Erin Dwyer has been doing a lot of waiting. After a sonogram in December, she found out that she has a growth on her right kidney and had to wait months to see a specialist. Now she’s waiting for a CT scan. When she called the radiologist’s office in early May to schedule it, “they were like, ‘OK, well, the earliest I can see you is like the first week of June,” said Dwyer, a graphic designer in Northern California. When she asked if they could possibly fit her in earlier, she said she was told: “‘There’s actually this shortage...