For the past 15 months, I’ve asked Vox readers to submit emergency room bills to our database. I’ve read lots of those medical bills — 1,182 of them, to be exact.

My initial goal was to get a sense of how unpredictable and costly ER billing is across the country. There are millions of emergency room visits every year, making it one of the more frequent ways we interact with our health care system — and a good window into the health costs squeezing consumers today.

I started my project focused on one specific charge: the facility fee. I found this charge for walking through an emergency room’s doors could be as low as $533 or well over $3,000, depending on which hospital a patient visited and how severe her case was. I also learned that the price of this charge had skyrocketed in recent years, increasing much faster than other medical prices for no clear reason.

But given the volume and diversity of bills I received, I’ve learned so much more.

I’ve read emergency room bills from all 50 states and the District of Columbia. I’ve looked at bills from big cities and from rural areas, from patients who are babies and patients who are elderly. I’ve even submitted one of my own emergency room bills for an unexpected visit this past summer.

Some of the patients I read about come in for the reasons you’d expect: a car accident, pains that could indicate appendicitis or a heart attack, or because the ER was the only place open that night or weekend.

Some come in for reasons you’d never expect. Like the little girl who swallowed a coin to hide it from her sister, the 12-year-old boy who was hit by a home run ball at a professional baseball game (who, incidentally, was given a $60 ibuprofen at the local children’s hospital), and the adult who ate an entire bag of chocolate candy … without realizing it was edible marijuana. Rest assured, they are all fine!

In so many ways, patients find themselves in a vulnerable position during these encounters with the health care system. The result is often high — and unpredictable — bills. Hospitals are not transparent about the cost of their services, their prices vary wildly from one ER to another, and it’s hard to tell which doctors are covered by insurance (even if the hospital itself is covered). In many cases, patients can’t be certain what they owe until they receive a bill in the mail, sometimes weeks or months later.

I’ve also learned that there is a lot of interest in fixing these types of situations. Since we started this project, multiple senators have introduced bills to prevent surprise emergency room bills — including one directly inspired by our project.

I’ll stop collecting emergency room bills on December 31. But before I do that, I wanted to share the five key things I’ve learned in my year-long stint as a medical bills collector.

1) The prices are high — even for things you can buy in a drugstore

One bill that left an impression on me came from a woman seen in the emergency room the day after her wedding. Her eye was irritated from the fake eyelashes she’d worn the night before, and she worried that her cornea might have been scratched.

The providers checked out her eye, squeezed in some eyedrops, and sent her home. She later got a bill that charged $238 for those eyedrops, a generic drug called ofloxacin. According to GoodRX, a website that tracks drug prices, an entire vial of this drug can be purchased at a retail pharmacy for between $15 and $50.

This is something that I saw over and over again reading emergency room bills: high prices for items that a patient could have picked up at a drugstore.

I see this a lot, for example, with pregnancy tests. They happen in emergency rooms for good reason: Doctors often need to know whether a woman is pregnant to determine her course of care. But the prices I’ve seen for pregnancy tests are really high.

The bills in our database include a $236 pregnancy test delivered in Texas, a $147 pregnancy test in Illinois, and a $111 test in California. The highest price I saw? A $465 pregnancy test at a Georgia emergency room. For that amount, you could buy 84 First Response tests on Amazon.

Or look at the price of a common antibiotic ointment called bacitracin (you might know it better by its brand name, Neosporin). The bills in our database show that one hospital in Tennessee charged a patient a pretty reasonable $1 for bacitracin — while another hospital in Seattle charged $76 for the exact same ointment. Since prices aren’t made public, it was impossible for these (or any) patients to know whether they were at a hospital that charges $1 for a squirt of antibiotic ointment or one that charges 76 times that amount.

These bills submitted to our database were in situations where there was not a life-threatening emergency, where a provider presumably could have sent the patient to a place where their drug is available cheaper, often over the counter. But that doesn’t seem to happen. Perhaps emergency room providers don’t know the price of the care they provide, either. Instead, patients are getting drugstore items in the emergency room at a significant markup — and paying higher bills as a result.

2) Going to an in-network hospital doesn’t mean you’ll be seen by in-network doctors

On January 28, 34-year-old Scott Kohan woke up in an emergency room in downtown Austin, Texas, with his jaw broken in two places, the result of a violent attack the night before. Witnesses called 911, which dispatched an ambulance that brought him to the hospital while he was unconscious.

Kohan, who submitted his bill to our database, ended up needing emergency jaw surgery. The hospital where he was seen was in network; he Googled this on his phone right after regaining consciousness. But the jaw surgeon who saw him wasn’t. Kohan ended up with a $7,924 bill from the surgeon, which was only reversed after I wrote about his bill in May.

Kohan’s case is something I see regularly in our database: patients who end up with big bills because they went to an in-network hospital but were seen by an out-of-network doctor.

Here’s how that happens: When doctors and hospitals join a given health insurance plan’s network, they agree to specific rates for their services, including everything from a routine physical to a complex surgery.

Doctors typically end up out of network when they can’t come to that agreement — when they think the insurance plan is offering rates that are too low but the insurer argues that the doctor’s prices are simply too high.

Unless states have laws regulating out-of-network billing — and most don’t — patients often end up stuck in the middle of these contract disputes.

Academic research has shown that most of these types of bills actually originate from a small number of hospitals.

