Diagnostic access is a public health issue because millions of people cannot get the tests they need to detect serious illness—and when diagnosis is delayed or prevented entirely, people die from treatable conditions. Nearly one-fourth of U.S. adults with diabetes remain undiagnosed, meaning they don’t know they have the disease and can’t begin treatment. A woman in the UK might wait five or more years for a diagnosis of a condition that has been damaging her health the entire time. Nearly half the global population lacks access to the essential diagnostic tests that would identify disease early, when treatment is most effective. The barrier isn’t always ignorance.
Sometimes it’s cost: over 70 percent of insured patients in the U.S. encountered out-of-pocket expenses just for follow-up breast cancer diagnostic tests in 2023. Sometimes it’s geography: patients in North Dakota faced average out-of-pocket costs of 51.8 percent of the test price, while those in Delaware paid only 9 percent. Sometimes it’s capacity: primary care shortage areas in the U.S. affect 14 million Americans who simply have nowhere to go for basic diagnostic evaluation. The result is a healthcare system where access to diagnosis depends not on medical need, but on zip code, insurance status, and wealth.
Table of Contents
- THE SCALE OF UNDIAGNOSED DISEASE IN AMERICA
- THE COST BARRIER THAT PREVENTS DIAGNOSIS
- HOW DELAYS IN DIAGNOSIS AFFECT SURVIVAL AND OUTCOMES
- WHEN HEALTH SYSTEMS CANNOT MEET DIAGNOSTIC DEMAND
- GLOBAL INFRASTRUCTURE GAPS AND PERSISTENT INEQUITY
- TECHNOLOGY AND MARKET GROWTH HAVEN’T CLOSED THE ACCESS GAP
- WHAT RECENT POLICY CHANGES REVEAL ABOUT THE PRIORITY GAP
- Frequently Asked Questions
THE SCALE OF UNDIAGNOSED DISEASE IN AMERICA
The undiagnosed diabetes crisis illustrates the scope of the problem. An estimated 445 million adults aged 30 or older with diabetes worldwide were not receiving glucose-lowering treatment because their disease had never been diagnosed. In the United States alone, approximately 25 percent of adults with diabetes don’t know they have it. These aren’t people making a choice to avoid diagnosis; they are people whose disease remains invisible until it causes a complication—blindness, kidney failure, amputation, or stroke. The problem extends beyond diabetes.
Nearly 10 percent of women in the UK are currently living with an undiagnosed health condition, many of them having waited years for answers. For some women, the wait stretched beyond five years. During those years, the undiagnosed condition has continued to progress, often accumulating damage that becomes irreversible. A woman might attribute her fatigue to stress, her joint pain to aging, her cognitive changes to normal life. By the time she receives a diagnosis, the disease may have already crossed the line from treatable to chronic and degenerative.
THE COST BARRIER THAT PREVENTS DIAGNOSIS
insurance coverage doesn’t solve the diagnostic access problem because diagnostic testing carries significant out-of-pocket costs even for insured patients. In 2023, more than 70 percent of commercially insured patients in the United States who underwent follow-up breast cancer diagnostic testing faced out-of-pocket expenses. These weren’t routine screenings covered by insurance; they were the diagnostic tests that determined whether a suspicious finding was actually cancer. The cost of these tests—typically ranging from hundreds to thousands of dollars for multiple imaging studies and biopsies—delays or prevents many patients from completing the diagnostic process. Geographic disparities in cost create an unequal system where a patient’s location determines whether diagnosis is affordable. A woman in North Dakota faced an average out-of-pocket cost burden of 51.8 percent of the diagnostic test price, effectively making it nearly unaffordable for many families.
In contrast, women in Delaware paid only 9 percent out-of-pocket, and those in New York paid 12.9 percent. The same diagnostic test, ordered for the same medical reason, costs vastly different amounts depending on state-level insurance regulations and healthcare policies. The financial barrier is broad: nearly 40 percent of U.S. adults postponed or skipped needed medical treatment due to affordability concerns in 2024. When cost is a barrier to diagnosis, some patients make the decision to wait—hoping the symptoms resolve on their own, hoping they’ll find money later, hoping they’ll have insurance next year. What they’re doing, sometimes unknowingly, is allowing disease to progress without intervention.
