Key result
D-dimer testing was superior to strain gauge plethysmography for excluding DVT in low-risk ambulant patients, with a negative predictive value of 100% versus 95.6%.
Why the study?
Does D-dimer testing or strain gauge plethysmography better exclude deep-vein thrombosis in ambulant outpatients?
Cross-Sectional (n=243)
Does D-dimer testing or strain gauge plethysmography better exclude deep-vein thrombosis in ambulant outpatients?
D-dimer testing is superior to strain gauge plethysmography for rapidly excluding DVT in low-risk ambulant patients, and combining the two modalities does not improve clinical decision making.
Supports preferring D-dimer testing to exclude DVT in low-risk outpatients; hypothesis-generating and requires prospective validation before practice change.
There has been a significant increase in the amount of diagnostic testing performed to confirm or refute a diagnosis of deep-vein thrombosis (DVT), often in low-risk patients. D-dimer testing and computer-assisted strain gauge plethysmography (SGP) are rapid, inexpensive methods of excluding DVT and, in combination with a clinical probability score for DVT, both have been used to accurately exclude DVT. D-dimer testing, SGP and a combination of both in excluding DVT were compared in 243 ambulant outpatients who followed a prespecified investigation protocol. The negative-predictive value of D-dimer testing alone was 100%, 93.9% (95% CI 93.6-94.1) and 80% (95% CI 73.7-86.3) in patients with a low, moderate and high pretest probability (PTP) score for DVT respectively. The corresponding results for SGP were 95.6% (95% CI 95.5-95.7), 86.1% (95% CI 85.9-86.4) and 77.8% (95% CI 75.9-79.7) in patients with a low, moderate and high PTP score for DVT respectively. D-dimer testing provided a rapid, cost-effective method for excluding DVT in low-risk ambulant patients, which was superior to SGP. Combined use of the modalities did not improve any aspect of clinical decision making.
No takes yet. Share an insight, caveat, or question.
Williams et al. (2005) conducted a cross-sectional in Deep-vein thrombosis (n=243). D-dimer testing vs. Computer-assisted strain gauge plethysmography (SGP) was evaluated on Negative-predictive value in patients with a low pretest probability score for DVT. D-dimer testing was superior to strain gauge plethysmography for excluding DVT in low-risk ambulant patients, with a negative predictive value of 100% versus 95.6%.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: