The Department of Veterans Affairs' internal watchdog is probing manipulation of appointment data at 42 VA medical centers, up from 26 last week, it said in an interim report on allegations of secret waiting lists.
The office said it has confirmed that "inappropriate scheduling practices are systemic" throughout the Veterans Health Administration.
The report confirmed allegations that staff at VA medical facilities in Phoenix significantly understated months-long wait times for healthcare appointments for veterans. It linked these actions to performance appraisals, bonus awards and salary increases for VA executives.
The findings prompted some Republicans and Democrats who had withheld judgment on Shinseki to call for his immediate resignation.
"If Secretary Shinseki does not step down voluntarily, then I call on the president of the United States to relieve him of his duties," Republican Senator John McCain of Arizona told a news conference in Phoenix.
The scolding continued during a House Veterans Affairs Committee hearing on Wednesday night where three VA officials were asked to testify on the alleged existence and destruction of a secret wait list identified by whistleblowers in Phoenix.
Dr. Thomas Lynch, the agency's assistant deputy under secretary for health for clinical operations, said the waiting list was in fact an "interim work product" meant to hold names of veterans whose appointments had been cancelled. Lynch said that the list was properly destroyed after the patients were rescheduled to avoid keeping unnecessary information on patients.
His answer did not satisfy members of the committee, including Chairman Jeff Miller who has called for Shinseki's resignation and others who chastised the officials for being blind to the agency's problems.
"How you can stand in a mirror and look at yourself...and not throw up knowing that you've got people out there?" Congressman Phil Roe asked Lynch. "They're desperate to get in."
Shinseki, a retired four-star Army general, has headed the VA since early 2009. The inspector general said it has filed 18 reports on VA patient scheduling deficiencies since 2005.
In Phoenix, the inspector general said it identified 1,700 veterans who were waiting for a primary care appointment but who did not appear on the agency's electronic waiting list.
The inspector general said a sample of 226 veterans waited on average 115 days for their first primary care appointment at Phoenix-area clinics, far longer than the 26-day average reported by the Phoenix VA and the department's 14-day goal.
But the Inspector General's Office said it needed more information to determine whether the appointment delays resulted in delayed diagnosis or treatment, or any deaths. VA doctors in Phoenix have said some 40 veterans had died while waiting for care.
FINDINGS "TROUBLING," "REPREHENSIBLE"
President Barack Obama "found the findings extremely troubling," White House spokeswoman Jessica Santillo said, adding that the VA must take immediate steps to contact veterans waiting for care.
Last week Obama said Shinseki's job could be on the line depending on the investigation results.
Shinseki, in a statement, called the findings "reprehensible" and directed the Phoenix facility to "immediately triage" the veterans to get them care.
Shinseki is conducting his own review of scheduling practices at VA health care facilities nationwide, and was expected to deliver preliminary results from that effort to Obama this week.