Diagnostic value of the wells score for lower extremity deep vein thrombosis in hospitalized patients: A case–control study

Background Deep vein thrombosis (DVT) remains a frequent and potentially life-threatening complication among hospitalized patients, necessitating timely diagnosis. The Wells score is widely used for assessing DVT probability; however, its performance in inpatient populations remains uncertain. This study aimed to evaluate the diagnostic accuracy of the Wells criteria for lower extremity DVT among hospitalized patients. Methods In this case–control study conducted at two teaching hospitals between 2017 and 2020, 240 patients with confirmed DVT were compared with 240 age- and sex-matched controls without DVT. All participants underwent standardized clinical evaluation and duplex ultrasonography within 24 h of admission. Wells scores were calculated based on predefined clinical parameters. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined. Results Of 480 participants (mean age 51.9 ± 11.6 years; 54.4% female), DVT was confirmed in 240 (50%). A Wells score ≥2 classified patients as likely DVT. This threshold yielded a sensitivity of 86.3%, specificity of 70.0%, PPV of 74.2%, and NPV of 83.8%. Significant predictors included recent surgery or prolonged hospitalization ( p < 0.001), calf swelling >3 cm ( p < 0.001), and pitting edema confined to the symptomatic leg ( p < 0.001). Conclusion The Wells criteria demonstrated good sensitivity and moderate specificity for diagnosing DVT in hospitalized patients, supporting their role as an initial clinical assessment tool. However, they should not replace confirmatory testing such as ultrasonography or D-dimer assays. Larger multicenter studies are warranted to further validate these findings.