Secondary analysis of an RCT on Emergency Department-Initiated Tobacco Control: Repeatedly assessed point-prevalence abstinence up to 12 months and extension of results through a 10-year follow-up.

INTRODUCTION:Emergency departments (EDs) are opportune places for tobacco control interventions. The 'Tobacco Control in an Urban Emergency Department' (TED) study, ISRCTN41527831, originally evaluated the effect of motivational interviewing on-site plus up to four booster telephone calls on 12-month abstinence. This study's aim was to evaluate the effect of the intervention on 7-day point-prevalence abstinence at 10 years follow-up (primary outcome) as well as on repeated point-prevalence abstinence at 1, 3, 6, 12 months and at 10 years (continual smoking abstinence, secondary outcome). METHODS:At the 10 years follow-up and after informed consent, study participants responded to a mailed questionnaire. The primary outcome was analyzed in observed-only and in all-cases analyses. The secondary outcomes were analyzed using a multiple adjusted GLMM for binary outcomes. RESULTS:Out of 1012 TED-study participants, 986 (97.4%) were alive and 231 (23.4% of 986) responded to the follow-up at 10 years. For observed-only and all-cases analyses, the effect of the baseline intervention on 7-day point-prevalence abstinence at the 10 years follow-up was statistically non-significant. However, when taking into account all repeated measures, the intervention significantly influenced continual abstinence with odds ratio 1.32 (95% CI: 1.01-1.73; p=0.042). Baseline motivation, perceived self-efficacy to stop smoking, and nicotine dependency were independently associated with long-term continual smoking abstinence (all p<0.05). CONCLUSIONS:A conventional analysis failed to confirm a significant effect of the ED-initiated tobacco control intervention on the point-prevalence abstinence at 10 years. Results from a more integrative analysis nonetheless indicated an enduring intervention effect on continual abstinence among smokers first encountered in the emergency department setting 10 years earlier

Simplification of Reversible Markov Chains by Removal of States With Low Equilibrium Occupancy

We present a practical method for simplifying Markov chains on a potentially large state space when detailed balance holds. A simple and transparent technique is introduced to remove states with low equilibrium occupancy. The resulting system has fewer parameters. The resulting effective rates between the remaining nodes give dynamics identical to the original system’s except on very fast timescales. This procedure amounts to using separation of timescales to neglect small capacitance nodes in a network of resistors and capacitors. We illustrate the technique by simplifying various reaction networks, including transforming an acyclic four-node network to a three-node cyclic network. For a reaction step in which a ligand binds, the law of mass action implies a forward rate proportional to ligand concentration. The effective rates in the simplified network are found to be rational functions of ligand concentratio

Comparative analysis of hepatitis C virus phylogenies from coding and non-coding regions: the 5' untranslated region (UTR) fails to classify subtypes

BACKGROUND: The duration of treatment for HCV infection is partly indicated by the genotype of the virus. For studies of disease transmission, vaccine design, and surveillance for novel variants, subtype-level classification is also needed. This study used the Shimodaira-Hasegawa test and related statistical techniques to compare phylogenetic trees obtained from coding and non-coding regions of a whole-genome alignment for the reliability of subtyping in different regions. RESULTS: Different regions of the HCV genome yield inconsistent phylogenies, which can lead to erroneous conclusions about classification of a given infection. In particular, the highly conserved 5' untranslated region (UTR) yields phylogenetic trees with topologies that differ from the HCV polyprotein and complete genome phylogenies. Phylogenetic trees from the NS5B gene reliably cluster related subtypes, and yield topologies consistent with those of the whole genome and polyprotein. CONCLUSION: These results extend those from previous studies and indicate that, unlike the NS5B gene, the 5' UTR contains insufficient variation to resolve HCV classifications to the level of viral subtype, and fails to distinguish genotypes reliably. Use of the 5' UTR for clinical tests to characterize HCV infection should be replaced by a subtype-informative test

Modern and Classical Languages

This departmental history was written on the occasion of the UND Centennial in 1983.https://commons.und.edu/departmental-histories/1042/thumbnail.jp