Effects of measurement methods on the relationship between smoking and delay reward discounting
Article first published online: 23 JAN 2012
© 2011 The Authors, Addiction © 2011 Society for the Study of Addiction
Volume 107, Issue 5, pages 1003–1012, May 2012
How to Cite
Stillwell, D. J. and Tunney, R. J. (2012), Effects of measurement methods on the relationship between smoking and delay reward discounting. Addiction, 107: 1003–1012. doi: 10.1111/j.1360-0443.2011.03742.x
- Issue published online: 4 APR 2012
- Article first published online: 23 JAN 2012
- Accepted manuscript online: 30 NOV 2011 05:50AM EST
- Submitted 31 July 2011; initial review completed 30 September 2011; final version accepted 25 November 2011
- Delay discounting;
- exponential discounting;
- hyperbolic discounting;
- magnitude effect;
- online social networks;
Aims Delay reward discounting (DRD) measures the degree to which a person prefers smaller rewards soon or larger rewards later. People who smoke have been shown to have higher DRD. There are several ways of measuring DRD, and the method used might influence the association between smoking and DRD. The key differences are the order in which the items are presented, the delays used and the magnitude of the delayed amount.
Setting An international online study running from September 2010 to June 2011.
Participants A total of 9454 individuals; 38% male, mean age = 23.1 years.
Design and measurements Users completed a multi-item DRD task. They were randomly presented the immediate rewards in an ascending, descending or randomized order. The delays were between 1 week and 5 years. The delayed amounts were $1000 for all delays, and $100 for 1 month. Users also self-reported their smoking status.
Findings A hyperbolic DRD function fitted better than an exponential function. There were differences in the derived DRD function based on methodology used; items presented in a randomized order, longer delays and smaller rewards showed steeper discounting. However, these did not interact with smoking status, as for all methodologies used daily smokers showed the steepest discounting, followed by non-daily smokers, then non-smokers.
Conclusions Smokers discount future consequences more than non-smokers, irrespective of which measurement is used, but variations in method lead to different estimates that are not comparable between experiments.