Buit-in Timer (IMAGE) American Chemical Society Caption Paper-based diagnostic tests could become more accurate with a built-in timer that uses a color change signal (red dot at lower left) to indicate when test results are ready for analysis. Credit Scott T. Phillips Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.