A police investigation into a complaint that a staff member sexually abused a patient at a Halifax hospital was dropped because of a lack of evidence, a health official says.

Donna Dill, director of monitoring and evaluation in Nova Scotia's continuing care division, said the complaint involved an adult patient at the IWK Health Centre, and not a patient at the Capital District Health Authority as first believed.

Dill blamed the confusion on a clerical error.

The alleged case of sexual abuse was one of three initially investigated by the health department but passed on to police in the early stages of investigation.

The information was contained in a database obtained by CBC News through requests under provincial access to information legislation.

Health officials received more than 250 complaints from the fall of 2007 to last October, the first period that managers and staff of continuing care facilities were required to report all abuse complaints.

In about 40 of these cases, officials confirmed some kind of physical, emotional, sexual or financial abuse.

Dill wouldn't say what kind of disciplinary action has been taken.

"I know there have been some dismissals, but I couldn't tell you how many, either. That is not a role of the Department of Health," Dill said.

Though the department confirmed two cases of sexual abuse between Oct. 1, 2007, and Sept. 30, 2008, three more investigations of alleged sexual abuse were forwarded to police.

On May 23, a complaint was filed alleging a staff member sexually abused an adult patient at the IWK Health Centre, the children's hospital for the Maritimes. A Health Department investigator started to look into the matter but quickly called police.

Dill said police told her there wasn't evidence of criminal wrongdoing, so the complaint was dropped.

The other two cases involved allegations of residents abusing residents.

Dill said one case was dismissed following an investigation. She wasn't sure what happened with the other one.

The search of the database also uncovered an additional allegation of financial abuse against a nursing home resident that was sent to police before the Health Department investigation was complete.

Dill declined to comment, saying she can't talk about specific cases.

Maureen MacDonald, the New Democrat MLA who sponsored the Protection of Persons in Care Act, said the Health Department should be telling the public more.

"A reasonable person would want to have a reasonable amount of information to be able to feel that the purpose of the act is being achieved," MacDonald said. "I would like to see more transparency."

Dill said investigations of abuse at nursing homes could eventually be published on a provincial website.

But she said she believes the system as it exists now will prevent future cases of abuse.

With files from The Canadian Press