ITHACA, N.Y. — Nutrition Report Cards (N.R.C.s) may be a “feasible and inexpensive tool to guide children towards healthier choices,” according to a study from researchers at Cornell University.

The study, “Nutrition Report Cards: An opportunity to improve school lunch selection,” involved 35 students in grades K-12 at a rural school district in New York. As part of the study, over a five-week period, parents received a weekly e-mail containing a N.R.C. listing how many meal components (fruits, vegetables, starches, milk), snacks and a la carte foods their child selected.

What the researchers found was the report cards encouraged more home conversations about nutrition and more awareness of food selections.

“Despite the small sample, the N.R.C. was associated with reduced selection of some items, such as the percentage of those selecting cookies, which decreased from 14.3% to 6.5%,” said the researchers, led by Brian Wansink and David Just. “Additionally, despite requiring new keys on the check-out registers to generate the N.R.C., checkout times increased by only 0.16 seconds per transaction, and compiling and sending the N.R.C.s required a total weekly investment of 30 minutes of staff time.”

The researchers said the N.R.C. is similar in concept to a Body Mass Index (B.M.I.) Report Card that has been used at schools in Arkansas since 2003. Research has shown that the B.M.I. report cards may encourage increases in children’s exercise and help parents more accurately assess their child’s health.

As for the N.R.C.s, Cornell researchers noted they may positively influence food choice through the child’s perception that parents are observing their choices. Also a possibility is that parents may use the N.R.C.s to set eating goals or limit a child’s a la carte purchases.

“This pilot study underscores that a N.R.C. intervention is feasible and efficient,” the researchers said. “Additionally, while this study was not designed to test the effectiveness of N.R.C., preliminary results provide hope for their capacity to improve children’s food selection. Although the results are preliminary, they suggest that N.R.C.s may be helpful in nudging children towards more healthy, less expensive options and away from less healthy, more expensive ones and to do so at little cost to the school district.”