Chunk #12 — MATERIALS AND METHODS — Analytic Strategy

Source

Associations of alcohol, nicotine, cannabis, and drug use/dependence with educational attainment: evidence from cotwin-control analyses.

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yes

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Data preparation and preliminary analyses were conducted using SAS (SAS Institute, Inc., 1999–2001). Logistic and conditional logistic regression analyses were conducted using STATA (StataCorp, 2005), which uses a robust variance estimator to adjust for the non-independence of data from twins (used in the logistic regression analyses).