title: Is TIRADS a practical and accurate system for use in daily clinical practice?
abstract: OBJECTIVE
  To assess the positive predictive value (PPV) and inter-observer agreement of Thyroid Imaging Reporting and Data System (TIRADS) as described by Kwak et al.
  
  
  METHODS
  This was a prospective study wherein ultrasound was performed by two radiologists on patients with thyroid nodules >1 cm. The third radiologist interpreted archived images. Ultrasound features and TIRADS category were compared with cytology and surgical histopathology. PPV was calculated for all readers' combined assessment. Inter-observer agreement was calculated using linear weighted kappa.
  
  
  RESULTS
  A total of 238 patients with 272 nodules of mean size 2.9 ± 1.7 cm were included. PPV for malignancy was 6.6%, 32%, 36%, 64%, 59%, and 91% for TIRADS 2, 3, 4a, 4b, 4c, and 5 categories, respectively. Inter-observer agreement was substantial [kappa (k) = 0.61-0.80] for assessment of nodule echogenicity, margins, calcification, and shape and good (k = 0.570, P < 0.001) for assessment of composition of the thyroid nodules. Overall agreement between observers was substantial for assigning TIRADS category [multi-rater weighted kappa coefficient (wt k) = 0.721, P < 0.001].
  
  
  CONCLUSIONS
  TIRADS is a simple and practical method of assessing thyroid nodules with high PPV and good inter-observer agreement.
authors.affiliation: Department of Radiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Anuradha
authors.initials: A
authors.lastname: Chandramohan
authors.affiliation: Department of Radiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Khurana
authors.affiliation: Department of Radiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: B T
authors.initials: BT
authors.lastname: Pushpa
authors.affiliation: Department of Pathology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Marie Therese
authors.initials: MT
authors.lastname: Manipadam
authors.affiliation: Department of Endocrinology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Dukhabandhu
authors.initials: D
authors.lastname: Naik
authors.affiliation: Department of Endocrinology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Nihal
authors.initials: N
authors.lastname: Thomas
authors.affiliation: Department of Endocrine Surgery, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Abraham
authors.affiliation: Department of Endocrine Surgery, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Mazhuvanchary Jacob
authors.initials: MJ
authors.lastname: Paul
keywords: Benign; Thyroid Imaging Reporting and Data System; malignant; thyroid nodules; ultrasound