# How accurate is Wells score for PE?

## How accurate is Wells score for PE?

Wells score >4 had a sensitivity of 40%, specificity of 87%, positive predictive value of 59%, and negative predictive value of 77% to predict risk of PE. Conclusions: In this population of critically ill patients, Wells and revised Geneva scores were not reliable predictors of PE.

## How many points does high risk pulmonary embolism have according Wells score system?

Modified Wells Scoring System

Clinical Characteristic Score
Clinical Probability of Pulmonary Embolism Score
Low 0-1
Intermediate 2-6
High ≥6

What is the probability of a PE in a patient with a Wells score of 1?

Narration of the flowchart: Wells scores (Table 1) of 0-2 are considered low PE probability (<3.6% risk of PE). Scores of 3-6 points are considered moderate PE probability (<20.5% risk of PE) and scores of 6 points or greater indicate a high probability for PE (up to 66.7% risk of PE).

### What is a pretest probability for DVT?

The rates of DVT according to pre-test probability scores in the derivation and validation cohorts were 7% and 6% in the low (score = 0-2), 23% and 22% in the intermediate (score = 3-4), and 47% and 50% in the high probability group (score ≥ 5), respectively (p < 0.0001).

### What is PE pretest probability?

Prevalence of PE in the low, moderate and high pretest probability groups categorized by physicians in training alone was 3% (95% confidence interval (CI): 1% to 9%), 31% (95% CI: 22% to 42%) and 100% (95% CI: 61% to 100%) respectively.

When do you use Wells score?

The Wells’ DVT Criteria can be used in the outpatient and emergency department setting. By risk stratifying to low risk (Wells’ Score <2) and a negative d-dimer the clinician can exclude the need for ultrasound (US) to rule out DVT. The Wells’ Deep Vein Thrombosis (DVT) Criteria risk stratify patients for DVT.

## What is 2 level Wells score?

two level Wells score for DVT

Factor Points
collateral superficial veins (non-varicose) 1
pitting oedema (confined to symptomatic leg) 1
swelling of entire leg 1
localised tenderness along distribution of deep venous system 1

## What is a high pretest probability for PE?

The Geneva score obtained relates to the probability of PE: 0 – 3 points indicates low probability (8%) 4 – 10 points indicates intermediate probability (28%) 11 points or more indicates high probability (74%)

What is VTE score?

VTE risk is categorized as being very low (0-1 point), low (2 points), moderate (3-4 points), or high (≥ 5 points). In contrast to the Rogers Score, this model (the Caprini Score) is relatively easy to use and appears to discriminate reasonably well among patients at low, moderate, and high risk for VTE.

### What is a high pretest probability?

High pretest probability was defined as: dichotomized Wells Score>4 points and patients with trichotomized Wells Score>6 points.

### What is high pretest probability?

The higher the pretest probability, the more likely one is to experience a positive test. Conversely, a negative test is less likely as the pretest probability increases. The posttest probability depends on the sensitivity and the false-positive rate of the diagnostic test.

What is the difference between a DVT and a VTE?

Venous thromboembolism (VTE), also known as blood clots, is a disorder that includes deep vein thrombosis and pulmonary embolism. A deep vein thrombosis (DVT) occurs when a blood clot forms in a deep vein, usually in the lower leg, thigh, or pelvis.

## How do you assess the risk of a DVT?

Algorithm for deep venous thrombosis (DVT) evaluation using the 3 risk stratification Wells criteria: low risk. For moderate pretest probability (Wells score 1-2), a D-dimer is recommended….Risk Stratification.

Probability (3 Risk Group) Total Score # Probability of DVT %
Low risk 0 5%
Moderate risk 1-2 17%
High risk >2 53%

## What is a good post-test probability?

If a straight line is drawn from the pretest probability of 10% through the likelihood of ratio result of 20, we are left with a posttest probability of about 70%. This means that the probability of the patient having the disease increases from 10% to 70% with a positive test result.

What percent of DVT become PE?

Data synthesis: Among patients presenting with DVT, the rate of fatal PE during anticoagulant therapy was 0.4% (95% confidence interval [CI], 0.2%-0.6%); following anticoagulant therapy it was 0.3 per 100 patient-years (95% CI, 0.1-0.8).

### What is a Caprini score of 4?

Score = 4: High risk of VTE.

### What is Post probability percentage?

Post-test probability : It is the probability of the patient having a disease after obtaining the test results (7). 2.6. Example 1: If the prevalence of disease X among a certain population is 25%, the pre-test probability of this disease will be 0.25.

Is there a correlation between Wells score and DVT?

A linear correlation was present between Wells score and DVT with R 2 = 0.88 (p = 0.0016). Median Wells score of patients without DVT was 1 (1–3) compared to a median score of 2 (1–5) in those with DVT (p < 0.0001).

## When should the Wells’ DVT criteria be applied?

The Wells’ DVT criteria should only be applied after a detailed history and physical is performed. The Wells’ DVT criteria should only be applied to those patients who have been deemed at risk for DVT. If there is no concern for DVT than there is no need for risk stratification.

## How accurate is the diagnostic probability for DVT?

“Diagnostic accuracy for DVT improves when clinical probability is estimated before diagnostic tests. Patients with low clinical probability on the predictive rule have prevalence of DVT of less than 5%.

Does the Wells rule rule out deep venous thrombosis in primary care?

The Wells rule does not adequately rule out deep venous thrombosis in primary care patients. Ann Intern Med. 2005 Jul 19;143 (2):100-7.