A long-range study on how parents discipline their kids shows a clear trend: spanking is down and time-outs are up. The Georgetown researchers looked specifically at national surveys involving mothers with kindergarten-age kids and found that modern parents across all income levels report spanking their children less than their counterparts in 1988, reports Live Science.

For example, the percentage of average-income mothers who endorsed the idea of spanking dropped from 46% in 1988 to 21% in 2011. At the same time, the overall percentage of mothers who backed non-physical time-out punishments rose from 41% to 81%.

One researcher not involved with the study cautions that what parents say they do may be different than what they actually do inside their home. Still, "parents seem to be using more reasoning and nonphysical discipline strategies with children, which is in line with what the American Academy of Pediatrics recommended in 1998," says lead researcher Rebecca Ryan, per HealthDay.

Generally speaking, the lower the income, the more likely mothers were to endorse physical discipline. About a third of those in the bottom 10% of incomes backed the idea in 2011, and 25% had actually spanked their kids in the previous week.

More From Newser

Still, the researchers say in the American Academy of Pediatrics that "changes have occurred at all socioeconomic levels, producing for some behaviors a significant reduction in socioeconomic differences."

This article originally appeared on Newser: How We Discipline Kids Has Changed, or So Say Parents