قارن الطرق

	تصميم تجريبي متقاطع قبلي-بعدي	تصميم التجربة بالقياس القبلي والبعدي
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1963 (Campbell & Stanley framework); crossover methodology formalized 1980s–2000s	1963 (formalized in Campbell & Stanley)
صاحب الطريقة	Donald T. Campbell & Julian C. Stanley (pretest-posttest framework); Stephen Senn (crossover trial methodology)	Donald T. Campbell and Julian C. Stanley
النوع	Within-subjects experimental design	Experimental / quasi-experimental research design
المصدر التأسيسي	Senn, S. (2002). Cross-over Trials in Clinical Research (2nd ed.). Wiley. ISBN: 978-0471496533	Campbell, D. T., & Stanley, J. C. (1963). Experimental and Quasi-Experimental Designs for Research. Rand McNally.
الأسماء البديلة	within-subjects pretest-posttest design, repeated-measures crossover design, AB/BA pretest-posttest design, crossover repeated-measures design	pretest-posttest design, before-after design, pre-post design, two-wave experimental design
ذات صلة	5	5
الملخص	A crossover pretest-posttest experimental design is a within-subjects experiment in which each participant receives two or more treatments in a randomized sequence, with outcome measurements taken both before and after each treatment period. By serving as their own control across conditions, participants allow direct intra-individual comparison, dramatically increasing statistical power while reducing the sample size required relative to a parallel-group design.	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.