Quality Assurance and Interval Estimation Procedures for Road Condition Distress Scores

This report describes the statistical analysis of the Texas Department of Transportation (TxDOT) Pavement Management Information System (PMIS) distress data and audit procedures used to verify satisfactory performance of statewide distress surveys. Several improvements are provided, including a method of determining the sample size that is much more rigorous than the current fixed percentage method. In addition, a review of the confidence interval for the average condition of all pavements in Texas has been conducted.