قارن الطرق

	تصميم تجريبي محظور بقياس قبلي وبعدي	تصميم التجربة بالمجموعة الضابطة
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1935 (blocking, Fisher); 1963 (pretest-posttest + blocking synthesis, Campbell & Stanley)	1935 (Fisher); 1963 (Campbell & Stanley codification)
صاحب الطريقة	Donald T. Campbell & Julian C. Stanley (systematized); blocking technique from Ronald A. Fisher	Ronald A. Fisher; systematised by Donald T. Campbell & Julian C. Stanley
النوع	Experimental design	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	controlled experiment, true experimental design, randomized controlled design, treatment-control design
ذات صلة	6	4
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.	Control group experimental design is a fundamental experimental structure in which participants are assigned to at least two groups — a treatment group that receives the intervention and a control group that does not — so that the effect of the intervention can be isolated by comparing outcomes across groups. Randomisation of assignment strengthens causal inference by balancing known and unknown confounders.