Patterns of Nonresponse for Key Questions in NSDUH and Implications for Imputation

• Activity Number: 152
• Type: Contributed
• Date/Time: Monday, July 30, 2007 : 10:30 AM to 12:20 PM
• Sponsor: Section on Survey Research Methods
• Author(s): Peter Frechtel*+ and Elizabeth Copello
• Companies: RTI International and RTI International
• Keywords: imputation ; nonresponse ; nonresponse bias ; probes ; item nonresponse

Abstract

The National Survey on Drug Use and Health (NSDUH), an annual nationwide survey involving approximately 67,500 subjects per year, does not make use of callbacks. However, for several key questions on drug use in the NSDUH, follow-up questions, or "probes," are presented to subjects who entered a response of "don't know" or "refused" to the original questions. The probes are a low-cost method of increasing item response rates, and of reducing nonresponse bias. An earlier study examined the success of the probes in increasing item response rates. This paper will mainly focus on nonresponse bias. There is strong evidence that respondents who answered the probes differ from respondents who answered the original questions, especially those who refused to answer the original questions. Some improvements to the current imputation method are proposed and evaluated.