Callers agreeing to participate in new the study were contacted by project staff within 1 week of their initial call to the CIS to complete a verbal, audiotaped informed consent, and a baseline assessment. Follow-up assessment calls were conducted 5 and 12 weeks after the baseline assessment. Participants were randomly assigned to receive one of two telephone-based counseling protocols as part of the clinical trial (standard vs. enhanced). Standard counseling consisted of the single CIS counseling session that had been delivered during the initial call to the CIS, plus an offer of Spanish-language self-help materials that would be mailed to the participant if preferred. The content of counseling, session length, and treatment duration were based on evidence presented in the U.S.

Public Health Service’s Treating Tobacco Use and Dependence Clinical Practice Guideline (Fiore et al., 2000). Enhanced counseling consisted of the original CIS call and three additional calls scheduled through postquit week 4, which incorporated motivational enhancement techniques (Miller & Rollnick, 2002) into the guideline-based approach (Fiore et al., 2000). Assessment and counseling calls were conducted in Spanish. Detailed information about the treatment protocol and outcome is available elsewhere (Wetter et al., 2007). Measures and variables of interest Smoking level. Smoking level was assessed at baseline and defined by self-reported cigarettes smoked per day. Smoking level classification was informed by S. H. Zhu et al. (2007): low-level (1�C5 cigarettes/day), light (6�C10 cigarettes/day), and moderate/heavy smokers (��11 cigarettes/day).

The separation of low-level and light smokers allowed for a detailed examination of potential differences in withdrawal, dependence, and abstinence among this particularly understudied end of the smoking-level spectrum. Demographic variables. Demographic measures collected at baseline included age, gender, educational achievement, marital status, annual household income, ethnicity, time in the United States, and language spoken at home. Several variables were dichotomized: marital status (married vs. not married), household income (��US$20,000 vs. >$20,000), ethnicity (Mexican vs. other), time in the United States (��10 years or >10 years), and language spoken at home (only Spanish vs. not only Spanish). Tobacco dependence.

Tobacco dependence was measured at baseline with the Wisconsin Inventory of Smoking Dependence Motives (WISDM-68; Piper et al., 2004) and with single-item dependence variables (i.e., number of years smoked and dichotomized time to first cigarette of the day [��5 min or >5 min GSK-3 after waking]). The WISDM-68 is a comprehensive, multidimensional measure of dependence that yields an overall smoking dependence score as well as subscale scores for critical dimensions of dependence, including nonphysical indices of dependence (e.g., affiliative attachment, automaticity, and social/environmental goads; Piper et al.