These bills “aren’t randomly sprinkled throughout the nation’s hospitals,” one New York Times article from July 2017 noted. “They come mostly from a select group of E.R. doctors at particular hospitals. At about 15 percent of the hospitals, out-of-network rates were over 80 percent, the study found.”

These surprise bills appear to be especially common in Texas, where Kohan lives. As many as 34 percent of emergency room visits lead to out-of-network bills in Texas — way above the national average of 20 percent.

And, much like the bills with high prices, these bills are really hard to prevent. Out-of-network doctors won’t often mention that they don’t accept the patient’s insurance; they might not even know. And patients often have little choice about where to receive their care — like Kohan, who needed emergency jaw surgery due to his attack.

3) You can be charged just for sitting in a waiting room

Before I started reporting this project, I knew from my decade as a health care reporter that America has sky-high medical prices. But what I didn’t know was that patients can face steep bills even if they don’t see a doctor or have their ailment treated. They can decline treatment and still end up with a hefty fee.

I learned about this from a bill sent to me by Jessica Pell. She told me about going to an emergency room in New Jersey after she fell and cut her ear. She was given an ice pack but no other treatment. She never received a diagnosis. But she did get a bill for $5,751.

“It’s for the ice pack and the bandage,” Pell said of the fee. “That is the only tangible thing they could bill me for.”

After I saw Pell’s bill, I started looking through our database and finding similar bills from other patients. They all ended up with significant medical bills, in the hundreds or thousands of dollars. These fees were often on top of additional fees from another health care provider where they ultimately did receive treatment.

This is all due to the key fee I’ve been investigating this year: the ER facility fee. This is the fee that ERs charge for walking in the door and seeking care, something akin to a cover charge at a bar.

Hospital executives often argue that these fees help them keep the lights on and doors open for whatever emergency might come in, anything from a stubbed toe to a stroke patient.

But experts who study emergency billing question how these fees are set and charged, noting that they are seemingly arbitrary, varying widely from one hospital to another. A Vox analysis of these fees, published last year, shows that the prices rose 89 percent between 2009 and 2015 — rising twice as fast as overall health care prices.

“It is having a dramatic effect on what people spend in a hospital setting,” says Niall Brennan, the executive director of the Health Care Cost Institute, which provided the data for that analysis. “And as we know, that has a trickle-down effect on premiums and benefits.”

4) It is really hard for patients to advocate for themselves in an emergency room setting

Since I started working on this project, one of the questions I get most frequently is: How do I avoid a surprise ER bill? Or how can I get my ER bill lowered?

I wish I had a good answer, but I don’t. Patients are usually at the mercy of the hospital when it comes to ER billing.

I have talked to some patients who have successfully negotiated down their emergency room bills. Most of those people applied for financial aid, requested a prompt pay discount, or found an error on their bill.

Some especially savvy patients have even had luck arguing that their facility fee charge was coded incorrectly — that the hospital used a billing code that should be reserved for really intense, complex visits when their visit was actually pretty simple. I’ve noticed that these patients tend to have a doctor in their family who can help them make this type of argument.

Most patients who have successfully negotiated down a bill tell me it wasn’t easy. Erin Floyd from Florida told me about her experience reducing two of her daughter’s bills — one by 90 percent and one by 45 percent — through a combination of financial aid and prompt care discounts.

On the one hand, she was happy to have the bills lowered. In total, she ended up saving $4,369. On the other hand, the whole process was exhausting. There were lots of phone calls and faxes involved.

“I spent at least three hours on the phone working on this,” she says. “I was scanning, faxing, emailing, all while I was at work.” Over email, she described it as an “incredibly stressful and long process.”

And then there are, as Slate has noted, patients who have had their bills reversed after journalists wrote about them. Our project, for example, has resulted in $45,107 in medical bills being reversed after Vox began inquiring about those charges.

But for all of investigative journalism’s merits, reporters writing about medical bills isn’t a great solution for the health care system’s woes.

What stands out to me is that in all these cases, it’s essentially the hospital that gets to decide whether it wants to negotiate or reverse a bill. And if a hospital says no? If it won’t change the facility fee code, or doesn’t offer a prompt payment discount? The patient is essentially stuck. The hospital has the trump card: It can send the bill to a collection agency, a move that could devastate a patient’s credit. In those situations, there isn’t anything a patient can do to stop them.

5) Congress wants to do something about the issue

As more journalists write about ER bills, there is a growing outcry on Capitol Hill — and more senators on both sides of the aisle who want to do something about it.

There are now two proposals in Congress that would make the types of bills I write about a thing of the past. One comes from Sen. Maggie Hassan (D-NH) and another from a bipartisan group of senators including Sens. Bill Cassidy (R-LA) and Claire McCaskill (D-MO).

While the two bills aim to do the same thing (prevent surprise bills in the emergency room), they take different policy approaches. The Cassidy-McCaskill proposal essentially bars out-of-network providers from billing patients directly. Instead, they would have to seek payment from the health insurer, who would be required to pay a price similar to local market rates. (I’ve written in greater detail about how this works.)

Will either of these bills become law? It’s hard to tell. On the one hand, the safest bet with Congress is often inaction. But this issue seems to be gaining momentum. Just this week, for example, a large coalition of health plans and consumer advocates put out a statement supporting federal action on the issue. What’s more, there is bipartisan interest in working on this — making it the rare issue that just might bring Democrats and Republicans together on health care.

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