D-dimer strategy v repeated US in suspected DVT with negative results on proximal vein US and no DVT on initial testing*
| Outcome at 6 months | D-dimer | Repeated US | RRI (95% CI) | NNH |
|---|---|---|---|---|
| *DVT = deep venous thrombosis; US = ultrasonography. Other abbreviations defined in glossary; RRI, NNH, and CI calculated from data in article. | ||||
| Symptomatic DVT | 2.1% | 1.3% | 64% (−43 to 372) | Not significant |