title: Detectability of T1a lung cancer on digital chest radiographs: an observer-performance comparison among 2-megapixel general-purpose, 2-megapixel medical-purpose, and 3-megapixel medical-purpose liquid-crystal display (LCD) monitors.
abstract: BACKGROUND
  There has been no comparison of detectability of small lung cancer between general and medical LCD monitors or no comparison of detectability of small lung cancer between solid and part-solid nodules.
  
  
  OBJECTIVE
  To compare the detectabilities of T1a lung cancer on chest radiographs on three LCD monitor types: 2-megapixel (MP) for general purpose (General), 2-MP for medical purpose (Medical), and 3-MP-Medical.
  
  
  METHODS
  Radiographs from forty patients with T1aN0M0 primary lung cancer (27 solid nodules, 13 part-solid nodules) and 60 patients with no abnormalities on both chest X-ray and computed tomography (CT) were consecutively collected. Five readers assessed 100 cases for each monitor. The observations were analyzed using receiver operating characteristic (ROC) analysis. A jackknife method was used for statistical analysis. A P value of <0.05 was considered significant.
  
  
  RESULTS
  The average AUC for all T1a lung cancer nodule detection using the 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.86, 0.89, and 0.89, respectively; there were no significant differences among them. The average AUC for part-solid nodule detection using a 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.77, 0.86, and 0.89, respectively. There were significant differences between the 2-MP-General and 2-MP-Medical LCD monitors (P = 0.043) and between the 2-MP-General and 3-MP-Medical LCD monitors (P = 0.027). There was no significant difference between the 2-MP-Medical and 3-MP-Medical LCD monitors. The average AUC for solid nodule detection using a 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.90, 0.90, and 0.88, respectively; there were no significant differences among them. The mean AUC values for all and part-solid nodules of the low-experienced readers were significantly lower than those of the high-experienced readers with the 2 M-GP color LCD monitor (P < 0.05).
  
  
  CONCLUSIONS
  Detectability of part-solid nodules using a general-purpose LCD monitor was significantly lower than those using medical-purpose LCD monitors.
authors.affiliation: Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan h-yabu@med.kyushu-u.ac.jp.
authors.forename: Hidetake
authors.initials: H
authors.lastname: Yabuuchi
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Matsuo
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kamitani
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Mikako
authors.initials: M
authors.lastname: Jinnnouchi
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Yonezawa
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Yamasaki
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Michinobu
authors.initials: M
authors.lastname: Nagao
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawanami
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Okamoto
authors.affiliation: Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016288:Computer Terminals; D003626:Data Display; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D013902:Radiography, Thoracic / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*
keywords: Liquid crystal; digital radiography; lung cancer; observer performance; pulmonary nodule