What Counts as One Discrete Trial in ABA?

Define one discrete trial ABA teams can reproduce

Name the cue, eligible materials, who presents it, when timing begins, the response definition, response window, prompt timing, consequence, correction path, and event that closes the trial. Another trained observer should be able to identify the same boundaries.

Prevent denominator inflation

Do not count a staff repetition as a new independent opportunity unless the procedure defines a new trial and the conditions reset. Record early responses, multiple responses, self-corrections, requested help, and interrupted events according to written rules.

Keep invalid trials visible

Missing materials, wrong cues, device outages, staff timing errors, safety interruptions, and client withdrawal may make an opportunity invalid for the target calculation. Report each reason and the original planned-trial count so invalid events do not disappear.

Use sources as conceptual anchors

The BACB outline covers trial-based arrangements, measurement, prompts, integrity, and evaluation. The CDC page offers general DTT orientation. The Ethics Code addresses documentation and data-based review for covered people.

A practical example

A plan schedules twelve symbol trials. Staff present the wrong card once, the tablet fails once, and Ellis declines once. Nine valid trials remain: four independent, three prompted, one incorrect, and one no response. Report 12 planned, three excluded by reason, and all four valid response categories.

Questions families can use

What starts and ends a trial? Does a repeated cue count again? Which prompt changes the category? Which events are invalid? Are planned, valid, and completed trial counts all visible?