So sánh phương pháp

	Thiết kế Solomon bốn nhóm có khối	Thiết kế thực nghiệm đo lường trước và sau can thiệp
Lĩnh vực	Thiết kế thí nghiệm	Thiết kế thí nghiệm
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1949 (base); blocking extension applied in behavioral and social sciences from mid-20th century onward	1963 (formalized in Campbell & Stanley)
Người khởi xướng	Richard L. Solomon (base design, 1949); blocking integrated from classical experimental design tradition (Fisher, 1935)	Donald T. Campbell and Julian C. Stanley
Loại	Experimental design	Experimental / quasi-experimental research design
Công trình gốc	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.
Tên gọi khác	Blocked S4G, randomized blocked Solomon design, Solomon four-group with blocking	pretest-posttest design, before-after design, pre-post design, two-wave experimental design
Liên quan	6	5
Tóm tắt	The blocked Solomon four-group design combines Solomon's classic four-group structure — which disentangles pretest sensitization effects from treatment effects — with blocking on a known nuisance variable. Participants are first grouped into homogeneous blocks (e.g., by baseline ability, gender, or site), then randomly assigned within each block to one of four conditions: pretested treatment, pretested control, unpretested treatment, and unpretested control. This structure simultaneously controls for maturation, pretest reactivity, and block-level variance, making it one of the strongest quasi-controlled experimental frameworks available.	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.