"A tutorial on count regression and zero-altered count models for longitudinal substance use data": Correction to Atkins et al. (2012).

Abstract

Reports an error in A tutorial on count regression and zero-altered count models for longitudinal substance use by David C. Atkins, Scott A. Baldwin, Cheng Zheng, Robert J. Gallop and Clayton Neighbors (Psychology of Addictive Behaviors, 2013[Mar], Vol 27[1], 166-177). The URL for the supplemental material was incorrect throughout the text due to a production error. Supplemental material for this article is available at: http://dx.doi.org/10.1037/a0029508.supp. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2012-22398-001.) Critical research questions in the study of addictive behaviors concern how these behaviors change over time: either as the result of intervention or in naturalistic settings. The combination of count outcomes that are often strongly skewed with many zeroes (e.g., days using, number of total drinks, number of drinking consequences) with repeated assessments (e.g., longitudinal follow-up after intervention or daily diary data) present challenges for data analyses. The current article provides a tutorial on methods for analyzing longitudinal substance use data, focusing on Poisson, zero-inflated, and hurdle mixed models, which are types of hierarchical or multilevel models. Two example datasets are used throughout, focusing on drinking-related consequences following an intervention and daily drinking over the past 30 days, respectively. Both datasets as well as R, SAS, Mplus, Stata, and SPSS code showing how to fit the models are available on a supplemental website. (PsycINFO Database Record (c) 2013 APA, all rights reserved). Language: en