Evaluating nine clinical practice guidelines for Vitamin D supplementation in children and adolescents with AGREE II: recommendations and controversies

Objective The aim of this study was to assess the quality of clinical practice guidelines(CPGs)using the Appraisal of Guidelines for Research and Evaluation Ⅱ(AGREE Ⅱ) instrument, and to provide a reference for promotion, development and adaptation of the guidelines. The recommendations were compared among guidelines for children and adolescents vitamin D supplementation, and the basic consensus and dispute were focused. Methods PubMed, Web of Science, China National Knowledge Infrastructure, Wanfang Chinese Periodical Database, VIP Chinese Periodical Database, National Guideline Clearinghouse and relevant web sites were searched for the guidelines on children and adolescent vitamin D supplementation. The common characteristics of guideline were descriptively analyzed. AGREE Ⅱinstrument was used to evaluate the quality of CPGs. Intraclass correlation coefficient (ICC) was used to examine the conformance of the raters′ evaluation scores. The recommendations of the included guidelines were extracted, analyzed and compared to find the similarities and differences. Results A total of 9 CPGs were identified from the United States, China, Canada, France, Poland and Australia/ New Zealand. The guidelines were published from 2006 to 2012, 3 of them were evidence-based (EB) and 2 used GRADE method, 1 used AHRQ evidence grading system, the rest of 6 were non-EB CPGs made by consensus of experts and article review. ①The AGREEⅡinstrument rated CPGs among 6 domains. "Scope and purpose", "clarity and presentation", and "applicability"were averagely scored ≥50%, "stakeholder involvement", "rigor of development" and "editorial independence" were scored 48%, 42% and 28% respectively and needed improved. EB CPGs had higher quality scores compared with non-EB CPGs for "rigor of development" and "editorial independence". ② The main recommendations of CPGs were similar. However, there were 5 main differences summarized among CPGs. For prevention of VD deficiency, 400 IU·d-1 of VD was considered as a safe dose for 0-1 year-old group and therefore worthy to be recommended. For treatment of VD deficiency, America(ES) CPGs recommend 2 000 IU·d-1 of VD for at least 6 weeks(1-18 years group). For sun exposure, America and Australia/New Zealand CPGs held different recommendations. For supplement of VD2 or VD3, there was no consensus among included CPGs. For 25OHD level, nearly all CPGs agreed to the increased prevalence of rickets when 25OHD 30 nmol·L-1. For pregnant and lactating women, CPGs recommend that this group should pay attention on VD supplementation, or maintain appropriate 25OHD level. Conclusions ①The overall quality of the included CPGs is still to be improved, and EB CPGs have higher quality scores for "rigor of development". ②400 IU·d-1 of VD is considered as a safe dose to preventing VD deficiency for all 0-18 years-old groups and therefore worthy to be recommended. ③The recommendations of China CPGs have absorbed the high quality CPGs from other countries, so adaptation and development of Chinese own high-quality CPGs is urgently needed.