BACKGROUND: Verification bias occurs when test findings influence the decision to perform a gold standard test. It adversely influences diagnostic test accuracy by inflating sensitivity and deflating specificity. We studied the impact of verification bias on the estimated accuracy of a test commonly used in suspected @entity2 . METHODS: We studied 534 consecutive @entity1 referred for @entity419 uptake by positron emission tomography (PET). Primary outcomes were tissue diagnoses of @entity5 and of mediastinal lymph node @entity3 . A secondary outcome was 3-year mortality. We accounted for verification bias using 2 validated methods. RESULTS: The gold standard test, namely tissue acquisition, was performed in 419 @entity1 (78%); mediastinal lymph node sampling occurred in 301 (56%). While the 410 @entity1 with PET-diagnosed stage I @entity5 or higher were more likely than @entity1 with negative PET scan findings to undergo tissue diagnosis testing (92% vs 34%) (P<.001), there was no association between PET findings and performance of mediastinal sampling. Without accounting for verification bias, the sensitivity and specificity of PET for diagnosis of @entity5 were 0.95 (95% confidence interval [CI], 0.92-0.97) and 0.31 (95% CI, 0.21-0.42), respectively. After adjustment, sensitivity fell to 0.85 (95% CI, 0.81-0.89), while specificity increased to 0.51 (95% CI, 0.40-0.60). For diagnosis of @entity3629 , verification bias had slight effects on test accuracy. There were 224 deaths, with a strong gradient between PET stage and death (P<.001). CONCLUSION: The diagnostic accuracy of PET for assessment of suspected @entity2 is substantially affected by verification bias.

@entity419 uptake by positron emission tomography for diagnosis of suspected XXXX : impact of verification bias.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity419 :: ('MESH:D019788', 'Chemical') :: ['[(18)F]fluorodeoxyglucose'] @entity3629 :: ('MESH:D008477', 'Disease') :: ['mediastinal disease'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity2 :: ('MESH:D008175', 'Disease') :: ['lung cancer'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastases']
@entity2 :: (MESH:D008175,Disease) :: ['lung cancer']
