The use of diagnostic tests to detect or confirm the presence of disease is a central function of clinical medicine and accounts for a large portion of health care expenditures in patient care. The increasing number, cost, and sophistication of diagnostic tests<sup>18 Fineberg H.V., Hiatt H.H. Evaluation of medical practices: The case for technology assessment N Engl J Med 1979 ;  301 : 1086

Cliccare qui per andare alla sezione Riferimenti</sup> and their impact on patient care warrant rigorous assessment and validation of new tests before they are adopted into routine clinical practice.<sup>50 Reid M.C., Lachs M.S., Feinstein A.R. Use of methodological standards in diagnostic test research. Getting better but still not good JAMA 1995 ;  274 : 645

Cliccare qui per andare alla sezione Riferimenti</sup>

Unfortunately, relatively little attention has been directed toward applying a standard methodology to the assessment of new tests despite the fundamental importance of diagnostic testing to clinical medicine. Although methodologic standards for new test evaluation exist,^{*2,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57} multiple studies indicate that those standards have been incompletely applied by investigators who study and report the accuracy of diagnostic tests.<sup>22,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 42,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 52,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 62,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 122,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 202,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 252,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 362,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 502,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti, 572,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti</sup> In one recent critical appraisal, it was noted that most diagnostic tests are inadequately evaluated in studies that promote their use.<sup>502,4,5,6,12,18,20,21,31,32,33,34,35,46,49,57

Cliccare qui per andare alla sezione Riferimenti</sup> Incomplete conformance to methodologies in diagnostic test-assessment research stands in marked contrast to the rigorous standards expected for the staged evaluation of new pharmaceutical agents or the reporting of randomized, controlled trials of new therapies.

Diagnostic test-assessment methodologies are intended to limit the introduction of potential biases into experimental design that escape the investigator's attention and thereby promote inaccurate assessment of test efficacy. In the absence of such methodologies, promising initial reports may introduce into clinical medicine diagnostic tests that subsequently prove disappointing.<sup>46 Nierenberg A.A., Feinstein A.R. How to evaluate a diagnostic marker test: Lessons from the rise and fall of dexamethasone suppression test JAMA 1988 ;  259 : 1699

Cliccare qui per andare alla sezione Riferimenti, 47 Power E.J., Tunis S.R., Wagner J.L. Technology assessment and public health Annual Review of Public Health 1994 ;  15 : 561

Cliccare qui per andare alla sezione Riferimenti, 49 Ransohoff D.F., Feinstein A.R. Problems of spectrum and bias in evaluating the efficacy of diagnostic tests N Engl J Med 1978 ;  299 : 926  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> The dexamethasone suppression test for depression<sup>46 Nierenberg A.A., Feinstein A.R. How to evaluate a diagnostic marker test: Lessons from the rise and fall of dexamethasone suppression test JAMA 1988 ;  259 : 1699

Cliccare qui per andare alla sezione Riferimenti</sup> and serum carcinoembryonic antigen determinations for colon cancer<sup>19 Fletcher R.H. Carcinoembryonic antigen Ann Intern Med 1986 ;  104 : 66

Cliccare qui per andare alla sezione Riferimenti</sup> represent two tests that were greeted with early enthusiasm and widespread application before subsequent investigations identified critical biases in the initial assessment studies. Later studies failed to support their clinical use. The premature adoption of diagnostic tests that later prove of little value both wastes health care resources and potentially harms patients by incorrectly labeling their state of health and misdirecting diagnostic and therapeutic care.<sup>18 Fineberg H.V., Hiatt H.H. Evaluation of medical practices: The case for technology assessment N Engl J Med 1979 ;  301 : 1086

Cliccare qui per andare alla sezione Riferimenti, 47 Power E.J., Tunis S.R., Wagner J.L. Technology assessment and public health Annual Review of Public Health 1994 ;  15 : 561

Cliccare qui per andare alla sezione Riferimenti</sup>

This article reviews major standards for assessing diagnostic tests to assist readers of the medical literature and investigators who are designing assessment studies. Standards are discussed in relationship to pleural-fluid tests that discriminate between exudative and transudative pleural effusions (hereafter termed exudate-transudate studies) because of the familiarity of those diagnostic tests to pulmonary physicians and their importance to clinical practice. Throughout the discussion, the important questions that clinicians should ask when considering the acceptability of a new diagnostic test will be kept in focus: (1) Are the studies supporting the use of the test valid? (2) What is the test's efficacy and diagnostic accuracy? (3) How should the test be applied to the patient at hand?