---
title: Cut the out-of-pocket cost of an MRI and almost everyone wants one — including for the headaches that do not need it
publication: Medical Insights Korea
section: news
category: Screening
canonical_url: https://medicalinsightskorea.com/news/korea-low-value-mri-out-of-pocket-cost-vignette
author: Catherine Cho
published: 2026-09-16T09:00:00+09:00
modified: 2026-09-16T09:00:00+09:00
content_type: reporting
license: Quotation permitted with attribution to Medical Insights Korea and a link to the canonical URL.
---

# Cut the out-of-pocket cost of an MRI and almost everyone wants one — including for the headaches that do not need it

A Korean vignette study of 1,229 people found willingness to use a low-value MRI rising from around a third to nearly all once the price fell. The inequality in who used it narrowed, because everyone converged on the test that does not help.

## Answer

In an experimental vignette survey of 1,229 Koreans presented with uncomplicated headache and non-specific low back pain, willingness to use magnetic resonance imaging that guidelines classify as low-value rose from 36.7 to 49.6 percent in the lowest income quintile before out-of-pocket payment reduction to 89.8 to 98.0 percent for low back pain and 78.1 to 90.3 percent for headache across all income quintiles afterwards, and inequality between income groups narrowed — because the convergence was on using a test that does not benefit the patient.

## Key takeaways

- An experimental vignette survey used a proportional quota-based sample of 1,229 people in Korea, presenting hypothetical uncomplicated headache and non-specific low back pain.
- Before out-of-pocket payment reduction, the lowest income quintile was least likely to say they would use a low-value MRI: 36.7 to 49.6 percent for low back pain and 30.5 to 39.3 percent for headache.
- After out-of-pocket payment reduction, willingness reached 89.8 to 98.0 percent for low back pain and 78.1 to 90.3 percent for headache in every income quintile.
- Absolute and relative inequality in potential low-value MRI use fell after the price reduction: the slope index of inequality for low back pain dropped from 8.15 to 5.37 percent and for headache from 6.99 to 0.83 percent.
- Half of participants saw vignettes that included a physician recommendation for the low-value test, and the price effect appeared with or without that recommendation.
- Uncomplicated headache and non-specific low back pain are the standard textbook examples of imaging that guidelines advise against in the absence of red flags.

## Full article

Korean health policy has spent a decade extending insurance coverage to services patients previously paid for themselves, magnetic resonance imaging among them. The intended effect is that people who need a scan are not deterred by its price. A study designed to test the unintended effect asked a narrower question: what happens to demand for the scans that were never indicated?

### How the question was put

Published in the Journal of Preventive Medicine and Public Health, the study surveyed a proportional quota-based sample of 1,229 people in Korea using two hypothetical scenarios: uncomplicated headache, and non-specific low back pain. Both are standard examples of situations in which clinical guidelines advise against imaging when there are no warning features. Participants were asked whether they would be willing to have an MRI, before and after a reduction in what they would pay out of pocket.

Half of the participants first saw a version of the vignette that included a physician recommending the scan, so that the effect of price could be separated from the effect of a doctor's suggestion.

**Willingness to use low-value MRI, before and after out-of-pocket payment reduction**

| Scenario | Lowest income quintile, before | All quintiles, after |
| --- | --- | --- |
| Non-specific low back pain | 36.7–49.6% | 89.8–98.0% |
| Uncomplicated headache | 30.5–39.3% | 78.1–90.3% |

### The equality result, read properly

Before the price fell, income predicted willingness: the poorest quintile was the least likely to say they would have the scan. After it fell, that gradient largely disappeared. The slope index of inequality for low back pain fell from 8.15 to 5.37 percent, and for headache from 6.99 to 0.83 percent. The relative index moved from 1.20 to 1.06 and from 1.20 to 1.01 respectively.

**6.99% → 0.83%** — slope index of inequality in willingness to use low-value MRI for uncomplicated headache, before and after out-of-pocket payment reduction  
_Source: Shin Y, Lee JS, Do YK, Journal of Preventive Medicine and Public Health, 2022_

> **Equal access to a test that does not help is not an equity gain**  
> Falling inequality is normally the point of reducing what patients pay. Here the metric improves because every income group converges on wanting a scan that guidelines say should not be done. The poorest quintile's earlier reluctance was not underuse being corrected; on the study's own framing it was the group least exposed to a low-value intervention becoming as exposed as everybody else. An equity measure that improves when a harm is distributed evenly is measuring the wrong thing.

### Why low-value imaging is not merely a waste of money

MRI delivers no ionising radiation, so the cost of a low-value scan is not the cost of a low-value CT. What it shares with every other broad look at a person who is well is the finding nobody was seeking. In a German population cohort, disclosing incidental findings from whole-body MRI raised the rate of biopsies that returned nothing malignant by more than it raised the rate returning cancer.

A scan of a normal lumbar spine in a middle-aged adult reliably shows disc degeneration, bulges and facet arthropathy, because those are near-universal with age. Naming them on a report in a patient with non-specific back pain converts an ordinary symptom into a structural diagnosis, and the literature on what follows — further imaging, injections, referral — is the reason guidelines say not to look.

### What a vignette study can and cannot support

These are stated intentions, not scans that happened. People asked hypothetically what they would do systematically differ from people in a consulting room, and the study measures potential utilisation rather than utilisation. It also cannot capture the other half of the transaction: a scan requires a doctor to order it, and physician behaviour under changed reimbursement is not what was surveyed.

What it does establish is a price elasticity for a service where price was the main brake. Whatever restraint existed in the lowest income quintile was financial, and removing the finance removed the restraint. Policies that expand coverage without a parallel mechanism for distinguishing indicated from unindicated use are, on this evidence, expanding both.

## Sources

- Shin Y, Lee JS, Do YK. Increase in potential low-value magnetic resonance imaging utilization due to out-of-pocket payment reduction across income groups in Korea: an experimental vignette study. Journal of Preventive Medicine and Public Health 2022;55(4):389-397. doi:10.3961/jpmph.22.208. PMID:35940194. https://doi.org/10.3961/jpmph.22.208
- Richter A, Sierocinski E, Singer S, Bülow R, Hackmann C, Chenot JF, Schmidt CO. The effects of incidental findings from whole-body MRI on the frequency of biopsies and detected malignancies or benign conditions in a general population cohort study. European Journal of Epidemiology 2020;35(10):925-935. doi:10.1007/s10654-020-00679-4. PMID:32860149. https://doi.org/10.1007/s10654-020-00679-4

## Citation

Catherine Cho (2026). "Cut the out-of-pocket cost of an MRI and almost everyone wants one — including for the headaches that do not need it". Medical Insights Korea. https://medicalinsightskorea.com/news/korea-low-value-mri-out-of-pocket-cost-vignette

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