Developing the Review Questions and Outcomes Review questions were developed in a PICO framework (patient, intervention, comparison and outcome) for intervention reviews. This was to guide the literature searching process and to facilitate the development of recommendations by the Guideline Development Group (GDG). These were drafted by the NCGC technical team and refined and validated by the GDG. The questions were based on the key clinical areas identified in the scope (see Appendix A in the full version of the original guideline document). Due to the breadth of the scope and the target population, the GDG often found that several review questions could be generated for a single area within the scope. However, only 15 to 20 questions can be reasonably managed within the usual time frame of full clinical guideline development (18 months). Since it was not possible to cover all potentially important aspects, the GDG considered the relative importance of these and prioritized areas for developing review questions. This decision to prioritize certain areas took into consideration factors such as whether the area is a key clinical issue for the National Health Service (NHS), patient safety, cost (to the NHS), equality and variations in practice. Searching for Evidence Clinical Literature Search Systematic literature searches were undertaken to identify evidence within published literature in order to answer the review questions as per The Guidelines Manual (2009). Clinical databases were searched using relevant medical subject headings, free-text terms and study type filters where appropriate. Studies published in languages other than English were not reviewed. Where possible, searches were restricted to articles published in English language. All searches were conducted on core databases, MEDLINE, EMBASE and The Cochrane Library. Additional subject specific databases were used for some questions: CINAHL for questions on training and education, algorithms, urine output, and daily weights; PsycINFO for the training and education question. All searches were updated on 12 March 2013. No papers after this date were considered. Search strategies were checked by looking at reference lists of relevant key papers, checking search strategies in other systematic reviews and asking the Guideline Development Group (GDG) for known studies. The questions, the study types applied, the databases searched, and the years covered can be found in Appendix D in the full version of the original guideline document. This is a clinical area that presented challenges when searching for the evidence. There was no clear population for each question, as well as a lack of consistency in the terminology used in the papers and in the application of index terms in the databases. These factors tend to lead to exceptionally large searches with imprecise retrieval. There was a need to balance this with the resources available to sift through large retrievals within the time allotted. For this reason, there was extra reliance on finding evidence through methods such as checking reference lists or asking the GDG for known studies, as a supplement to the literature searches. This is in line with methodology suggested by the Cochrane Collaboration. As an extra precaution, reviewers also checked through all studies which were ordered but excluded for related reviews, to ensure that no relevant studies were missed. For example, when looking for studies for the volume and timing of resuscitation review, reviewers also checked the studies which had been ordered for the algorithm questions (there is a possibility that some algorithms effectively compare early vs. late resuscitation) and the fluid type question.
