Estimating the Reliability of Emotion Measures over Very Short Intervals: The Utility of Within- Session Retest Correlations

Short measures are commonly used when conducting research involving emotions. However,obtaining appropriate estimates of reliability for short measures is traditionally problematic andis a reoccurring concern in emotion research. To address this issue, we compare the withinsessiontest-retest and factor analysis methods for estimating the reliability of items in thePANAS-X. Results indicate that within-session test-retest (𝑟𝑋(𝑑)) estimates outperform the factoranalysis method by demonstrating stronger relationships with item properties relevant toreliability and validity-related criteria. In addition, 𝑟𝑋(𝑑) estimates appropriately generalizeacross samples with various instruction stems and prevent corrections for attenuation greater than1.00. Therefore, we encourage researchers to use the corresponding average item-level 𝑟𝑋(𝑑)estimates reported here to correct for attenuation when examining single-items from the PANASXif a test-retest design is not feasible.