Idiosyncratic variables that affect functional analysis outcomes: a review (2001-2010).

The team read every functional-analysis paper from 2001-2010. They hunted for times clinicians tweaked the test after the first round stayed flat.

Each tweak got labeled: Was it something added before the behavior (antecedent) or after it (consequence)? The list shows what tricks are actually used when the standard four conditions fail.

Clinicians most often slip in antecedents like taking away favorite items or starting a sudden transition.

They also change what happens after the behavior, such as lifting a work demand or giving a very specific social comment. These small moves often make the function pop out.

Smith et al. (1997) first warned that hidden stimuli can flip FA results. Tassé et al. (2013) now proves the warning was real by counting a decade of real-world fixes.

Nevin et al. (2005) showed one fix: stack antecedents together. The review agrees, listing combined-antecedent edits as a common clinician choice.

Kahng et al. (1999) told us to watch minute-by-minute shifts. The review shows clinicians do this in practice, adding idiosyncratic events exactly when responding starts to drift.

When your FA graph looks flat, do not stop. Borrow from the list: try removing a preferred item, add a sudden transition, or let the child escape the task for a moment. Run one quick probe, watch the data, and pick the function that finally shows its face. Your treatment will match the real reason the behavior happens, saving you weeks of guesswork.