The diagnostic randomized clinical trial is the best solution for management issues in critical limb ischemia

• Published in: Journal of clinical epidemiology 2004-11, Vol.57 (11), p.1111-1118
• Main Authors: de Graaff, Jurgen C., Ubbink, Dirk Th, Tijssen, Jan G.P., Legemate, Dink A.
• Format: Article
• Language: English
• Subjects: Accuracy; Ankle - blood supply; Biological and medical sciences; Blood and lymphatic vessels; Blood Gas Monitoring, Transcutaneous; Blood Pressure Determination; Cardiology. Vascular system; Critical Care - methods; Critical limb ischemia; Decision Trees; Diagnosis; Diagnostic research; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Epidemiology; Extremities - blood supply; General aspects; Humans; Hypotheses; Ischemia; Ischemia - therapy; Medical sciences; Methodology; Mortality; Oxygen - blood; Pain; Planification. Prevention (methods). Intervention. Evaluation; Public health. Hygiene; Public health. Hygiene-occupational medicine; Randomized clinical trial; Randomized Controlled Trials as Topic - methods; Side effects; Studies; Toe blood pressure; Toes - blood supply; Transcutaneous oxygen pressure
• ISSN: 0895-4356; 1878-5921
• DOI: 10.1016/j.jclinepi.2004.02.020

The value of a new diagnostic test is usually established by analyzing its accuracy in relation to a reference standard. Here we describe a potentially better model of diagnostic research, namely, a diagnostic randomized clinical trial (D-RCT), and discuss its pros and cons using management of critical limb ischemia as an example. Patients clinically suspected of critical limb ischemia are randomized either for the conventional management strategy (treating physician determines the diagnostic and therapeutic strategy on clinical judgment and ankle pressure) or new strategy (transcutaneous oxygen and toe pressure determine the diagnostic and therapeutic strategy). The effect of the diagnostic work-up on the diagnostic and therapeutic process and clinical outcome will be evaluated. A D-RCT is suited when a true reference standard is lacking. It is the best available research method to control for confounding and bias, and it also incorporates the total effect (interpretation and side effects) on clinical outcome. The D-RCT has some disadvantages, however, as to the power and size of the trial and the influence of treatment on the outcome parameter. A D-RCT can provide valuable information as to the evaluation of diagnostic tests.