(Bloomberg) -- A U.S. Department of Agriculture proposal to overhaul how hog slaughterhouses are inspected and allow faster production lines relied on flawed data that played down dangers to workers, according to a academic report issued on Wednesday.

The USDA announced the inspection proposal in January. It would shift some of the responsibilities of federal inspectors to plant workers and lift caps on how fast hogs can be slaughtered as they move along the production line. Line speeds have historically been limited by the ability of government inspectors to examine each carcass. In hog plants, line speeds are currently capped at 1,106 hogs per hour.

As part of its inspection proposal, the USDA said five plants that had participated in a pilot program had “lower mean injury rates” than did traditional plants used for comparison.

Celeste Monforton, a lecturer in public health at Texas State University, and Phillip Vaughan, a research scientist at the school, reviewed the data behind the USDA’s assertion, which was obtained via a Freedom of Information Act request. They concluded there were too many limitations with the data to support the USDA’s assertion, which they said was based on “the most rudimentary analysis.”

For instance, they said that the pilot plants weren’t selected randomly and that the sample size used by the agency was too small. In addition, the USDA didn’t have the same amount of data from each of the plants that it compared: the agency had consecutive years of data for only 8 of the 24 traditional plants it used in the analysis and only three of the pilot plants; none had data for the full nine-year period of analysis.

“They just added them all up and made an average,” Monforton said. “I was like, really?”

A USDA spokeswoman said the agency wasn’t immediately able to provide a comment. In a previous interview, the agency said it stood by its analysis of the data.

Serious injuries requiring work restrictions or days away from the job are more than three times as high in the meatpacking industry than in U.S. industries as a whole, government data shows.

“In plain language, the USDA’s analysis is a joke,” said Debbie Berkowitz, program director for worker safety and health with the National Employment Law Project, who called on the USDA to conduct a more robust study of the inspection proposal’s impact on workers. “USDA is using a faulty data analysis, one that it tried to hide from the public, to justify a proposal that will clearly endanger workers.”

To contact the reporter on this story: Andrew Martin in New York at amartin146@bloomberg.net

To contact the editors responsible for this story: Jeffrey D Grocott at jgrocott2@bloomberg.net, David S. Joachim

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