HOW DELAYS IN DIAGNOSIS AFFECT SURVIVAL AND OUTCOMES
Delays in diagnosis are not benign delays. They are measured in lives lost. In cancer, a one-month delay in surgery after diagnosis results in a 6 to 8 percent increase in the risk of death. That means a patient who waits four months because of diagnostic bottleneck faces a 24 to 32 percent increased mortality risk compared to someone diagnosed and treated immediately.
The delay might result from a long wait for imaging, or a referral denial, or the patient’s inability to afford a diagnostic test. The mortality impact of delayed diagnosis appears across multiple conditions. In hemorrhagic fever cases—rare but severe infections—delayed diagnosis was linked to an adjusted odds ratio of 5.60 in a 2025 study, meaning patients who experienced diagnostic delay had more than five times the mortality risk compared to those diagnosed promptly. Delayed diagnosis of venous thromboembolism, blood clots that can cause sudden death, similarly increases mortality risk. These are not diseases where a few extra days or weeks are harmless; the diagnostic window is compressed, and delay becomes a risk factor for death.
WHEN HEALTH SYSTEMS CANNOT MEET DIAGNOSTIC DEMAND
The barriers to diagnostic access operate at the system level, beyond individual patients. Health systems face three major structural barriers: limited access to diagnostic technologies, limited familiarity among health workers with diagnostic devices, and low public awareness of diseases requiring diagnosis. These barriers overlap and reinforce each other. A rural hospital might have the budget to purchase one diagnostic machine, but no staff member has been trained to operate it. A clinic in a low-income area might have outdated equipment that breaks down because maintenance budgets don’t exist. A patient might not recognize their symptoms as requiring diagnostic evaluation because no community health campaign has raised awareness of the disease. Administrative bottlenecks compound the problem.
Sixty percent of U.S. patients reported facing administrative barriers including denied claims or referral denials—bureaucratic obstacles that prevented them from reaching diagnostic testing even when they were insured and their doctors had ordered the tests. These denials sometimes reverse on appeal, but while the appeal is pending, the diagnostic window closes. A patient suspected of having heart disease must wait weeks for insurance to approve an advanced imaging study; during that wait, the heart condition progresses. The workforce capacity crisis is particularly acute in public health infrastructure. Approximately 3,000 CDC employees departed since early 2025, including laboratory scientists and epidemiologists essential to testing operations and outbreak detection. As the CDC reviewed its portfolio of more than 500 diagnostic tests, it found itself considering discontinuing some tests—not because better alternatives exist, but because the agency lacked the staffing to maintain them. Some of these tests will be available through state laboratories or commercial providers, but that transition leaves gaps in coverage during the transition period and in regions where no alternative provider exists.
GLOBAL INFRASTRUCTURE GAPS AND PERSISTENT INEQUITY
Globally, diagnostic infrastructure is unevenly distributed. The median availability of essential diagnostics shows the inequality: basic diagnostics are available in 19.1 percent of primary care facilities, advanced primary care diagnostics in 49.2 percent, and hospital-level diagnostics in 68.4 percent. That median masks enormous variation by region and country. Sub-Saharan Africa has received significant investment in diagnostics, but the investment has been heavily weighted toward HIV, TB, and malaria—the diseases that attracted international funding.
A patient in Sub-Saharan Africa with a rare neurological condition or autoimmune disease may have no access to diagnostic testing at all because the infrastructure was designed for only three diseases. This creates a dangerous inequity where global diagnostic capacity is allocated not by medical need, but by which diseases are globally funded and which are not. A woman in a rural area of West Africa with symptoms of a thyroid disorder has no access to thyroid function testing. A child with symptoms suggesting lymphoma has no access to imaging or biopsy. Even when a patient can travel to a regional hospital, the diagnostic technologies available there are limited to the conditions that donors have funded testing for.
