Compara mètodes

	Disseny de quatre grups de Solomon	Disseny experimental pretest-posttest
Camp	Disseny experimental	Disseny experimental
Família	Process / pipeline	Process / pipeline
Any d'origen	1949	1963 (formalized in Campbell & Stanley)
Autor original	Richard L. Solomon	Donald T. Campbell and Julian C. Stanley
Tipus	True experimental design	Experimental / quasi-experimental research design
Font seminal	Solomon, R. L. (1949). An extension of control group design. Psychological Bulletin, 46(2), 137–150.	Campbell, D. T., & Stanley, J. C. (1963). Experimental and Quasi-Experimental Designs for Research. Rand McNally.
Àlies	Solomon design, four-group design, Solomon four-group control design, S4GD	pretest-posttest design, before-after design, pre-post design, two-wave experimental design
Relacionats	5	5
Resum	The Solomon Four-Group Design extends the classic pretest-posttest control-group design by adding two groups that receive no pretest, enabling researchers to detect whether the pretest itself alters participants' responses to the treatment. Introduced by Richard L. Solomon in 1949, it remains the gold standard for isolating the independent effect of a pretest and for obtaining unbiased estimates of treatment efficacy.	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.