Measurement, Data Display, and InterpretationDifficulty 3/5
Baseline shows a clear increasing trend in the therapeutic direction. Intervention is introduced and the behavior continues to increase at the same rate. What is the most defensible interpretation?
- AInterobserver agreement must be low, because a real effect would show a level change
- BThe intervention produced a strong effect, shown by continued improvement in the therapeutic direction
- CThe data do not demonstrate experimental control because the baseline trend already predicted this outcome
- DThe intervention should be intensified immediately to accelerate the existing trend
Show answer and rationale
Correct: C. A baseline trending in the therapeutic direction predicts continued improvement without treatment. When the intervention phase merely continues that trend, level and trend changes cannot be attributed to the intervention.
- B — An unchanged trend is not evidence of an effect.
- D — Intensifying before establishing control compounds the interpretation problem.
- A — Nothing in the scenario speaks to measurement agreement.