title: Alcohol use from adolescence through early adulthood: an assessment of measurement invariance by age and gender.
abstract: OBJECTIVE
  Studies on alcohol use and related constructs rarely test for measurement invariance to assess the reliability and validity of measures of alcohol use across different subpopulations of interest or ages. This failure to consider measurement invariance may result in biased parameter estimates and inferences. This study aimed to test measurement invariance of alcohol use across gender and age using a US nationally representative sample to inform future longitudinal studies assessing alcohol use.
  
  
  METHODS
  The National Longitudinal Study of Adolescent to Adult Health, a school-based, nationally representative longitudinal study conducted in 1994-95, 2001-02 and 2008.
  
  
  METHODS
  All regions within the United States; participants were selected via a clustered sample design from 80 high schools that represented the national population.
  
  
  METHODS
  Youth and young adults aged 13-31 years who had valid data on all three alcohol items within wave: 18 923 from wave 1; 14 315 from wave 3; and 14 785 from wave 4.
  
  
  METHODS
  Alcohol use measurement models were constructed using past-year general drinking frequency, heavy episodic drinking frequency and average quantity when drinking. Configural (factor structure), metric (factor loadings) and scalar (item intercepts) measurement invariance models were tested by gender and for each year of age from 13 to 31 years.
  
  
  RESULTS
  All models passed the threshold for configural invariance. Comparisons between males and females demonstrated metric (and usually scalar) non-invariance for most ages beyond middle adolescence. Nearly all 1- and 2-year contrasts passed metric invariance. Scalar non-invariance was most prevalent in age comparisons between late adolescence and early adulthood, particularly for tests using 2-year age increments.
  
  
  CONCLUSIONS
  Studies that do not account for the effects of gender and age on the measurement of alcohol use may be statistically biased.
authors.affiliation: Population Research Center, University of Texas at Austin, Austin, TX, USA.
authors.forename: Jessica N
authors.initials: JN
authors.lastname: Fish
authors.affiliation: Norton School of Family and Consumer Sciences, The University of Arizona, Tucson, AZ, USA.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Pollitt
authors.affiliation: Institute for Social Research and Department of Psychology, University of Michigan, Ann Arbor, MI, USA.
authors.forename: John E
authors.initials: JE
authors.lastname: Schulenberg
authors.affiliation: Human Development and Family Sciences, University of Texas at Austin, Austin, TX, USA.
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Russell
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000428:Alcohol Drinking / Q000453:epidemiology*; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011594:Psychometrics; D015203:Reproducibility of Results; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D000066608:Underage Drinking / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: Alcohol use; development; latent variable modeling; longitudinal; measurement invariance; methods