The Solomon Four-Group Design
The fi rst remedy is to use a design called the Solomon four-group design.Probst was interested in studying the relationship between organizational restructuring (e.g., agency mergers and management reorganization) and
various measures of employee reactions (e.g., perceived job security and emotional
reactions).By comparing this effect
with the impact of your treatment when a pretest is included, you can determine
whether inclusion of the pretest alters the effect of your treatment.Note that four groups are included in this
design.