U.S. lawmaker calls for tech officials to testify about Obamacare WASHINGTON (Reuters) - U.S. officials who helped develop or oversee the rollout of the flawed Obamacare website will appear before the House of Representatives Oversight Committee next week, the panel's Republican chairman said on Thursday. Representative Darrell Issa said he wants to hear from these officials next Wednesday about why the website has performed so poorly, potentially preventing millions of people from enrolling in the new online health insurance exchanges. "When HealthCare.gov launched on October 1, testing was incomplete, the system had not yet been fully tested for security concerns and new problems kept appearing," said Issa, a Republican. "This hearing will ask top administration technology officials what went wrong, what they're doing to fix it, and whether recognized IT (information technology) best practices were really followed," he said. The officials due to appear include: Todd Park, chief technology officer at the White House; Steve VanRoekel, chief information officer at the White House; and Henry Chao, deputy chief information officer at the Centers for Medicare and Medicaid Services. Reporting By Karey Van Hall; Editing by Xavier Briand