This dissertation focuses on factors of multimedia job aids that modify workload, protocol adherence and clinical errors in community health workers. Literature show that community health workers performance is not acceptable even with support of paper job aids. There are cognitive theories that try to explain reasons why the performance of community health workers is poor regardless of the access to paper based-job aid. Based on cognitive sciences and multimedia design theories an intervention was designed to compare alternative representations for the information contained on paper job aids and the capability of this designed aids to enhance community health workers performance. The dissertation is divided in 5 main parts: 1. identification and description of the problem, 2. a methodological approach to create and evaluate an intervention, 3. Presentation of results of the intervention evaluation, 4. Discussion of findings, and 5. Conclusions.