title: Sources of variability in fluorescence spectroscopic measurements in a Phase II clinical trial of 850 patients.
abstract: BACKGROUND
  Devices using fluorescence spectroscopy to differentiate high grade squamous intraepithelial lesions from normal tissue in the cervix have shown some diagnostic efficacy. Measurements from these devices produce large amounts of complex, multi-factored data. The purpose of this study is to isolate the effects of the particular care providers and equipment operators who are involved in taking measurements.
  
  
  METHODS
  Data from spectroscopic measurements of the Phase II study of 850 patients with abnormal Papancicolau smears were used. The data were subject to a Principal Components Analysis and to MANOVA to control for variables that are known to affect outcomes.
  
  
  RESULTS
  The analysis showed significant provider effects from both devices and significant operator effects from one device.
  
  
  CONCLUSIONS
  We will repeat a similar analysis on data from a screening trial, on the combined diagnostic and screening study, and on the reflectance data. In the future, we hope to be able to design devices that address provider and operator effects.
authors.affiliation: Carnegie Mellon University, Department of Statistics, Pittsburgh, PA 15213, USA.
authors.forename: Jong Soo
authors.initials: JS
authors.lastname: Lee
authors.forename: Michele
authors.initials: M
authors.lastname: Follen
authors.forename: Calum
authors.initials: C
authors.lastname: MacAulay
authors.forename: Brian
authors.initials: B
authors.lastname: Pikkula
authors.forename: Dan
authors.initials: D
authors.lastname: Serachitopol
authors.forename: Roderick
authors.initials: R
authors.lastname: Price
authors.forename: Dennis
authors.initials: D
authors.lastname: Cox
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008875:Middle Aged; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis*