title: Determination of minimum sample size and discriminatory expression patterns in microarray data.
abstract: BACKGROUND
  Transcriptional profiling using microarrays can reveal important information about cellular and tissue expression phenotypes, but these measurements are costly and time consuming. Additionally, tissue sample availability poses further constraints on the number of arrays that can be analyzed in connection with a particular disease or state of interest. It is therefore important to provide a method for the determination of the minimum number of microarrays required to separate, with statistical reliability, distinct disease states or other physiological differences.
  
  
  RESULTS
  Power analysis was applied to estimate the minimum sample size required for two-class and multi-class discrimination. The power analysis algorithm calculates the appropriate sample size for discrimination of phenotypic subtypes in a reduced dimensional space obtained by Fisher discriminant analysis (FDA). This approach was tested by applying the algorithm to existing data sets for estimation of the minimum sample size required for drawing certain conclusions on multi-class distinction with statistical reliability. It was confirmed that when the minimum number of samples estimated from power analysis is used, group means in the FDA discrimination space are statistically different.
  
  
  BACKGROUND
  gregstep@mit.edu
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Daehee
authors.initials: D
authors.lastname: Hwang
authors.forename: William A
authors.initials: WA
authors.lastname: Schmitt
authors.forename: George
authors.initials: G
authors.lastname: Stephanopoulos
authors.forename: Gregory
authors.initials: G
authors.lastname: Stephanopoulos
mesh_terms: D000208:Acute Disease; D000465:Algorithms; D030561:Databases, Nucleic Acid; D016002:Discriminant Analysis; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D007951:Leukemia, Myeloid / Q000145:classification / Q000235:genetics; D008957:Models, Genetic; D015233:Models, Statistical; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000145:classification / Q000235:genetics; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018401:Sample Size; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000379:methods*; D013269:Stochastic Processes