Evaluating the duration of the competing response in habit reversal: a parametric analysis.

Researchers tested how long a client must hold the competing response in habit reversal.

They used an alternating-treatments design with three durations: 5 seconds, 1 minute, and 3 minutes.

The target behavior was nail biting, and the outcome was actual nail growth over time.

Only the 1-minute and 3-minute durations grew nails back.

The 5-second squeeze did not work; nails stayed short.

One minute was as good as three, so longer is not always better.

Clarke (1998) extends this work to teen athletes. They added response cost to simplified habit reversal and wiped out disruptive outbursts on the tennis court.

Van Houten et al. (1980) used the same alternating-treatments design to shape key-peck durations in pigeons. Both studies show that small time tweaks can flip success or failure.

Repp et al. (1987) treated thumb sucking and saw untreated hair pulling vanish too. This hints that the nail-growth success here might spill over to other habits without extra work.

If you run habit reversal for nail biting, hair pulling, or skin picking, tell the client to hold the competing response for a full 60 seconds. Skip the quick 5-second squeeze—it wastes time. This one change can turn a stalled program into clear, visible progress.