Data extraction: After study planning, we decided to decided to included all published studies and decided not to include data that hadn't been formally published. Our search strategy with three terms related to the research question considering: patient population, intervention types of the different imaging modalities and the design type; we decided to include two types of search terms, free words and standardized words such as those use in Medical Subject Headings (MeSH) for PubMed and for EMBASE we used EMTREE terms; we also used a combination of thematic terms selected by a controlled vocabulary, the Thesaurus, open when necessary and with broad range of free text terms. As we described in detail as follows, the data extraction was always with more than two researchers. The team was divided into a searcher, a search advisor, and five junior and four senior reviewers. Four senior reviewers gathered together to define the MeSH terms necessary for the literature search. The searcher and the search advisor (one senior reviewer) worked together to build up the corresponding search algorithms as follows: for prospective or retrospective clinical trials, case series, abstracts and gray literature in English or Spanish for PubMed, for EMBASE, and for Scopus; also for meta-analysis and systemic reviews for PubMed, for EMBASE and for Scopus for the period comprised between January 1970 to December 2015. One senior author (first author) was designed as "administrator", then all retrievals from the searcher went directly and only to the administrator to avoid duplications or gaps in the review process. First the administrator received a search with titles and abstracts, which s/he distributed equally to the four senior reviewers (including the administrator) to make an initial selection and to eliminate all titles and abstracts that did not meet the inclusion or exclusion criteria, which was then gathered together by the administrator and sent back to the searcher, whose used the list of selected documents (titles and abstracts) to send a second package of searches to the administrator with all documents in full text version, who again equally distributed these documents to all four senior reviewers, who then validated the inclusion and exclusion criteria, which may have been missed in the abstract alone; the resulting package was again returned to the administrator who equally distributed the documents to all junior and senior reviewers to score each study according to the STARD checklist for this type of project. We previously established a minimum of 60% of points in the STARD checklist for a study to be approved and be included in the next stage of the review. All scoring sheets were sent back to the administrator within the timeline period. All disagreements were solved during our research meetings by a consensus of the senior reviewers. The administrator then selected the studies to be included in the meta-analysis based on the STARD score and distributed them equally to all junior and senior reviewers (including the administrator) to extract data in a pre- designed data capture sheet. At the deadline, the administrator gathered together all data capture sheets and then re-distributed equally with the original papers to the four senior reviewers who did a second review of each study to assure quality of the extracted data. All disagreements were solved during extra research meetings of the senior reviewers by consensus. After the data were accepted by the four senior reviewers, the administrator provided another senior reviewer, acting as a "statistician" with all captured data to start the statistical analysis. At the same time, all studies included in the meta-analysis were again distributed by the administrator to two senior reviewers (the administrator and the statistician) who did the data extraction for the sub-analysis, each senior reviewer took two imaging modalities for review, and after completion those sub-analysis data were gather together by the statistician to be included in the meta-analysis.