Diffusion effects: Control group contamination threats to the validity of teacher-administered interventions
Within-class experimental designs (with experimental and control groups in the same classroom) are subject to diffusion effects whereby both experimental and control students benefit from the intervention, thereby contaminating the control group and biasing evaluations of intervention effects. Altho...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
2001
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