Studies of test score comparability have been conducted at different stages in the history of testing to ensure that test results carry the same meaning regardless of test conditions. The expansion of at-home testing via remote proctoring sparked another round of interest. This study uses data from three licensure tests to assess potential mode effects associated with the dual option of on-site testing at test centers and at-home testing via remote proctoring. We generated propensity score weights to balance the two self-selected groups in order to detect the mode effect on the test outcomes. We also assessed the potential impact of omitted variables on the estimated mode effect. Results of the study indicate that the demographic compositions of the test takers are similar before and after the introduction of the RP option. Examinees under the two testing modes differ slightly on certain background variables. Once the group differences are adjusted by propensity score weighting, the estimated mode effects are small and nonsystematic across test titles overall. We note some variations across subgroups based on gender and race.