KUSA — Starting in 2015, 9Wants to Know asked viewers to show them their most outrageous medical bills.

And ever since, Reporter Chris Vanderveen and Producer Katie Wilcox have highlighted some of the issues plaguing patients in the medical industry. Below, you’ll find some of their past coverage of the healthcare industry, which accounts for $1 in $5 spent in the U.S.

Here's a look at our coverage from the 9Wants to Know series, Lien on Me:

How you can visit the hospital, then get a lien on your home

A six-month investigation discovered common, emergency surgeries inside Denver-area hospitals that led to lawsuits, property liens and wage garnishments. Current Colorado law appears incapable of protecting patients from so-called surprise bills.

Why hospitals work with doctors who sue patients over medical bills

One of the nation's largest for-profit hospital providers told 9Wants to Know it is not the company's policy to place liens on property or garnish wages for payment of medical bills. But the doctors who work within the hospitals' walls may still do just that.

Why the law isn't protecting patients from surprise medical bills

As Colorado patients plead for more protection from surprise medical bills, the Colorado legislature can't seem to break free from grasp of well-funded special interests.

Ways to protect yourself from surprise medical bills

Patients left unprotected by current Colorado law and a nonexistent federal law must find ways to protect themselves from surprise medical bills.

As part of an ongoing 9Wants to Know investigation “Lien on Me,” it’s important for patients to know what they can do to lessen the chances of receiving a surprise medical bill that can stretch well into the thousands of dollars.

Here are our past stories:

10 patients, 10 stories of outrageous hospital bills

After hundreds of you sent us copies of your bills, 9Wants to Know investigated some common, and some shocking charges, in these patients’ medical bills.

How peeing in a cup can cost you $6,250

A different kind of gold rush has come to Colorado. 9Wants to Know found urine drug tests cost the state of Colorado’s Medicaid program more than $1 million in every month of 2016.

These medical bills actually got bigger once insurance was involved

Patients with health insurance are billed differently than those who don’t have insurance, and some of your bills showed us insurance doesn’t always guarantee the best deal.

Why visiting the ER cost so much money

The ER is one of the most expensive places a patient can go for care. 9Wants to Know read through dozens of medical bills and found out how hospitals were “coding” an ER visit, and why those codes can lead to thousands of dollars in charges.

How you could get a medical bill from someone you’ve never even met

A patient who goes to an in-network hospital for an emergency is supposed to be protected from getting out-of-network bills – but a “loophole” in a Colorado law has left patients vulnerable to paying hundred or even thousands to out-of-network doctors.

Why an ‘outrageous’ $169,000 medical bill actually got paid

A viewer sent us not a bill, but a check. A check they received from their insurance company that they were supposed to forward to an intraoperative neuromonitoring company. 9Wants to Know learned why this bill was paid, and who would receive the money.

How an investigation into freestanding ERs turned into so much more

9Wants to Know started asking viewers to show us your bills in 2015. By 2017, the series of stories and investigations had saved you more than $275,000.