School BCBA Systems Letter
Research that leads to a practical next step
You finished the FBA. Did anyone test the hypothesis?
The trap
The FBA is due before the IEP meeting. You pulled records, interviewed the teacher, got a rating scale back from the para, and collected a few ABC sheets. The hypothesis says escape from demands, and everyone nods because it matches what they already believed.
The FBA is marked complete. The BIP gets written from it. Six weeks later the plan is stalling, and the team argues about buy-in or placement. Almost nobody goes back and asks whether the function was ever right.
A form plus an interview is the start of an assessment. It is not a test. Without a rule for when descriptive information is enough, "we did an FBA" quietly becomes "we guessed and wrote it down carefully."
The better question
Not "is the FBA done," but "has anything tested this hypothesis, and does the risk justify a small test before we build the plan on it?"
Interviews, rating scales, and ABC data build a good hypothesis. Sometimes that is enough. When the behavior is dangerous, the sources disagree, or a function-based plan already failed, the hypothesis needs a test the school can actually run.
Functional analysis in public schools was shorter than the lore says
Mueller, Nkosi, and Hine summarized 90 functional analyses for 69 students in public schools. Every case started with record review, interviews, rating scales, ABC recording, and scatterplots. Those results produced the hypotheses, and conditions were only included when the descriptive data supported them. Most sessions were 5 minutes. More than 70 percent of analyses took two hours or less of session time, about 90 percent identified a maintaining variable, and 61 percent ran in the student's own classroom. Every case had parent consent and staff training on blocking and safe positioning, and some had written stop rules for sessions. Limits: trained consultants ran 80 percent of analyses, most students were autistic, aggression was the most common referral, and no treatment outcomes were reported. For a school BCBA, the point is the sequence. Descriptive work tells you which conditions to test. It does not replace testing them.
Mueller, M. M., Nkosi, A., & Hine, J. F. (2011). Functional analysis in public schools: A summary of 90 functional analyses. Journal of Applied Behavior Analysis, 44(4), 807-818.
Read the full Mueller et al. article on PubMed Central
Trial-based FA fit the school day, and showed where it can miss
Bloom and colleagues embedded brief test and control trials into classroom routines for 10 students, ages 6 to 18, in two schools for students with developmental disabilities. Attention and tangible trials ran during free play, demand trials during instruction, using a timer, a data sheet, and what was already in the room. Results matched a standard functional analysis for 6 of 10 students and partly matched for a seventh. Two mismatches resolved once trials were adjusted, including one student whose behavior only showed up when his teacher was out of the room. It was not faster, at about four and a half hours of total trial time, and interruptions from other adults and peers forced repeated trials. Graduate students ran it, not teachers. The authors call it a reasonable first test in a classroom, followed by a fuller analysis when results are unclear. That is a decision rule a school BCBA can use: pick the format the room can tolerate, and know what would make you escalate.
Bloom, S. E., Iwata, B. A., Fritz, J. N., Roscoe, E. M., & Carreau, A. B. (2011). Classroom application of a trial-based functional analysis. Journal of Applied Behavior Analysis, 44(1), 19-31.
Read the full Bloom et al. article on PubMed Central
What to do this week
1. Pull one FBA marked complete. Next to the hypothesis, list every source it rests on: records, interviews, rating scales, ABC data, observation, any test.
2. Write the hypothesis in one sentence, then write what you would expect to see if it were wrong. If nothing in the file could have shown that, it has not been tested.
3. Agree on a starting rule with your team. Lower risk, sources agree, and a function-based plan is moving the data: descriptive may be enough. Dangerous behavior, sources disagree, or a function-based plan already failed: plan a test.
4. If a test is warranted, sketch the smallest version first: which one or two conditions and their control, where, who runs it, session length, consent, safety plan, and when you stop.
Where this goes next
I'm presenting a free CEU this Friday, October 9, at 12:00 PM Pacific Time: Functional Behavior Assessment in a School Setting, hosted by CalABA's Behavior Analysts in Education SIG on BehaviorLive. We'll cover the school assessment continuum, from records review and ABC data to adapted functional analysis, plus a decision framework for picking the right format and linking findings to function-based BIP components. That includes when descriptive information is enough, when a hypothesis needs a test, and how brief, trial-based, latency, precursor, synthesized, and analog formats compare on feasibility, safety, dignity, and classroom fit. One BACB Learning CEU, free. Registrants get the recording on demand. Register for the free Functional Behavior Assessment in a School Setting CEU
If your caseload keeps producing FBAs that look complete and BIPs that stall, the missing piece is usually not a longer form. It is a school system with clear rules for when a hypothesis is good enough, when it needs a test, and how the result links to the plan staff will run. That is the work inside the School BCBA Transformation Program. The next live cohort meets six Thursday evenings, January 14 to February 25, 2027, 6 to 8 PM Pacific Time. See the School BCBA Transformation Program
See the School BCBA Transformation Program
Reply if you want: What keeps your team from testing a hypothesis? Time, safety, space, or permission?
Until next week,
Rob Spain, BCBA, IBA
Founder, Behavior School
Unsubscribe: https://behaviorschool.com/unsubscribe
Behavior School LLC