TECHNOLOGY AND MARKET GROWTH HAVEN’T CLOSED THE ACCESS GAP
The diagnostic market is growing rapidly. The global infectious diseases diagnostics market is estimated to grow from US$29.2 billion in 2026 to US$50.0 billion by 2033, representing a compound annual growth rate of 8.0 percent. The point-of-care diagnostics market alone, valued at approximately USD 53 billion in 2024, is projected to nearly double by 2033. New technologies are being cleared by regulators: in September 2025, QIAGEN received FDA clearance for the QIAstat Dx Rise syndromic testing system, which enables higher-throughput rapid infectious disease testing.
These are genuine advances in diagnostic capability. Yet market growth and technological advancement don’t automatically translate to access for patients who can’t afford tests or whose healthcare systems lack the infrastructure to implement new technologies. A new diagnostic test cleared by the FDA might be available only through expensive commercial labs in urban centers. A point-of-care test might be cost-effective in wealthy countries but unaffordable in low-income settings. The market is growing fastest in the most profitable segments, which typically means advanced diagnostics in wealthy countries, not the basic diagnostics that would help diagnose disease in low-resource settings.
WHAT RECENT POLICY CHANGES REVEAL ABOUT THE PRIORITY GAP
Policy changes in 2025 reveal that diagnostic access is increasingly recognized as a public health problem, but the solutions remain incomplete. The World Health Assembly passed a resolution in 2025 recommending that countries establish national diagnostics strategies and extend essential diagnostic services for both infectious and non-infectious diseases. This is significant because for decades, diagnostic strategy was not standardized internationally; countries operated without national diagnostic plans. The assembly’s action signals that diagnostic access is now recognized as foundational to public health, not peripheral to it.
Oregon became the first U.S. state to eliminate out-of-pocket costs for supplemental cervical cancer screenings, effective in the 2025/2026 legislative session, recognizing that cost barriers prevent women from completing the diagnostic process after an abnormal screening. This policy removes one specific financial barrier for one specific diagnostic test in one state, but it also reveals the fragmentation of the U.S. system: the fact that this is considered significant and unusual policy innovation indicates how pervasive the cost barrier remains. An independent assessment by the International Pandemic Preparedness Secretariat in 2025 identified persistent barriers in diagnostic preparedness across more than 100 countries, finding that most nations lack the testing capacity, trained workforce, and equitable access needed to detect and respond to emerging disease threats.
Frequently Asked Questions
Why is diagnostic access harder in rural areas?
Rural areas typically have fewer hospitals, clinics, and specialists. A patient in a primary care shortage area may need to travel hours for diagnostic testing. Additionally, rural healthcare facilities have smaller budgets and less ability to maintain specialized diagnostic equipment. The 14 million Americans living in primary care shortage areas often face both distance and limited availability as barriers to diagnosis.
Does having insurance mean I’ll have access to diagnostic testing?
Insurance covers diagnostic testing, but not the out-of-pocket costs associated with it. Over 70 percent of insured patients faced out-of-pocket expenses for breast cancer diagnostic tests in 2023. Your actual out-of-pocket cost depends on your specific plan, your state’s insurance regulations, and the test ordered.
How much does a diagnostic delay actually matter?
In cancer, a one-month delay in surgery increases mortality risk by 6 to 8 percent. For some infections like hemorrhagic fever, delayed diagnosis increases mortality risk by more than 500 percent. The time window between when disease is detectable and when treatment is most effective is compressed—delays matter.
Are new diagnostic technologies making testing more accessible?
New technologies are being developed and cleared for use, and the diagnostic market is growing. However, market growth doesn’t automatically mean better access for patients who lack affordability or infrastructure. New tests may be available only in major medical centers or through expensive commercial labs, potentially widening the gap between wealthy and low-resource settings.
What’s the difference between screening and diagnosis?
Screening identifies people who might have disease (usually through a simple, inexpensive test in a large population). Diagnosis confirms whether disease is actually present (usually through more specialized, expensive testing). Many people complete screening but never complete diagnosis because of cost or system barriers.
Is the U.S. diagnostic system better than other countries?
The U.S. has advanced diagnostic technology and capacity in wealthy urban areas, but also faces significant barriers including cost, administrative denials, and geographic inequality. Other countries have different barriers: less advanced technology but sometimes more equitable access to basic testing. No country has solved diagnostic access perfectly.
