In conclusion, substantive and psychometric considerations strongly support four new criteria for further testing and potential inclusion in the DSM-5. These criteria concern smoking heaviness, latency to smoke upon awakening, craving to smoke, and withdrawal severity. Other criteria were identified for additional research and possible inclusion. Little evidence supported the inclusion of most existing DSM-IV items, but rewording and reformulation might improve their validities. This work also nominated important outcomes for the evaluation of TD criteria or items, and suggested important topics or guiding principles to advance the assessment of TD: e.g., regarding the difficulty level of the assessment (the severity of use that warrants diagnosis), and whether the assessment should be specific to tobacco dependence versus applicable to any substance use disorder. The strongest recommendation is that the development of DSM-5 be driven by systematic, psychometric evaluation with regards to theoretically and clinically meaningful criteria. The DSM-IV has face validity because it directly assesses occurrence of harm as a function of tobacco use; this virtue is outweighed by its poor predictive validity. More research is clearly needed on this important topic.
