People receiving suspicious telephone calls trying to make medical appointments at their home should call the police, says Hastings Health Centre director Colin Dykes.
A "very astute" practice nurse received two phone calls from separate people on the same day last week, regarding calls from Niagara Healthcare, Dr Dykes said.
"They wanted to make an appointment with them in their home to show them something they said was beneficial for their health.
"The practice nurse contacted our manger and Googled Niagara, finding news items dating back to 2011 saying the company targeted the elderly offering home visits.
"A warning has been given to all general practices in Hawke's Bay regarding this organisation.
"People have been instructed to contact the police if they receive any of these phone calls and are concerned it is suspicious."
Health Hawke's Bay chief executive Liz Stockley said people should research to see if callers were genuine.
"The best organisation to contact is your family doctor to check the call out," she said.
"If the doctor has referred them to any service, such as Arthritis New Zealand, then they would be able to confirm that."
Media reports from 2011 state Niagara Healthcare targeted elderly people, offering home visits where a $1600 machine was demonstrated.
Niagara Healthcare manager Steve Oughton said his company used a professional call centre. "These girls are totally trained," he said.
"They really state what Niagara Healthcare is and how long we have been in business for - 65-plus years."
He said the business did little cold calling in Hawke's Bay but did make calls to people after being referred by clients.
He would follow up any complaints if people misunderstood the callers, he said.