What is the Wells score?

From the Guidelines

The Wells score is a valuable clinical prediction tool for assessing the probability of pulmonary embolism (PE) in patients, categorizing them into low, moderate, and high probability groups based on a scoring system that includes 7 variables, with a score of 0-1 indicating a low probability of PE and a score of 6 or more indicating a high probability. The Wells score assigns points for various clinical factors, including symptoms and medical history, with the goal of identifying patients who are unlikely to have PE and can be safely discharged without further testing, as well as those who require immediate diagnostic evaluation and potential treatment 1.

Key Components of the Wells Score

• The score ranges from 0 to 12, with higher scores indicating a higher probability of PE
• A score of 0-1 is associated with a low probability of PE (3.6%), while a score of 6 or more is associated with a high probability of PE (66.7%) 1
• The score can be used in conjunction with D-dimer testing to further stratify patients and reduce the need for unnecessary testing

Clinical Application of the Wells Score

• The Wells score has been validated in multiple studies as a useful tool for risk stratification in patients with suspected PE 1
• It can help clinicians identify patients who are at low risk for PE and can be safely discharged without further testing, as well as those who require immediate diagnostic evaluation and potential treatment
• The score is not truly objective, as it includes a subjective variable for "an alternative diagnosis is less likely than PE", which can be influenced by physician judgment 1

Limitations and Potential Biases

• The Wells score is not perfect and has been criticized for its subjective nature and potential for bias 1
• However, it remains a widely used and valuable tool for clinicians to assess the probability of PE in patients and make informed decisions about further testing and treatment.

From the Research

Well Score

• The Well score is a prediction rule used for pre-test probability assessment of deep vein thrombosis (DVT) 2.
• The original and modified Wells score are widely used for this purpose, and they have been compared in terms of their predictive performance in patients with suspected DVT 2.
• The study found that both scores performed equally well in predicting proximal DVT, but they were not particularly useful in hospitalized patients and those with isolated distal DVT 2.
• The original Wells score classified a higher proportion of patients as low-risk and a lower proportion as high-risk compared to the modified score 2.
• The area under the receiver operating characteristic curve regarding proximal DVT detection was similar for both scores 2.

Diagnosis and Treatment

• The diagnosis of DVT and pulmonary embolism (PE) involves the use of evidence-based algorithms and the assessment of pretest clinical probability 3.
• D-dimer tests may be used to reduce the need for subsequent diagnostic procedures 3.
• The treatment of venous thromboembolism (VTE) typically involves anticoagulation therapy, which may include the use of non-VKA oral anticoagulants such as rivaroxaban and apixaban 3, 4, 5.
• The choice of anticoagulation therapy depends on various factors, including the patient's risk of bleeding and recurrence of VTE 6.

Anticoagulation Therapy

• Anticoagulation therapy is the cornerstone of treatment for VTE, and it has been shown to reduce the risk of recurrent events and complications such as post-thrombotic syndrome and chronic thromboembolic pulmonary hypertension 4, 6.
• Non-VKA oral anticoagulants such as rivaroxaban and apixaban have been shown to be effective and safe alternatives to traditional anticoagulation therapy 4, 5.
• The optimal duration of anticoagulation therapy depends on various factors, including the patient's risk of recurrence and bleeding 6.