Increasing Response Rates and the Consequences in the Dutch Parliamentary Election Study 2006

This article deals with specific measures to enhance response rates in the Dutch Parliamentary Election Study (DPES) conducted around the elections on November 22, 2006. It demonstrates that a specific fieldwork strategy, including new advance letters, incentives, interviewer training sessions, and a reapproach of noncontacts and refusals, resulted in a response rate of 72% (first wave) and 64% (second wave). Moreover, the distributions of party choice in the DPES fit perfectly with the official election results. However, the 93.1% reported turnout is substantially higher than the official 80.1% turnout figure. Five percent of the 13% gap in reported and official turnout in the DPES is assigned to stimulus effects and the remaining 8% to a mixture of nonresponse bias and social desirability effects.