Trans Group: TERE, BELLE, CHEV, ROG Edited By: Subject: Topic: Lecturer: Date: RESEARCH CRITICAL APPRAISAL OF MEDICAL JOURNAL 2 Dr. Jose Luisito A. Zulueta, M.D. September 11, 2013 Page 1 of 5 OUTLINE CRITERIA I. VALIDITY CRITERIA II. RESULTS CRITERIA III. APPLICABILITY CRITERIA OBJECTIVES At the end of the lecture, the student should be able to: 1. Enumerate the criteria used to appraise an article on diagnosis. 2. Explain the important points in the criteria used. 3. Appraise published research and judge its reliability. References: Dr. Zulueta’s PPT: • Katz, D.L., Elmore, J.G., Wild, D.M.G., Lucan, S.C., Jekel’s Epidemeology, Biostatistics, and Preventive Medicine, Third Edition, W.B. Saunders Co., USA, 2014 • Longo, D., Fauci A., Kasper D., Hauser S., Jameson, J.L., Loscalzo, J., Harrison’s Principles of Internal Medicine, 18 th Edition, McGraw[Hill Companies, USA, 2012. • Zulueta FM, Perez JR, Methods of Research, Thesis Writing, and Applied Statistics, National Bookstore, Philippines, 2009. Legend: Italicized – quoted from the lecturer CRITERIA VALIDITY CRITERIA • Was there an independent blind comparison with a reference standard? ! INFORMATION BIAS • Did the patient sample include an appropriate spectrum of patients to whom the diagnostic test will be applied in clinical practice? ! SELECTION BIAS • Did the results of the test being evaluated influence the decision to perform the reference standard? ! MISSING DATA BIAS • Were the methods for performing the test described in sufficient detail to permit replication? The reference standard is also the gold standard. If that particular test would yield a positive result, then most likely the patient has the disease. RESULTS CRITERIA • Are likelihood ratios for the test results presented or data necessary for their calculation provided? APPLICABILITY CRITERIA • Will the reproducibility of the test result and its interpretation be satisfactory in my setting? • Are the results applicable to my patient? • Will the results change my management? • Will patients be better off as a result of the test? I. VALIDITY CRITERIA 1. Was there an independent & blind comparison with a reference standard? To Avoid Information Bias (see blinding) • Comparator test should be the gold standard • Comparison should be “blind” • Procedure should be described in sufficient detail 1) Gold Standard What is a gold standard? • The accepted definition of disease [ presence or absence • Test that is 100% sensitive and 100% specific or as close as one can get to 100% Examples: • Ovarian CA " Histopath • PTB " DSSM (Direct Sputum Smear Microscopy) 2) BLINDING • Person/s doing the diagnostic test & person/s doing gold standard should be unaware of each other’s results o Test results are objective ex. Hormone assays " “Machine” interpretation Person/s doing the diagnostic test and the gold standard should be unaware of each other’s results. That is why some clinicians prefer the hormone assay because this is a test which has machine interpretation. There is objectivity in them. Effect of nonYblinding: Test seems better than it really Is (Overestimate of accuracy) APPRAISAL: Was there an independent & blind comparison with a reference standard? YES 2. Did the patient sample include an appropriate spectrum of patients to whom the diagnostic test will be applied in clinical practice? To Avoid Selection Bias • Subjects should be representative of those to which the test will be applied in clinical practice 1) Appropriate spectrum • Represent ALL types of patients to which the test will be applied in clinical practice # Type of disease $ Benign & malignant $ Specific disease subtypes # Severity of disease $ Non[palpable & palpable $ Early & advanced $ Stage I, II, III, IV In appropriate spectrum, we want a diagnostic test to be able to catch the disease in its earlier stages.
