The patient then waited through an extended period for healing. Then, in a surgery similar to those done to create vaginas for intersexed patients, surgeons constructed the patient's vagina by using skin grafts taken from her thighs or buttocks (Christine's vaginoplasty surgery was in 1954).
Experimental and quasi-experimental research designs. Ph.D. In an experimental design, subjects are randomly assigned to groups for different levels of treatment (or no treatment, i.e., the control group). In a quasi-experimental design, subjects are not randomly assigned to treatment; there is no randomization. Random assignments of subjects helps control for participant differences, one of the main sources of threats to internal validity of a research study.
Quasi-experimental designs do not rely on random assignment when placing participants into experimental groups. Quasi-experimental designs are used when the independent variable is such that random assignment cannot be used because it is related to some innate quality, such as race or gender.