This story was co-published with the Los Angeles Times.

More than two decades ago, Congress set out to stop dangerous or incompetent caregivers from crossing state lines and landing in trouble again.

It ordered up a national database allowing hospitals to check for disciplinary actions taken anywhere in the country against nurses, pharmacists, psychologists and other licensed health professionals.

On March 1 – 22 years later – the federal government finally plans to let hospitals use it. But the long-awaited repository is missing serious disciplinary actions against what are probably thousands of health providers, according to an investigation by ProPublica in collaboration with the Los Angeles Times.

Some of the missing cases involve providers who have harmed patients – a nurse, for instance, whose license was pulled after she injected a patient with painkillers in a drugstore parking lot and improperly prescribed methadone to an addict who later died of an overdose.

The omissions took federal health officials by surprise. Only last month, a spokesman for the agency that oversees the database told reporters that "no data is missing." Another official said the agency had been "constantly" checking its data against state licensing board Web sites.

But Friday, the head of the Health Resources and Services Administration (HRSA) acknowledged that records were missing. She said her agency had launched a "full and complete" review to determine what is wrong and how to fix it.

"We take this very seriously," administrator Mary Wakefield said.

The new information will still go online as planned – but with a warning that it is incomplete, she said.

Wakefield and Health and Human Services Secretary Kathleen Sebelius sent a letter Friday to the nation's governors asking for their immediate help fixing gaps in the database. It was a matter of "protecting the safety of patients across this country," they wrote.

This summer, the letter said, the federal government will begin publicly listing any state agencies that do not report properly. Wakefield's agency also plans to hold training sessions for state officials and conduct audits to help ensure compliance.

The government for two decades has kept a database of disciplinary actions against doctors and dentists. In 1999, state boards were required to begin filing reports on all other health professionals whose licenses were revoked or restricted.

Yet many states have filed sporadically, if at all. They've faced no penalties.

Reporters compared the total number of disciplinary actions that various states reported to the federal government – detailed on the HRSA Web site – to the states' own records, some of which were posted online. The discrepancies were glaring.

The federal government's site does not include a single report of discipline against any of the thousands of psychiatric technicians or occupational therapists in California.

Yet the Web site for the California board overseeing psychiatric technicians cites 84 who received severe sanctions in the last two years alone. Among them are two who surrendered their licenses after failing to help a woman who was choking to death on a paper towel and a third convicted of possessing child pornography.

Similarly, the occupational therapy board lists 40 disciplinary actions over five years.

Leaders of both state boards acknowledged that they hadn't been reporting disciplinary cases to the federal government but said they intended to do so in the future.

Judging from the federal numbers, no pharmacist has been disciplined in South Dakota or New Hampshire, and only one each in Alabama, Delaware, Ohio and Tennessee. But a search of those states' Web sites showed hundreds of sanctions.

Reporters found at least nine states that appear to have submitted incomplete records on registered nurses.

Indiana didn't report hundreds of disciplinary actions in 2004 and 2005 – including the nearly 100 nurses who were indefinitely barred from caring for patients. In one case, a nurse had put a knife to a co-worker's throat.

It's difficult to quantify how much data is missing. In each state, multiple boards oversee various health practitioners. Each has different rules and methods for meting out discipline. Some don't make the information public, and others said they didn't know the number of actions they'd taken.

Troubled professionals can have licenses in multiple states, so checking with just one state's board might not turn up disciplinary actions elsewhere. Moreover, state regulators can be slow to share information with one another, and some professionals hide past sanctions.

Several directors of state licensing agencies said they had assumed that their cases were being reported to the federal government.

Sean Gorman, the director of Indiana's nursing board, learned from reporters that hundreds of his state's actions against nurses had not been. That prompted Indiana to audit compliance by all of the state's health boards.

In Ohio, William T. Winsley, executive director of the pharmacy board, said he had no idea that only one of his state's pharmacist cases had been reported. At his board's November 2009 meeting alone, it pulled the licenses of five, including one who ran an Internet pill mill that dispensed nearly 1.5 million drug doses without valid prescriptions.

The database has had a long and fitful history.

In 1986, amid concerns that doctors were racking up malpractice accusations and then moving freely to other states, Congress called for a central repository of disciplinary actions against them. The next year, lawmakers expanded the requirement to include all health care workers.

The idea was to create a one-stop clearinghouse that hospitals and other eligible employers could check. The National Practitioner Data Bank was up and running quickly on doctors and dentists, but a series of logistical, technological and financial hurdles delayed its expansion. Some 280,000 nurses and other practitioners are to be added March 1.

Federal officials predict that the new information will be searched more than 123,000 times annually by health employers and others. The database is not open to the public.

Hospital industry officials said they welcomed the database but emphasized that it's just one tool for screening potential hires, along with criminal checks, drug tests and reference calls.

With an incomplete database, however, employers could be given "a false sense of security that somebody who may be really dangerous isn't, because their name isn't there," said Dr. Sidney M. Wolfe, director of Public Citizen's Health Research Group.

The federal government has had plenty of time to make it right, said Wolfe, whose Washington-based group advocates for patient safety. "It's really just embarrassing."