Abstract/Text: BACKGROUND: When ultrasonography is used to investigate deep-vein thrombosis, serial testing is recommended for those who test negative initially. Serial testing is inconvenient for patients and costly. We aimed to assess whether the calculation of pretest probability of deep-vein thrombosis, with a simple clinical model, could be used to improve the management of patients who present with suspected deep-vein thrombosis.
METHODS: Consecutive outpatients with suspected deep-vein thrombosis had their pretest probability calculated with a clinical model. They then underwent compression ultrasound imaging of proximal veins of the legs. Patients at low pretest probability underwent a single ultrasound test. A negative ultrasound excluded the diagnosis of deep-vein thrombosis whereas a positive ultrasound was confirmed by venography. Patients at moderate pretest probability with a positive ultrasound were treated for deep-vein thrombosis whereas patients with an initial negative ultrasound underwent a single follow-up ultrasound 1 week later. Patients at high pretest probability with a positive ultrasound were treated whereas those with negative ultrasound underwent venography. All patients were followed up for 3 months for thromboembolic complications.
FINDINGS: 95 (16.0%) of all 593 patients had deep-vein thrombosis; 3%, 17%, and 75% of the patients with low, moderate, and high pretest probability, respectively, had deep-vein thrombosis. Ten of 329 patients with low pretest probability had the diagnosis confirmed, nine at initial testing and one at follow-up. 32 of 193 patients with moderate pretest probability had deep-vein thrombosis, three diagnosed by the serial (1 week) test, and two during follow-up. 53 of 71 patients with high pretest probability had deep-vein thrombosis (49 by the initial ultrasound and four by venography). Only three (0.6%) of all 501 (95% CI 0.1-1.8) patients diagnosed as not having deep-vein thrombosis had events during the 3-month follow-up. Overall only 33 (5.6%) of 593 patients required venography and serial testing was limited to 166 (28%) of 593 patients.
INTERPRETATION: Management of patients with suspected deep-vein thrombosis based on clinical probability and ultrasound of the proximal deep veins is safe and feasible. Our strategy reduced the need for serial ultrasound testing and reduced the rate of false-negative or false-positive ultrasound studies.

Abstract/Text: BACKGROUND: Hypothyroidism is a common, potentially treatable endocrine disorder. Since hypothyroidism is not always associated with the signs and symptoms typically attributed to it, the diagnosis is often missed. Conversely, patients with typical signs and symptoms may not have the disease when laboratory tests are performed.
AIMS: We aimed to determine the accuracy of physical examination in the diagnosis of hypothyroidism.
SETTING AND DESIGN: Prospective, hospital-based, cross-sectional diagnostic study.
MATERIAL AND METHODS: Consecutive outpatients from the medicine department were screened and an independent comparison of physical signs (coarse skin, puffy face, slow movements, bradycardia, pretibial oedema and ankle reflex) against thyroid hormone assay (TSH and FT4) was performed.
STATISTICAL ANALYSIS: Diagnostic accuracy was measured as sensitivity, specificity, positive likelihood ratios, negative likelihood ratios and positive and negative predictive values.
RESULTS: Of the 1450 patients screened, 130 patients (102 women and 28 men) underwent both clinical examination and thyroid function tests. Twenty-three patients (18%) were diagnosed to have hypothyroidism by thyroid hormone assays. No single sign could easily discriminate a euthyroid from a hypothyroid patient (range of positive likelihood ratio (LR+) 1.0 to 3.88; range of negative likelihood ratio (LR-): 0.42 to 1.0). No physical sign generated a likelihood ratio large enough to increase the post-test probability significantly. The combination of signs that had the highest likelihood ratios (coarse skin, bradycardia and delayed ankle reflex) was associated with modest accuracy (LR+ 3.75; LR- 0.48).
CONCLUSION: Clinicians cannot rely exclusively on physical examination to confirm or rule out hypothyroidism. Patients with suspected hypothyroidism require a diagnostic workup that includes thyroid hormone assays.