قارن الطرق

	تصميم سولومون الرباعي المجموعات المحظور	التجارب العشوائية المنظمة (Blocked Randomized Controlled Trial)
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1949 (base); blocking extension applied in behavioral and social sciences from mid-20th century onward	1920s (Fisher's blocking principle); applied to RCTs from the 1940s onward
صاحب الطريقة	Richard L. Solomon (base design, 1949); blocking integrated from classical experimental design tradition (Fisher, 1935)	R. A. Fisher (blocking principle); systematic RCT application by Bradford Hill and later Pocock, Friedman et al.
النوع	Experimental design	Experimental design
المصدر التأسيسي	Solomon, R. L. (1949). An extension of control group design. Psychological Bulletin, 46(2), 137–150.	Friedman, L. M., Furberg, C. D., DeMets, D. L., Reboussin, D. M., & Granger, C. B. (2010). Fundamentals of Clinical Trials (4th ed.). Springer. ISBN: 978-1441915856
الأسماء البديلة	Blocked S4G, randomized blocked Solomon design, Solomon four-group with blocking	blocked RCT, block-randomized trial, stratified block randomization trial, permuted block randomization
ذات صلة	6	5
الملخص	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.	A blocked randomized controlled trial (blocked RCT) uses permuted-block randomization to ensure that treatment groups remain balanced in size — and optionally in key characteristics — throughout recruitment. Within each block of fixed or randomly varied size, all treatment allocations are present in equal numbers, so imbalance cannot accumulate even if the trial is stopped early. This makes blocked RCTs the standard randomization approach in clinical and behavioral intervention research.