Perhaps you’ve heard that kids today desperately need more sleep. Maybe you’ve even allowed yourself to get caught up in the panic over electronic devices’ stealing our children’s slumber, to the detriment of their mental and physical health and overall well-being.

A new study says “harrumph” to all that.

Research published Monday morning in the journal Pediatrics explains that the medical and public health communities have fretted over children’s sleep deprivation for generations. Everything from radio to reading has been blamed for keeping kids from getting the shut-eye they supposedly need: “In the early 1900s, artificial lighting, radio, reading, and the cinema were considered to be the causes of delayed bedtimes,” the authors write. “By the late 1990s, video games, television viewing, the Internet, and mobile telephones were largely held responsible for such delays.”

But in all those years, the authors point out, nobody has ever presented empirical evidence to support their recommendations regarding children’s sleep needs. Nobody has actually figured out exactly how much sleep children really need, how much they get, or how lack of sleep might affect their bodies, minds, or any other aspect of their lives.

Researchers at the University of South Australia read widely in both scientific and popular literature about recommendations regarding kids’ need for sleep, starting when the matter first emerged as an issue of concern in the late 19th century. Curiously, the only era during which no specific recommendations for duration of kids’ sleep were made was the mid-to-late 20th century, during which time researchers were more interested in the physiology of sleep and sleep regulation.

The article makes the fascinating observation that, across all age groups, recommendations for the amount of sleep kids and teens need have decreased about 0.71 minutes per year, for a total of 70 minutes over the course of the 20th century. At the same time, the actual amount of time kids have spent sleeping has declined by almost exactly the same amount — 0.73 minutes per year. Whether in 1897 or 2009, children have consistently got about 37 fewer minutes’ sleep than recommendations called for.

The authors make no bones about the irrationality of the situation. One of the consistencies they found in the sleep literature, whatever its era, was the acknowledgement that the recommendations were basically drawn out of thin air.

The authors note in their brief conclusion that we know much more about the mechanisms by which nutrition, physical activity and sedentary behavior influence children’s health. It’s high time, they suggest, that we get busy learning more about how sleep — or lack thereof — actually affects kids.

In the end, the authors note, “No matter how much sleep children are getting, it has always been assumed that they need more.”