The article reports on an assessment of the effectiveness of the MLA Research Training Institute (RTI) for the years 2018 and 2019. The RTI is a year-long continuing education research methods training and support program for health sciences librarians. The study focuses on assessing RTI participants' research confidence after program completion and compares these results with their perceptions of workshop/program performance and learning outcomes. In addition, the authors discuss how the findings were applied to inform and improve the program. The study used a 26-item questionnaire, RTI Research Confidence Questionnaire, to gather information on participants' self-reported research confidence before the workshop, immediately after the workshop, and one year after the workshop to determine statistically significant differences. Differences in research confidence were identified by using three nonparametric statistical tests. Additional workshop and program surveys were used to corroborate the research confidence findings. Post-workshop and one-year-after-workshop research confidence ratings were significantly higher than pre-workshop levels for years 1 and 2. A comparison of median ratings between years 1 and 2 showed significant increases in research confidence for nine items in year 2. Participants' positive perceptions of workshop/program effectiveness and learning outcomes corroborated these findings. Overall assessment findings indicated that RTI training helped participants understand, use, and apply research skills to conduct research. Findings also revealed that participants' heightened research confidence persisted at least 12 months postintervention. The RTI Research Confidence Questionnaire proved effective for rigorously assessing and improving the RTI program. This study enhances the currently limited evidence on evidence-based approaches for assessing and improving research instruction for librarians.