This analysis could yield evidence-based guidelines for the use of contrast material or serve as a demonstration of what is lacking in the evidence at this time. We sought to apply such criteria to the evidence for clinical efficacy that is, to the probability that a patient will derive benefit, under optimum conditions, from contrast-enhanced MR neuroimaging. Increasingly, these financially involved entities require evidence-based practice guidelines and patient outcomes data based on rigorous technology assessment methodology. In the current environment of cost containment, an established role may not warrant continued government and corporate support for a specific technology. Most contrast material was used in neuroimaging, with an established role in lesion detection, in characterization, and in improving radiologists' confidence regarding interpretation. At an approximate hospital charge of $150 per dose, the use of contrast material accounted for almost $1 billion during the first 6 years of its clinical application. By March 1993, more than 5.4 million doses had been administered (1). Gadolinium-based MR contrast agents have been widely applied since they were first available for clinical use in 1988. Such studies are essential to devise measures of diagnostic accuracy, which can form the basis for further studies that will assess diagnostic and therapeutic impact and, ultimately, patient outcomes. On the basis of this review, we herein describe basic methods to document improvements in technology. Finally, small sample sizes with inadequate controls were presented in almost all of the articles.ĬONCLUSION: Although MR contrast media are widely used and play an essential role in lesion detection and confidence of interpretation, no rigorous studies exist to establish valid sensitivity and specificity estimates for their application. Unfortunately, the studies we reviewed commonly lacked clear descriptions of patient demographics, the spectrum of symptomatology, and the procedure for assembling the study cohort. Radiologists and clinicians need to determine the applicability of any published study to their own practices. In addition, images were not always interpreted independently from the reference standard. Specifically, a common problem was failure to establish and uniformly apply an acceptable standard of reference. In general, the Methods sections of the evaluated articles did not contain details that would allow the reader to calculate reliable measures of diagnostic accuracy, such as sensitivity and specificity. ![]() RESULTS: One hundred one of 108 articles received a D rating, six received a C rating, and one received a B rating. The readers applied objective, well-established methodological criteria to assign each article a rating of A, B, C, or D. ![]() The articles were randomly assigned to four readers (a fifth reader reviewed all of the articles) who were blinded to article titles, authors, institutions, and journals of publication. From 728 clinical studies retrieved via MEDLINE, we identified 108 articles that evaluated contrast media efficacy for a minimum of 20 patients per study. METHODS: To evaluate the reported clinical efficacy of MR contrast media in neuroimaging, we performed a critical review of the literature. This investigation seeks to define specific methodological problems in the MR contrast media literature and to suggest guidelines for an improved study design. BACKGROUND AND PURPOSE: MR contrast media are commonly used but do not have evidence-based guidelines for their application.
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