The 2008 Quick-Service Drive-Thru Performance Study was produced and conducted by Insula Research.

The primary objective of this annual study is to rank the leading* quick-service restaurant chains in several categories of drive-thru operations. Categories measured in the study include: wait time, service time, order accuracy, suggestive-sell incidence, exterior appearance assessment, speaker clarity, menuboard appearance, availability of electronic payment options, and order-confirmation boards. Overall composite score rankings are based on each chain’s performance in the categories of service speed, order accuracy, menuboard appearance, and speaker clarity.

Data was collected during April, May, June, and July 2008. Restaurants were visited between the lunch hours of 11 a.m. and 2:30 p.m., and between the dinner hours of 4 p.m. and 7 p.m. Each location was visited a maximum of twice—once during the lunch period and once during the dinner period. A total of 11,519 service times were collected, and a total of 5,821 orders were reviewed for accuracy. The 2008 study includes assessments from 25 quick-service restaurant chains. Information was collected in all 50 states.

The sample size selected for each chain was based on the total number of drive-thru units each chain operates. Analysis was performed to set sample sizes that resulted in approximately the same margin of error for each chain included in the study. For this study the maximum error (i.e. worst-case scenario) at a 95 percent confidence level was targeted at approximately 5.7 percent in a two-way split of the data.