(Dow Jones) Passage of health-care overhaul has buoyed shares of exchange-traded funds focused on the sector, in an apparent sign that investors were happy to see some of the uncertainty cleared up.

The greatest impact was seen on shares of broadly diversified health-care sector ETFs and those investing in pharmaceutical companies. Shares of Vanguard Health Care ETF (VHT), iShares Dow Jones U.S. Healthcare Sector Index Fund (IYH) and Health Care Select Sector SPDR Fund (XLV) were up about 1.15%, 1.10% and 1.05%, respectively, by Monday afternoon, although many traded down slightly at Tuesday midday, shortly after President Obama signed the bill into law.

"This was perhaps a relief rally," said Ronald DeLegge, a former financial advisor who publishes ETFGuide.com. "Investors are saying, 'OK, now it's passed into law.' But it's difficult to say what it's going to mean or translate into as far as profit margins. It will create more customers and it will create more competition."

John Gabriel, an ETF analyst with investment research firm Morningstar Inc., said investors are likely focused on the millions of new health-care customers the overhaul could bring.

"When prices get pushed down, profits will get squeezed. If volume gains are big enough, it could be a net positive," he said. "With ETFs rallying, that looks to be what the market is pricing in."

Even in the broadly diversified health-care ETFs, industry breakdowns can vary greatly, so investors should be sure they know what they are investing in, Gabriel warned. Morningstar likes iShares S&P Global Healthcare Sector Index Fund (IXJ), for example. Its ability to invest globally means it's more heavily invested in pharmaceuticals, such as Novartis AG (NVS) and Roche Holding AG (RHHBY), than some other health-care ETFs, Gabriel said. Shares of the fund were up 0.61% Monday.

Shares of ETFs investing in pharmaceuticals rose significantly. Pharmaceutical HOLDRs ETF (PPH), SPDR S&P Pharmaceuticals ETF (XPH) and PowerShares Dynamic Pharmaceuticals Portfolio (PJP) were up 1.37%, 1.79% and 1.45%, respectively.

Standard & Poor's Equity Research Group ranks about 20 ETFs investing in the health-care sector, and has an overweight ranking on several with fairly large investments in the managed-care area, said Tom Graves, an equity analyst. Among them are iShares Dow Jones U.S. Healthcare Provider (IHF), which was up 0.76% Monday, and iShares Dow Jones U.S. Healthcare Sector Index Fund.

Managed-care organizations, like pharmaceutical companies, made some significant concessions as part of the reform, but have the potential of getting 32 million new customers, said Jeffrey Loo, an equity analyst at S&P. "We think overall that the reform will be positive for the managed-care sector."

Biotechnology ETFs also rose, though not as dramatically. Shares of SPDR Biotech ETF (XBI), iShares Biotechnology (IBB), Merrill Lynch Biotech HOLDRs Trust (BBH) and PowerShares Dynamic Biotechnology & Genome Portfolio (PBE) were up 0.86%, 0.89%, 0.69% and 0.83%, respectively.