When Joe Graedon lost his mother in 1996 following a series of hospital errors, she became one of at least 500,000 people who die each year from such mistakes. So the pharmacologist and his medical anthropologist wife, Teresa, who host a public radio show and write a syndicated newspaper column called the “People’s Pharmacy,” turned their attention to patient safety in their latest book, “Top Screwups Doctors Make and How to Avoid Them,” ($26, Crown Archetype). We have some pointers for your next appointment.

Why is the No. 1 screwup “not listening to patients”?
TG: We assigned it the value of No. 1 because I think that a lot of the rest of the screwups that doctors make are related to poor communication, being in a hurry, not paying attention to what the patient has to say.

How can patients make sure they’re heard?
JG: It’s absolutely critical that there be verification. We liken this to the way in which pilots communicate with air-traffic controllers. Whenever an instruction is given from the control tower to a pilot, the pilot repeats it back.

TG: While ideally the doctor asks the question, the patient gives an answer and the doctor listens to the entire answer — and the patient has given the entire answer — we can’t assume that’s happening. If the doctor fails to ask or if the doctor interrupts, it is up to the patient to say, “There are just three other things that I wanted to say.”

So, bring a list of concerns to your appointment.
JG: It’s necessary but not sufficient. If you go with a list of 12 things, everything that’s been bothering you for the last six months, from the fact that you’ve been coughing up blood to the fact that you have athlete’s foot and it really itches and is keeping you awake at night, do not put athlete’s foot at the top of your list. Coughing up blood? No. 1. Your doctor only has seven minutes, maybe 10 at the most. Tell your physician, “These are the top three, four, five things that I’m really worried about.” Make every second count.

Which screwup is most surprising?
JG: I think it comes as a huge shock to people that doctors miss a diagnosis so frequently. [A Johns Hopkins patient safety expert estimates] that 40,000 to 80,000 people die every year from misdiagnosis in hospitals. That’s just in hospitals. If you add in nursing homes and outpatient facilities, every other setting where people have interaction with health care workers, the number is clearly way higher than that. We have data that between 10 and 15 percent of all diagnoses are wrong.

What do you do if you’re feeling uncomfortable about a diagnosis or prescription?
JG: If you feel you’re not getting high-quality care, you need to fire your doctor. We have the most radical tip on how to stop hospital screwups and that is “when in doubt, just say no.” Most people say no to their kids or the car salesman or almost anybody else, but when it comes to the hospital, to say no seems like an impossible challenge, and yet it is your most powerful ace in the hole. When you say no in the hospital, everything stops. It’s not “no” to be arbitrary. It’s to get an explanation.

TG: Say, “I need to understand what this is before I’ll agree to it.”

How do you choose a doctor?
TG: Interview the doctor as though you were interviewing a job applicant. You’ll have to pay for that time, but it will be so worth it.