MULTILEVEL COVARIANCE STRUCTURE-ANALYSIS OF SIBLING SUBSTANCE USE ANDINTRAFAMILY CONFLICT

Conventional covariance structure analysis, such as factor analysis, i s often applied to data that are obtained in a hierarchical fashion su ch as siblings observed within families. A more appropriate specificat ion is demonstrated which explicitly models the within-level and betwe en-level covariance matrices of sibling substance use and intrafamily conflict. Participants were 267 target adolescents (mean age = 13.11 y ears) and 318 siblings (mean age = 15.03 years). The level of homogene ity within sibling clusters, and heterogeneity among families, was suf ficient to conduct a multilevel covariance structure analysis (MCA). P arental and family-level variables consisting of marital status, socio economic status, marital discord, parent use, and modeling of substanc es were used to explain heterogeneity among families. Marital discord predicted intrafamily conflict, and parent marital status and modeling of substances predicted sibling substance use. Advantages and uses of hierarchical designs and conventional covariance structure software f or multilevel data are discussed.