Evaluation and demonstration of a new tuberculosis diagnostic tool for Indonesia: Study protocol of the EVIDENT cluster randomised controlled trial

Imagine the world of public health as a giant, bustling city where invisible invaders—tiny germs called Mycobacterium tuberculosis—are trying to sneak in and cause trouble. This germ causes a disease called Tuberculosis (TB), which is like a slow-burning fire in the lungs. For a long time, the only way to find these sneaky invaders was to ask people to cough up a thick, sticky substance called sputum (spit) from deep in their lungs. But here's the problem: not everyone can cough up enough spit, and some people just can't do it at all. It's like trying to find a lost key by only looking under the streetlamp where the light is good, even though you dropped it in the dark. If you can't get the sample, you can't find the germ, and the fire keeps burning, spreading to neighbors.

Now, scientists have been working on a new kind of "germ detector" that doesn't need a deep cough. They are testing a tool that can look at a simple swab of the tongue, which is much easier to get. This paper is about a massive experiment, or a "detective story," taking place in Indonesia to see if using this new tongue-swab tool, combined with a few other smart tricks, can help catch more of these invisible invaders and put out the fire faster. The researchers aren't just testing the tool in a lab; they are testing a whole new way of doing business in the community to make sure everyone gets checked.

The Big Experiment: Catching TB with a Tongue Swab

This paper describes the plan for a giant game of "spot the difference" called the EVIDENT trial, taking place in the Bandung District of Indonesia. The researchers are trying to solve a tricky puzzle: how do we find more people with Tuberculosis when many of them can't produce the traditional spit samples needed for testing?

The Setup: Two Teams, One Goal
Imagine the city of Bandung is split into 40 different neighborhoods, each centered around a community health center. The researchers are going to play a game of chance to decide which 20 neighborhoods get the "Super Team" treatment and which 20 stay with the "Standard Team."

• The Standard Team (Control): These neighborhoods keep doing what they've always done. They use the old rules for finding TB. The only thing they get is a quick refresher course on how to report cases, just to make sure everyone is on the same page.
• The Super Team (Intervention): These neighborhoods get a brand-new, multi-part toolkit designed to catch TB like a pro.

The Super Team's Toolkit
The "Super Team" gets four special upgrades working together:

1. The New Detective Tool (MiniDock MTB): Instead of just waiting for a cough, health workers in these neighborhoods get a new machine called the MiniDock MTB. This device can test for TB using a swab of the tongue if the patient can't cough up spit. If they can cough, they test the spit. If they can't, they test the tongue. It's like having a detective who can find clues on the floor or on the wall, not just one specific spot.
2. Smarter Rules (Clinical Algorithms): The doctors and nurses get a new playbook. It tells them exactly when to use the tongue swab, when to use the spit, and how to mix these new tests with other tools like chest X-rays to make the best decision.
3. The Hype Squad (Promotional Package): Since many people first go to pharmacies when they feel sick, the team trains pharmacy staff and other local workers to spot the signs of TB. They act like a referral network, telling anyone with a cough, "Hey, go to the health center to get checked with our new test!"
4. The Neighborhood Watch (Contact Investigation): Community volunteers, known as cadres, go into homes to check on the family members of anyone found to have TB. They bring the new testing tools right to the doorstep, making it easy for everyone to get tested without leaving their house.

What They Are Looking For
The main goal of this experiment is to see if the "Super Team" neighborhoods find and report more TB cases than the "Standard Team" neighborhoods. They aren't just counting how many people show up; they are counting how many new cases are discovered and officially reported to the government system.

They will also check:

• Are more cases being confirmed with a lab test (microbiologically confirmed) rather than just guessed?
• Is it taking less time for a patient to get a diagnosis?
• Are people visiting the clinic fewer times before finally getting a diagnosis?
• Does this new way cost more or less for the patients and the clinics?

The Rules of the Game
This isn't a quick test; it's a marathon. The researchers will watch these 40 neighborhoods for 12 months after the new tools are fully set up. They will compare the numbers from this year to the numbers from the year before the experiment started.

To make sure the results are fair, the researchers are using a special kind of math (a cluster randomised controlled trial) that treats each neighborhood as a single unit. They know that people might travel to different neighborhoods to get care, which could mix the results a little bit, so they are focusing their main score on the health centers themselves rather than just the people living in the area.

What They Expect to Find
Right now, this paper is the plan (the protocol) for the experiment. It hasn't finished yet! The researchers are currently in the middle of rolling out these tools. They expect that by using the tongue swab and the community volunteers, they will catch more TB cases that were previously slipping through the cracks.

If the "Super Team" neighborhoods end up with more diagnosed cases, it will prove that this whole package of new tools and community help works. This would be a huge win for Indonesia and other places with lots of TB, showing that we can find the disease faster and easier, even when people can't cough up a sample. But until the 12 months are up and the data is analyzed, the final answer remains a mystery waiting to be solved.