There are a number of warning signs to look for before a stock market downturn, but Citi Research said only a few are present now.
The firm has compiled its own checklist of 18 items to identify if global equities are about to enter a "bear" period. Although the S&P 500 is near a record high, Citi says only four of the cautionary metrics that indicate this is the top are currently fulfilled.
"Our Bear Market Checklist helps us compare current global variables to those before previous major bear markets," Citi said in a note to investors.
A bear market is synonymous on Wall Street with a broad, long-lasting decline in stocks. It's traditionally defined as a drop of 20% or more from a recent peak.
Only four of the 18 factors on its checklist "are flashing sell," Citi noted – much less than the 17½ in 2000 and the 13 in 2007, when stocks entered a prolonged decline. Citi's list counts the red as "worrying" and a full point toward the 18, while amber means "perhaps" and is worth half a point.
Citi added that, while the checklist is one of the firm's "most closely-followed" metrics, "it is not a market timing tool."
"But it does provide important guidance for whether or not you should want to buy the (market) dip," Citi added.
– CNBC's Michael Bloom contributed to this report.