NEW YORK (Reuters) -U.S. bond firm DoubleLine said on Wednesday it is using a variety of official and private data sources to assess the health of the U.S. economy, as it is worried about a decline in the quality of data published by the Labor Department's Bureau of Labor Statistics.

In August the Bureau of Labor Statistics published sharp downward revisions to previous jobs data, jolting markets and raising investor worries the Federal Reserve may have been flying blind and would need to catch up with interest rate cuts. President Donald Trump said at the time, without evidence, that numbers contained in the July jobs report were rigged and removed the head of BLS, exacerbating concerns about the integrity of U.S. economic data.

"At DoubleLine, we take a holistic approach to monitoring the health of the economy," Ryan Kimmel, fixed income allocation strategist at DoubleLine, said in a note.

DoubleLine monitors official data, including BLS reports, but complements them with private datasets, corporate earnings calls, and views from in-house experts on corporate debt, consumer lending, and commercial real estate and mortgage lending, said Kimmel.

"Confronted by challenges to the accuracy and reliability of BLS data ... it is more important than ever to possess robust, multifaceted approaches to economic analysis," he said.

The BLS did not immediately respond to a request for comment.

Kimmel pointed to a drop in participation rates in the poll of employers that BLS uses to produce its monthly jobs report, from 60% in the 2010s to 40% in recent years.

With responses to employment surveys declining, BLS has relied more on statistical imputation, which uses models to estimate missing data based on historical trends or trends in certain sectors.

"The more data is inferred instead of collected, the risk of mismeasurement grows," said Kimmel.

The Fed cut rates by 25 basis points last week after recent data showed unemployment climbed to 4.3% in August and payrolls grew far less than expected. A steep downward revision to jobs figures for the year through March also recently added weight to the view that the labor market is losing steam, strengthening the case for multiple rate cuts ahead.

"The decline in data quality at the BLS undermines the reliability of economic analysis, putting businesses, policymakers and markets at risk," said Kimmel. "Should this trend continue, it could lead to increased uncertainty and diminished confidence throughout the economy."