Two-thirds of U.S. doctors age 40 and under believe a fully connected healthcare environment will be achieved within the next five years. For those over 40, though, the proportion falls to 39 percent?and they just might be laughing at the younger generation's naiveté. That's one of my takeaways from a new study by MedData Group, a healthcare marketing company based in Topsfield, MA. The report surveyed 171 physicians across specialties and practices in February. We've previously written about the firm's surveys of mobile health adoption and doctors' opinions on the future of connected health.