In epidemiology and statistics, an observational study draws inferences about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator. This is in contrast with experiments, such as randomized controlled trials, where each subject is randomly assigned to a treated group or a control group before the start of the treatment.
Read more about Observational Study: Reasons For Uncontrolled Experimentation, Degree of Usefulness and Reliability, Discussion
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“Many people operate under the assumption that since parenting is a natural adult function, we should instinctively know how to do it—and do it well. The truth is, effective parenting requires study and practice like any other skilled profession. Who would even consider turning an untrained surgeon loose in an operating room? Yet we “operate” on our children every day.”
—Louise Hart (20th century)