পদ্ধতির তুলনা করুন

	ব্লকড এবি ডিজাইন	ব্লকড র‍্যান্ডমাইজড কন্ট্রোলড ট্রায়াল
ক্ষেত্র	পরীক্ষামূলক নকশা	পরীক্ষামূলক নকশা
পরিবার	Process / pipeline	Process / pipeline
উদ্ভবের বছর	1970s–1980s (systematic development of blocked randomization in single-case research)	1920s (Fisher's blocking principle); applied to RCTs from the 1940s onward
প্রবর্তক	Based on Fisher's randomized block principle (1926) applied to single-case AB designs	R. A. Fisher (blocking principle); systematic RCT application by Bradford Hill and later Pocock, Friedman et al.
ধরন	Single-subject experimental design with blocking	Experimental design
মৌলিক উৎস	Edgington, E., & Onghena, P. (2007). Randomization Tests (4th ed.). Chapman and Hall/CRC. ISBN: 978-1584885894	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
অপর নাম	blocked AB single-case design, randomized block AB design, AB design with blocking, blocked baseline-treatment design	blocked RCT, block-randomized trial, stratified block randomization trial, permuted block randomization
সম্পর্কিত	6	5
সারসংক্ষেপ	The Blocked AB Design applies the logic of randomized block experimental design to the classic single-subject AB framework. Observation sessions are organized into blocks — matched sets of time points or contextual units — and the assignment of baseline (A) and treatment (B) phases is randomized within each block. This controls for nuisance time-based variability while preserving the interpretive simplicity of the fundamental two-phase single-case structure.	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.