In-Depth Notes on Multiple-Probe Technique

Overview of the Multiple-Probe Technique

  • Definition: The multiple-probe technique combines multiple-baseline and probe procedures to analyze the relationship between an independent variable and the acquisition of a sequence of successive approximations or chains.
  • Purpose: To provide insights on:
  1. Initial levels of performance on each training step.
  2. Effects of providing sequential opportunities for performance before training.
  3. Outcomes when training is applied.
  4. Performance changes in remaining steps as each step is trained.

Components of the Multiple-Probe Technique

  • Features:
  1. Initial probe of each training step.
  2. Additional probes after each training step reaches criterion.
  3. True baseline sessions before introducing independent variable for each step.
  • Intermittent Probes: These are used to circumvent issues with continuous baseline measurements, particularly when
  • They may cause reactivity,
  • Are impractical, or
  • Stability can be assumed a priori.

Applications of the Technique

  • Chain of Successive Approximations:
  • Initial probe session for each step in training.
  • Additional probing after criterion attainment at each step.
  • True baseline sessions before introducing the independent variable.
  • Example:
  • Hypothetical application for teaching crutch usage to a child with spina bifida, with data showing progression through steps of training based on initial and subsequent probes.

Performance Assessments

  • Questions Addressed by the Technique:
  1. Initial performance levels on each training step.
  2. Impact of pre-training opportunities on subsequent training steps.
  3. Effects of actual training on performance.
  4. Observations of remaining steps as each criterion is achieved.
  • Hypothetical Outcomes: Assessments can demonstrate whether initial changes were due to the training or merely incidental based on probe performance.

Alternatives to Continuous Measurement

  • Concerns with Continuous Baselines:
  • Continuous measurements can lead to reactive behaviors under experimentation, leading to challenges like extinction, boredom, or fatigue.
  • The multiple-probe technique operates by using fewer, targeted observations to avoid these pitfalls.
  • Examples from Literature: Shows successful implementations of multiple-probes replacing traditional continuous measurement methods in various studies, addressing word production, imitation, and other behaviors.

Discussion of Limitations

  • Reduced Opportunities: Compared to traditional multiple-baseline designs, the multiple-probe technique offers fewer opportunities for observing behavior before introducing the independent variable.
  • Potential for Ambiguity: Increases in untreated steps following an intervention can obscure the specific cause (treatment effects versus extraneous variables).
  • Reversal Designs Recommendation: Employing reversals can help clarify treatment efficacy and rule out alternative explanations for observed changes.

Conclusion

  • Functional Analysis of Behavior: The multiple-probe technique is an effective tool for analyzing behavior acquisition through controlled and focused assessment methodologies, especially in settings where continuous measures are impractical or disruptive.