methodological flaws leading to a high risk of bias. While Cochrane systematic reviews were of higher methodological quality than systematic reviews in regular journals, some of them also had methodological problems. Therefore, the methodology of each individual systematic review should be scrutinized before accepting its results.
aDepartment of Pediatric Oncology, Emma Children’s Hospital/Academic Medical Center, University of Amsterdam, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands
bThe Cochrane Childhood Cancer Group, Emma Children’s Hospital/Academic Medical Center, University of Amsterdam, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands
cThe Nordic Cochrane Centre, Rigshospitalet Department 3343, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark
Corresponding author. Address: Department of Pediatric Oncology, Emma Children’s Hospital/Academic Medical Center, University of Amsterdam, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands. Tel.: +31 20 5667132; fax: +31 20 6917735.
ABSTRACT