Objective: To evaluate the effectiveness of 2 interventions, including the DrugFactsBox format for presenting written medication information and the SMART (Strategic Memory Advanced Reasoning Training) program designed to enhance gist (i.e., “bottom-line” meaning) reasoning ability. Methods: We used a 2 × 2 factorial research design. A total of 286 patients with rheumatoid arthritis were randomly assigned to 1 of 4 groups, including DrugFactsBox with the SMART program, DrugFactsBox without the SMART program, other consumer medication information (CMI) with the SMART program, and other CMI without the SMART program. Data were collected via telephone interviews and online questionnaires at 4 time points, including baseline and 6-week, 3-month, and 6-month time points following baseline. The primary outcome variable was informed decision-making, which was defined as making a value-consistent decision concerning use of disease-modifying antirheumatic drugs based on adequate knowledge. Results: We found no main effects for the 2 interventions, either alone or in combination. However, there was a significant interaction between assignment to the SMART/no SMART groups and informed decision-making at baseline. Among participants in the SMART groups who did not meet the criteria for informed decision-making at baseline, 42.5% met the criteria at the 6-month follow-up, compared to 23.6% of participants in the no SMART groups (mean difference 18.9 [95% confidence interval 5.6, 32.2]; P = 0.007). This difference was driven by increased knowledge in the SMART groups. Among participants who met the criteria for informed decision-making at baseline, the difference between the SMART and no SMART groups was not statistically significant. Conclusion: Participation in a theory-driven program to enhance gist reasoning may have a beneficial effect on informed decision-making among patients with inadequate knowledge concerning therapeutic options.