• Why we need to individualize our functional analyses
• How Fisher et al. (2023) classified modifications to traditional FA procedures
• Examples of antecedent and consequence modifications
• Common idiosyncratic functions you might identify in practice
• Practical strategies for pivoting from inconclusive to clear functional outcomes
• Key research articles you should add to your personal library

As always, I’ve written these notes in first person to reflect how I use them in my own practice and to serve as a resource you can bookmark, print, or share with colleagues. Let’s dive in!

1. Episode Overview

In this episode I emphasize that although the functional analysis (FA) is the gold standard for assessing the function of problem behavior, it often produces “messy” or undifferentiated data in clinical practice. Rather than giving up or settling for an inconclusive result, it’s crucial to systematically modify your FA conditions to capture idiosyncratic variables relevant to your learner. Sanny Fisher, Reland, and their team conducted a comprehensive literature review (over 100 empirical studies!) to classify the types of FA modifications used in real-world cases. In doing so, they provide a practical roadmap for behavior analysts who need to pivot from a standard FA to an individualized assessment that yields clear, intervention-informing outcomes.

2. Why Standard FAs Sometimes Fail in Practice

• Research vs. practice gap: Research environments yield clean graphs; in practice, clients get sick, settings change, and confounds emerge.
• File-drawer problem: “Failed” FAs rarely get published, so clinicians don’t see the messy side of the literature.
• One-size-does-not-fit-all: Standard FA conditions may not represent true contingencies for each individual.
• True goal: Identify functional relations that will guide your subsequent intervention, not just run four standard conditions.

3. Fisher et al. (2023): Scope and Objectives

In Journal of Applied Behavior Analysis, Volume 52, Issue 3, Fisher and colleagues set out to:

1. Classify the types of FA modifications employed across empirical studies
2. Identify common idiosyncratic variables that prompted modifications
3. Provide guidance and strategies for behavior analysts to adapt FA protocols when initial assessments are inconclusive

“We reviewed over 100 empirical studies that modified FA conditions to account for idiosyncratic variables, with the goal of turning inconclusive, jumbled data into clear, differentiated results.”

4. Classification of FA Modifications

A. Antecedent Modifications (59.7% of reviewed studies)

• Altering setting events (home vs. clinic)
• Varying the person delivering demands or attention
• Adjusting task type, difficulty, or demand sequence
• Manipulating environmental stimuli or routines that precede problem behavior

Examples:

• Switching from nonpreferred academic demands to IEP-aligned tasks
• Delivering attention from a peer instead of an adult therapist
• Conducting FA immediately after a known setting event (e.g., transition)

B. Consequence Modifications (38.2% of reviewed studies)

• Introducing novel or highly preferred tangible items
• Allowing escape from highly specific tasks
• Delivering attention in the modality the individual finds reinforcing
• Using ritualistic responses rather than generic praise

Examples:

• Escape specifically from academic worksheets rather than any work task
• Access to a specific video game console rather than generic toys
• Removing the session and sending the learner to recess

Both antecedent and consequence modifications led to clear outcomes in over 90% of reviewed studies.

5. Common Idiosyncratic Functions

• Access to ritualistic or self-stimulating routines
• Escape from very specific tasks (e.g., math but not reading)
• Attention from specific people (e.g., grandparent vs. any adult)
• Activity interruption (pausing a video game but not a tablet)
• Social avoidance (escape from group play but not individual work)

These side functions rarely appear in standard FA conditions, highlighting the value of thorough caregiver interviews.

6. Practical Roadmap for Modifying Your FA

1. Re-examine your caregiver interview: Were all setting events and reinforcers explored?
2. Identify candidate idiosyncratic variables: Note clues that don’t fit standard scenarios.
3. Modify antecedents or consequences: Use the exact triggers or rewards identified.
4. Run an abbreviated FA: Brief, focused sessions comparing tailored vs. control conditions.
5. Evaluate differentiation: Move to intervention design or repeat modifications if needed.
6. Document and graph: Share even messy data to help close the file-drawer problem.

7. Key Articles in FA Literature

• Iwata et al. (1982/1984) – Pioneering experimental FA of self-injurious behavior.
• Hanley, Iwata & McCord (2003) – Review of FA variations.
• Hanley (2014) – Interview-Informed Synthesized Contingency Analysis (ISCA).
• Fisher et al. (2023) – Review of FA methods for idiosyncratic variables.

8. Bridging Research and Practice

I apply Fisher et al. (2023) by conducting thorough intake interviews, preparing for common idiosyncratic variables, and viewing messy data as learning opportunities. I share outcomes in team meetings and peer forums to advance our field.

9. Key Takeaways and Action Steps

• Always individualize your FA with an open-ended interview.
• Revisit antecedents/consequences when results are undifferentiated.
• Use brief, focused test conditions to isolate idiosyncratic variables.
• Repeat FAs as needed—it’s part of the scientific process.
• Document every iteration and share your data.

10. Recommended Next Steps

1. Read Fisher et al. (2023) for the complete classification table.
2. Revisit Iwata et al. (1982/1984) for early FA nuances.
3. Explore Hanley’s (2014) ISCA methodology.
4. Integrate open-ended interviews into intake procedures.
5. Plan an in-service on FA modifications using real case examples.

11. References

• Fisher, S., Reland, L., & Colleagues. (2023). A review of functional analysis methods for addressing idiosyncratic variables. Journal of Applied Behavior Analysis, 52(3), 450–478.
• Iwata, B. A., Dorsey, M. F., Slifer, K. J., Bauman, K. E., & Richman, G. S. (1982/1984). Toward a functional analysis of self-injurious behavior. JABA, 13, 197–209.
• Hanley, G. P., Iwata, B. A., & McCord, B. E. (2003). Functional analysis of problem behavior: A review. JABA, 36(2), 147–185.
• Hanley, G. P. (2014). Functional assessment of problem behavior: Dispelling myths, overcoming implementation obstacles, and developing new lore. Behavior Analysis in Practice, 7(1), 54–72.