title: Analysis of variance in spectroscopic imaging data from human tissues.
abstract: The analysis of cell types and disease using Fourier transform infrared (FT-IR) spectroscopic imaging is promising. The approach lacks an appreciation of the limits of performance for the technology, however, which limits both researcher efforts in improving the approach and acceptance by practitioners. One factor limiting performance is the variance in data arising from biological diversity, measurement noise or from other sources. Here we identify the sources of variation by first employing a high throughout sampling platform of tissue microarrays (TMAs) to record a sufficiently large and diverse set data. Next, a comprehensive  set of analysis of variance (ANOVA) models is employed to analyze the data. Estimating the portions of explained variation, we quantify the primary sources of variation, find the most discriminating spectral metrics, and recognize the aspects of the technology to improve. The study provides a framework for the development of protocols for clinical translation and provides guidelines to design statistically valid studies in the spectroscopic analysis of tissue.
authors.affiliation: Department of Computer Science, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
authors.forename: Jin Tae
authors.initials: JT
authors.lastname: Kwak
authors.forename: Rohith
authors.initials: R
authors.lastname: Reddy
authors.forename: Saurabh
authors.initials: S
authors.lastname: Sinha
authors.forename: Rohit
authors.initials: R
authors.lastname: Bhargava
mesh_terms: D000704:Analysis of Variance; D003952:Diagnostic Imaging; D006801:Humans; D008962:Models, Theoretical; D012107:Research Design; D017550:Spectroscopy, Fourier Transform Infrared; D046888:Tissue Array Analysis