Challenges and opportunities in clinical field research: A Bourdieusian analysis of Fiocruz's experience in Brazil.

To identify and analyze the main challenges and opportunities of clinical field research from the perspective of Pierre Bourdieu's reflexive sociology, using the experiences of the Fiocruz Clinical Research Platform in Brazil as a case study. A convergent mixed-methods study with a cross-sectional design was conducted involving 51 research team members linked to Fiocruz calls for proposals. Quantitative data were analyzed using descriptive statistics. Qualitative data underwent thematic analysis supported by MAXQDA, grounded in the analytical categories of field, habitus, and capital. The sample comprised predominantly women (76.5%) and highly qualified professionals with graduate degrees (80.4%). Logistical challenges were almost ubiquitous (96.1%), with access to remote locations being the most frequently cited barrier (82.4%), highlighting geographic isolation as a major constraint on knowledge production. Ethical challenges were reported by 52.9% of the agents, with obtaining the Informed Consent Form or Assent Form being the most frequent barrier (35.3%). This challenge was largely driven by participants' comprehension difficulties (61.1%), misinformation (55.6%), and mistrust (50.0%). Notably, the study revealed an engagement paradox: although 90.2% of researchers perceived direct impact on the community as a significant opportunity, inclusive practices remained scarce. Specifically, 80.4% did not consult local leaders, and 88.2% did not integrate community residents into the field teams. The logistical and ethical barriers reflect structural vulnerabilities and capital asymmetries in the scientific field, where the researcher's symbolic authority often legitimizes social distance from the territory. Consolidating clinical field research as a driver of equity within the Unified Health System (SUS) depends on the institutional capacity to convert scientific capital into social capital. It is imperative to transcend technocratic perspectives by institutionalizing operational risk management and strengthening symmetrical dialogues that recognize communities as subjects with legitimate cultural capital.