title: Pathophysiological domains underlying the metabolic syndrome: an alternative factor analytic strategy.
abstract: OBJECTIVE
  Factor analysis (FA) has become part and parcel in metabolic syndrome (MBS) research. Both exploration- and confirmation-driven factor analyzes are rampant. However, factor analytic results on MBS differ widely. A situation that is at least in part attributable to misapplication of FA. Here, our purpose was (i) to review factor analytic efforts in the study of MBS with emphasis on misusage of the FA model and (ii) to propose an alternative factor analytic strategy.
  
  
  METHODS
  The proposed factor analytic strategy consists of four steps and confronts weaknesses in application of the FA model. At its heart lies the explicit separation of dimensionality and pattern selection and the direct evaluation of competing inequality-constrained loading patterns. A high-profile MBS data set with anthropometric measurements on overweight children and adolescents is reanalyzed using this strategy.
  
  
  RESULTS
  The reanalysis implied a more parsimonious constellation of pathophysiological domains underlying phenotypic expressions of MBS than the original analysis (and many other analyses). The results emphasize correlated factors of impaired glucose metabolism and impaired lipid metabolism.
  
  
  CONCLUSIONS
  Pathophysiological domains underlying phenotypic expressions of MBS included in the analysis are driven by multiple interrelated metabolic impairments. These findings indirectly point to the possible existence of a multifactorial etiology.
authors.affiliation: Department of Epidemiology & Biostatistics, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: cf.peeters@vumc.nl.
authors.forename: Carel F W
authors.initials: CF
authors.lastname: Peeters
authors.affiliation: Yale Center for Analytical Sciences, Yale School of Public Health, New Haven, CN.
authors.forename: James
authors.initials: J
authors.lastname: Dziura
authors.affiliation: Department of Educational Neuroscience, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Floryt
authors.initials: F
authors.lastname: van Wesel
mesh_terms: D000293:Adolescent; D000886:Anthropometry; D002648:Child; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000209:etiology; D005163:Factor Analysis, Statistical; D044882:Glucose Metabolism Disorders / Q000453:epidemiology*; D006801:Humans; D052439:Lipid Metabolism Disorders / Q000453:epidemiology*; D024821:Metabolic Syndrome / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology*; D050177:Overweight / Q000453:epidemiology*; D010641:Phenotype; D012307:Risk Factors
keywords: Factor analysis; Metabolic syndrome