Prior research highlights the benefits of multimode surveys and best practices for item-by-item (IBI) and matrix-type survey items. Some researchers have explored whether mode differences for online and paper surveys persist for these survey item types. However, no studies discuss measurement invariance when both item types and online modes are used in the same study. This study uses a two-way repeated-measures design to explore whether matrix and IBI-type items can be compared across online and paper survey modes. Personality data for extraversion and conscientiousness traits yielded from four survey conditions are used in this study: 1) paper mode, IBI-type items, 2) paper mode, matrix-type items, 3) online mode, IBI-type items, and 4) online mode, matrix-type items. A 2-parameter graded response model (GRM) using marginal maximum likelihood (MML) with the Gauss-Hermite quadrature rule for integral approximations was used to estimate item parameters. Analysis of item characteristic curves (ICCs) and item information curves (IICs) showed small differences in a[subscript i] and b[subscript i] parameters where the IBI paper format yielded a higher probability of endorsing more extreme responses at lower levels of conscientiousness compared to online matrix-type items. However, study results showed high internal consistency as measured by coefficient alpha values, no evidence of straightlining for any condition, and no evidence of differential item functioning (DIF) explored with an ordinal logistic regression for any items across conditions. These findings provide evidence of measurement invariance for comparisons of 5-point Likert-type, IBI and matrix-type items shown in groups of five across online and paper modes. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]