observational study
estudio observacional
a study in which researchers record what already happens, without assigning treatments to anyone.
Example
Surveying 1,000 adults about how much coffee they drink and how well they sleep is an observational study.
In Spanish
estudio observacional — un estudio en el que los investigadores registran lo que ya pasa, sin asignar tratamientos a nadie.
Encuestar a 1,000 adultos sobre cuánto café toman y qué tan bien duermen es un estudio observacional.