ABA Exam Coach

C.9: Select a measurement procedure to obtain representative data that accounts for the critical dimension of the behavior and environmental constraints.

Free practice questions for this part of the BCBA, with an explanation for every option.

A client's tantrums happen about twice a day. They vary from 1 minute to 45 minutes, and the family's main complaint is how much of the day tantrums take up. Which measurement best captures the critical dimension?
  1. A. Latency from a demand to tantrum onset
    Incorrect. Latency could help with analyzing function, but it does not measure how much of the day tantrums occupy.
  2. B. Partial-interval recording with 10-minute intervals
    Incorrect. Long partial intervals would greatly overestimate tantrum time and blur differences between episodes.
  3. C. Count of tantrums per day
    Incorrect. A 1-minute and a 45-minute tantrum would each count once, which hides the dimension the family cares about.
  4. D. Duration of each tantrum, summed into total duration per day
    Correct. Duration directly captures how much time tantrums take up, which is the socially important dimension here.
A general education teacher with 25 students agrees to collect data on a student's out-of-seat behavior. When it happens, out-of-seat behavior often lasts several minutes. The teacher is teaching all day and cannot watch the student continuously. Which procedure is most appropriate?
  1. A. Event recording of each time the student leaves his seat
    Incorrect. Event recording requires continuous observation and does not capture how long the student is out of seat.
  2. B. Momentary time sampling: a vibrating timer cues the teacher to glance at the student every 5 minutes and record whether he is in or out of his seat
    Correct. MTS works well for ongoing behaviors and requires only brief, scheduled observations, which fits the teacher's constraints.
  3. C. Partial-interval recording with 10-second intervals
    Incorrect. Watching continuously in 10-second intervals is not feasible for a teacher who is teaching.
  4. D. Continuous duration recording with a stopwatch
    Incorrect. Continuous timing requires attention the teacher cannot give while teaching.
An adult in a day program has severe property destruction (e.g., breaking windows) about 1–3 times per week, usually in brief, discrete bursts. Staff are present all day but are busy with several clients. A consultant suggests momentary time sampling every 15 minutes. What is the best response?
  1. A. Agree. MTS is efficient and fits busy staff.
    Incorrect. MTS is suited to high-rate or long-lasting behaviors. Brief, infrequent bursts would almost never be happening at the sampled moment.
  2. B. Recommend whole-interval recording with 1-minute intervals.
    Incorrect. Whole-interval needs continuous attention and is unsuited to brief behaviors, which rarely fill an entire interval.
  3. C. Recommend event recording of every instance across the whole day, because MTS would likely miss brief, low-rate behavior.
    Correct. Low-rate, discrete, high-impact behavior is noticeable enough for busy staff to record each instance, and event recording captures all of them.
  4. D. Recommend a weekly staff rating scale of how often destruction occurred.
    Incorrect. A rating scale is an indirect measure, less accurate than direct counts of an easily noticed event.

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