title: Quantitative measurements of medical images for pharmaceutical clinical trials: comparison between on-site and off-site assessments.
abstract: OBJECTIVE
  In pharmaceutical clinical trials, quantitative measurements on medical images are often conducted to confirm drug efficacy. This study aims to compare the quantitative image analysis performance of an off-site core laboratory with the performance of investigators from multiple clinical sites.
  
  
  METHODS
  In a phase I clinical trial, 25 healthy subjects underwent dynamic brain single-photon emission computed tomography (SPECT) scintigraphy with 123I-Altropane, a cocaine analogue with high affinity and selectivity for dopamine transporter sites in the striatum. In 20 patients examined on-site and off-site, a total of 80 measurements were made to calculate the drug's binding potential. A trained technologist off-site at a central core laboratory and on-site investigators at different clinical sites performed the image analysis. These results were compared with measurements made by a subspecialty radiologist whose assessments were the reference standard. Statistical analysis was performed using multiple regression analysis.
  
  
  RESULTS
  Measurements from the central core laboratory (off-site) highly correlated (r = 0.95) with measurements of the reference standard. Measurements from the clinical sites (on-site) grouped together had lower correlation (r = 0.84) with the reference standard. This difference was statistically significant (p < 0.05).
  
  
  CONCLUSIONS
  Training and experience in the specific type of image analysis are critical in obtaining consistent data. Quantitative analysis by dedicated personnel at a core laboratory provides highly reproducible results. The findings support off-site assessment of medical images in pharmaceutical clinical trials.
authors.affiliation: Department of Radiology, Harvard Medical School and Massachusetts General Hospital, Boston 02114, USA.
authors.forename: D
authors.initials: D
authors.lastname: Sahani
authors.forename: S
authors.initials: S
authors.lastname: Saini
authors.forename: G A
authors.initials: GA
authors.lastname: Fatuga
authors.forename: E F
authors.initials: EF
authors.lastname: Halpern
authors.forename: M E
authors.initials: ME
authors.lastname: Lanser
authors.forename: J B
authors.initials: JB
authors.lastname: Zimmerman
authors.forename: A J
authors.initials: AJ
authors.lastname: Fischman
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging*; D002986:Clinical Trials as Topic / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015899:Tomography, Emission-Computed, Single-Photon / Q000706:statistics & numerical data