Low interest rates have many investors searching for high-yielding investments. Many are focusing on stocks paying robust dividends.

There are good reasons to search for dividend payers. Large stocks currently sport dividend yields about twice the yield on 10-year Treasury notes, a rare occurrence.

"The last time stocks looked this attractive on dividend income relative to Treasurys was back in the 1950s," says Tobias Levkovich, Citigroup's chief U.S. equity strategist. He notes that dividends often were ignored in recent decades, but they nonetheless have "provided half of the return from stocks," another reason to be on the lookout for juicy dividends.

Mr. Levkovich says high dividend payers should be in focus even though tax treatment on dividends could change if the tax reduction enacted under President Bush isn't extended.

Troubled Payers

But not all high-dividend stocks are created equally, and there are pitfalls to chasing these investments. Some dividends are high but are paid by companies with deteriorating businesses, for example. Even if they continue to pay the dividends, stock prices could fall, essentially canceling out those dividend payouts. Other companies may not be able to continue to pay hefty dividends.

Jason Schneider

As a result, reasonable and safe dividends sometimes are better bets than huge dividend payouts, analysts say. Indeed, in a period when 10-year Treasurys pay a skimpy yield of about 1.7%, a stable stock with a dividend yield of more than 3% is attractive, some analysts say.

"As an investor, you want to stick with companies that have shown a consistent capability of increasing—not just maintaining—their dividend payments," says Alan Zafran, co-founder of Luminous Capital, a California investment adviser.

A sky-high dividend yield might attract investor attention, but it could be the result of a falling stock price stemming from problems at a company. When a falling stock price is coupled with nervousness about a company's debt, it can be an especially worrisome combination, analysts say.

Shares of Pitney Bowes (PBI) have a dividend yield of 10.7%. But the stock is down 34% over the past two years. At the same time, credit-default swaps, or derivative contracts that serve as protection against a default of the business communications company's debt, trade at levels indicating some concern about the company's health, according to Markit.com, a financial information services company.

With a 6.4% dividend yield, Cliffs Natural Resources (CLF) is down 36% and also has swaps at levels indicating some nervousness among debt investors. "Sustaining the dividend is a major priority for Cliffs' management," said a spokeswoman for Cliffs.

Meanwhile, Lexmark International (LXK), with a 5.4% yield, is down about 47% in the past two years. Lexmark's swap levels have been worsening over the past year, as have those of Pitney Bowes, though Cliffs' swaps haven't moved much in that period.

Falling stock prices don't necessarily mean a dividend will be trimmed, of course, and investors could make out well with these companies if the stocks stabilize and the dividends aren't reduced.

Stocks Like Bonds

"The stocks we would avoid are those that exhibit bond-like characteristics—high dividend yields but little or no growth potential, " says Richard Platte Jr., who runs the Ave Maria Rising Dividend Fund (AVEDX). "Another area to avoid would be companies, or industries, where secular change is impairing prospects for future dividend growth." He includes Avon Products (AVP), which has a dividend yield of 5.8%, and printer R.R. Donnelly (RRD), with a yield of 9.5%.

Darren Schuringa, managing partner of Yorkville Capital, is wary of Oxford Resource Partners (OXF), a master limited partnership in the coal business that has a yield of 19%.

"Investors are basically waiting for a cut in distribution," Mr. Schuringa says. "The coal MLP has faced pressure from possible [environmental] legislation and increased adoption of natural gas as an energy source."

Some investors are flocking to MLPs, investments which often have big payouts (technically called "distributions," not dividends) backed by energy pipelines generating steady revenue under long-term contracts. But some recent MLPs have been introduced based on less-reliable revenue streams. Some warn they could pay no income in some quarters.

Citigroup points to a group of stocks with sizable dividends that have credit default swaps that trade at levels suggesting little reason for concern. Among these safer stocks: Drug maker Bristol-Myers Squibb (BMY) and power company Dominion Resources (D), which both have dividend yields of about 4%, and pharmaceutical company Johnson & Johnson (JNJ), which has a 3.5% dividend yield.

Jack Ablin, chief investment officer at Harris Bank, is a fan of telecommunications shares, which have an average yield of 4.5%, well above the 1.5% yield of consumer-discretionary stocks. He recommends Verizon Communications (VZ) and AT&T (T), both with yields in line with other telecoms.

Mr. Zafran likes the Vanguard Dividend Appreciation ETF (VIG), an exchange-traded fund with a dividend yield of more than 2% that's "an easy and cost-efficient way to gain such exposure to a basket of stocks that have a history of increasing their dividends for at least 10 consecutive years."

Energy Plays

For those seeking higher dividends, Mr. Schuringa recommends QR Energy (QRE), an energy production and exploration MLP currently yielding 10%. He notes that the distribution has been rising and that QR Energy has hedged most of its production until 2015.

Meanwhile, SteelPath Capital Management's director of research, Brian Watson, recommends NuStar Energy (NS), a "truly cheap" MLP that owns and operates oil pipelines, with a yield of nearly 9%. And Mr. Platte is a fan of Emerson Electric (EMR), which has a dividend yield of 3.3% and "has had a long record of raising its dividend."

Just be careful when focusing on dividend shares, analysts say. Those with the safest, most reliable dividends often are slower-growth companies liable to underperform the overall market in a rally.

James Paulsen, chief investment strategist at Wells Capital Management, adds that if bond yields rise, as their prices fall, shares paying hefty dividends could take it on the chin, as investors shift back into bonds to capture those payouts.

Write to Gregory Zuckerman at gregory.zuckerman@wsj.com