Do rich families talk to their kids more than poor families?

Are Children in professional families talked to three times as much as the children in welfare families? That's the underlying assumption behind a new program at Bellevue hospital designed to coach "poor families on how to talk to their infant children, encouraging more interaction."

At least, that's how the Huffington Post wants you to think about this story:

University of Kansas graduate student Betty Hart and her professor, Todd Risley, wanted to figure out the cause of the education gap between the rich and poor. So, they targeted early education and headed a study that recorded the first three years of 40 infants' lives. The conclusion? Rich families talk to their kids more than poor families.

Pretty impressive, huh? Sounds cutting edge, right? With a little searching I discovered the following:

• Betty Hart was a grad student at KU in the 1960s.
• The research data for this study was collected in the early 1980s.
• The paper publishing these results was published in 1995.

I have no problem with the common sense underlying these notions: talking to babies a lot helps them achieve higher success in academics later in life. Good advice all around, no doubt. But I'm suspicious of several assumptions about the finding of the original paper. From Alix Spiegel:

According to their research, the average child in a welfare home heard about 600 words an hour while a child in a professional home heard 2,100. "Children in professional families are talked to three times as much as the average child in a welfare family," Hart says [emphasis added].

Hearing words in your environment and talking to children are two different things and need to be distinguished, as well as child-directed speech. All I have are secondary sources not the 1995 book (Spiegel's article is the most thorough) so I can't tell how the data was coded and what they looked for (did the make the above three distinctions?).

But more to the point is the contemporary rush to paint these old findings as rationale to create new programs aimed at poor parents as if being poor makes your language use wrong somehow. It strikes me as convoluted logic to take a 15 year old book (based on 20 year old data) and decide that poor parents need linguistic intervention. Exactly how much grant money did Dr. Mendelsohn spend on this program? Even if the 3-1 ratio holds true (I suspect it would not under close scrutiny), what other factors might be affecting this?

It struck me that people with basically good intentions took a small amount of science out of context and used it to reinforce class stereotypes and class pressure.