Co-creation with women with breast cancer, their families, and healthcare professionals of a MOOC aimed at women with breast cancer; and evaluation of the MOOC's effectiveness and acceptability.

1. MOOC co-creation: development of a MOOC initially structured into modules consisting of a variety of downloadable educational resources such as videos, audios, infographics, texts, etc., covering several units related to Person-Centered Care (Shared Decision-Making, strategies for managing the clinical encounter, Patient Decision Aids, etc.) and Digital Health Literacy (skills, tools, etc.). These resources will serve as the central focus of the educational intervention, and may undergo appropriate adjustments established during the co-creation sessions.
2. MOOC acceptability and effectiveness: evaluation of the MOOC in terms of effectiveness (level of Health Literacy, Digital Health Literacy, and knowledge acquired) and acceptability (usability, areas for improvement, etc.)

Digital Health Literacy through the eHealth Literacy Scale (eHEALS). It is an 8-item scale that uses a 5-point Likert scale to answer each question with response options ranging from "strongly agree" to "strongly disagree", resulting in a total score ranging from 8 to 40.

Health Literacy through the Health Literacy Survey European Questionnaire-16 items (HLS-EU-Q16). It is an abbreviated version of the Health Literacy Survey European Questionnaire (HLS-EU-Q) and consists of 16 items, with each question answered by choosing one response from the options: 'very difficult', 'fairly difficult', 'fairly easy', and 'very easy' giving a total score from 16 to 64.

Knowledge acquired before study each unit of the MOOC using a scale designed specifically for the study and in accordance with the content of each unit

Acceptability (usability, areas for improvement, etc.) of the MOOC using a scale designed specifically for the study, adhering to the methodology of the technology acceptance model (TAM)