قارن الطرق

	تصميم تجريبي محظور بقياس قبلي وبعدي	تصميم التجربة بالقياس القبلي والبعدي
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1935 (blocking, Fisher); 1963 (pretest-posttest + blocking synthesis, Campbell & Stanley)	1963 (formalized in Campbell & Stanley)
صاحب الطريقة	Donald T. Campbell & Julian C. Stanley (systematized); blocking technique from Ronald A. Fisher	Donald T. Campbell and Julian C. Stanley
النوع	Experimental design	Experimental / quasi-experimental research design
المصدر التأسيسي	Campbell, D. T., & Stanley, J. C. (1963). Experimental and Quasi-Experimental Designs for Research. Rand McNally.	Campbell, D. T., & Stanley, J. C. (1963). Experimental and Quasi-Experimental Designs for Research. Rand McNally.
الأسماء البديلة	blocked pre-post design, RBPP design, block-randomized pretest-posttest design, randomized block pre-post control group design	pretest-posttest design, before-after design, pre-post design, two-wave experimental design
ذات صلة	6	5
الملخص	The blocked pretest-posttest experimental design combines blocking — grouping participants into homogeneous strata before randomization — with pre- and post-intervention measurement. Blocking controls for known sources of variability (e.g., baseline ability, gender, site), while the pretest-posttest structure quantifies change scores directly. Together, they reduce error variance and increase statistical power compared to a simple pretest-posttest design, making this approach well suited to educational, clinical, and behavioral intervention studies.	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.