Participants rated three items from the Minnesota Nicotine Withdrawal Scale from 1 (none) to 5 (severe) (Etter & Hughes, 2006; Hughes & Hatsukami, 1986). Specific items were “irritability/frustration,” “difficulty concentrating,” and “impatience” and their factor loadings were 0.90, 0.81 and 0.89 respectively. Participants also rated four items taken from the Profile of Mood States (POMS) on a scale of 1 (not at all) to 5 (extremely) (McNair, Lorr, & Droppleman, 1971). The POMS Negative Affect items were downhearted (loading = 0.69), discouraged (loading = 0.76), uneasy (loading = 0.73), and anxious (loading = 0.79). Sum scores from the three withdrawal questions and four POMS Negative Affect items were correlated 0.79 and were thus summed to produce a single withdrawal/NA scale (Piasecki, Kenford, Smith, Fiore, & Baker, 1997).
