A brouhaha is brewing between the National Association of Realtors and some members of Congress over the association's assessment of congressional voting records. Each side has accused the other of playing dirty.

Like other special interest groups, the trade association has rated House and Senate members on the basis of how they voted during the recent session on nearly 200 bills and amendments. The issues ranged from housing to windfall profits, common site picketing and water reclamation. Comparing the legislator's record to its own stated positions, the NAR came up with individual report cards.

The association determined that Republicans voted "correctly" on 90 percent of the issues in the House and 84 percent in the Senate. House Democrats, on the other hand, voted "correctly" on only 29 percent of the issues, while their Senate colleagues did so on 28 percent.

But the NAR did not stop at analyzing voting records. The organization ran them through a computer and predicted the consequences of each decision it viewed as negative.

For example, the report card for Rep. David R. Obey (D-Wis.) declared about his vote on long-term interest rates: "By 1985, Congressman Obey's votes during 1977 through July 1980 would have caused housing starts to be 19,050 units or 42.1 percent lower in Wisconsin. Existing home sales would be 41,910 units lower."

On the subject of consumer prices, Obey's report card said: "If the important economic policy issues were passed because of Congressman Obey's votes, consumer prices in Wisconsin in 1980 would be 3.6 percent higher than they would otherwise have been."

Copies of each legislator's report card were sent to real estate associations, agents and brokers back home in his or her district in August. Five members of Congress contacted this week indicated that they had not experienced any backlash from local real estate agents, media or constituents.

In face, Rep. Bruce F. Vento (D-Minn.) said the report card had backfired in his district. He said that embarrassed real estate agents apologized to him for this "outrage" the Democratic candidate for reelection a campaign contribution. Asked if he had complained to NAR, Vento replied, "I wouldn't waste my time."

Nevertheless, according to NAR, 150 legislators were impressed or angry enough to call or write the association. The NAR noted, "In the negative responses -- which represented about one-third of all the comments recorded -- there were personal threats aimed at our executive vice president, including IRS audits, special investigations and attempts to get him fired."

What the legislators objected to was the methodology involved in analyzing their voting records. As explained by the Democratic Study Group, chaired by Obey, NAR based its report primarily on party-line votes "in which it arbitrarily assigned adverse economic consequences to whichever way the majority of Democrats voted in order to assure that the overwhelming majority of Democrats get poor ratings while Republicans receive good marks."