השוואת שיטות

	מבנה ניסויי אקראי מבוקר וכפול-סמיות	מערך ניסויי של מבחן קדם ומבחן עוקב
תחום	תכנון ניסויים	תכנון ניסויים
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1930s–1950s (formalized in clinical trial methodology)	1963 (formalized in Campbell & Stanley)
הוגה השיטה	R. A. Fisher (experimental control foundations); blinding practices evolved in clinical research through the 20th century	Donald T. Campbell and Julian C. Stanley
סוג	Experimental research design	Experimental / quasi-experimental research design
מקור מכונן	Fisher, R. A. (1935). The Design of Experiments. Oliver and Boyd.	Campbell, D. T., & Stanley, J. C. (1963). Experimental and Quasi-Experimental Designs for Research. Rand McNally.
כינויים	double-blind controlled experiment, DB-CG design, double-masked controlled trial, double-blind controlled study	pretest-posttest design, before-after design, pre-post design, two-wave experimental design
קשורות	5	5
תקציר	A double-blind control group experimental design is a rigorous experimental structure in which participants are randomly assigned to at least one treatment group and one control group, while both the participants and the researchers collecting or assessing outcomes are kept unaware of group assignment. By combining allocation concealment with blinding at two levels, the design minimizes expectancy bias, placebo effects, and assessor bias simultaneously, making it a cornerstone of high-quality intervention research in medicine, psychology, and the social sciences.	The pretest-posttest experimental design measures participants on the outcome variable before and after treatment, typically with random assignment to treatment and control groups. The difference between pre- and post-scores isolates the treatment effect from baseline variation, making this one of the most widely used frameworks in experimental and quasi-experimental research across education, psychology, medicine, and the social sciences.