Blocked Solomon Four-Group Design
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.
Source record
Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.
- Solomon, R. L. (1949). An extension of control group design. Psychological Bulletin, 46(2), 137–150. · DOI 10.1037/h0062958
- Kirk, R. E. (2013). Experimental Design: Procedures for the Behavioral Sciences (4th ed.). Sage Publications. · ISBN 978-1412974455
Curated claims
Claims persisted in the evidence ledger, each with its own assessment.
This view does not invent a claim assessment when the ledger has none.
Related methods
Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.