Leading US technology companies, including Amazon.com Inc., Anthropic, Apple Inc., Alphabet Inc.’s Google and OpenAI Inc., have pledged to work with health systems and the Trump administration to make the nation’s fragmented medical data more useful for patients and providers.The challenges of working with people’s private health information have created a black box around much of medicine. President Donald Trump and top health officials — including Centers for Medicare and Medicaid Services Adm...