General aspects of the use of mixed methods for health research.

Traditionally, research has been divided according to its methodology into quantitative and qualitative. Mixed research methodology combines both methods and has established itself as a third approach, allowing to comprehensively address high-complexity research problems. Although there are various definitions of mixed methods research, they all share aspects such as the collection and analysis of both quantitative and qualitative data and the integrated interpretation of the results within the same research. This type of research is an important tool to address the complexity of health sciences, allowing the understanding and integration of quantitative data with experience-based aspects. In this way, a broad and deep perspective of health problems is achieved, providing a solution to sanitary policies and services. During the development of mixed methods research, there are key stages where both approaches can be integrated depending on the objectives set by the investigators. Although mixed methods studies may differ widely, general models have been identified to guide the development of a single specific design. These models are classified according to the priority of each approach, the sequence in which each approach will be executed, the level and timing of data integration, and the purpose of integrating the data for the study.