Abstract
Capsule Summary
Financial and administrative barriers, including lack of a physician work RVU for CPT 95044 and insurer caps on allergens, contribute to reluctance among ACDS members to administer patch testing.
Many providers are not compensated beyond evaluation and management codes and frequently write off costs, which reduces extended testing and Medicaid acceptance.
Standardized reimbursement models and clearer billing guidance may help support sustainable patch testing practices and improve patient access.
BACKGROUND
Allergic contact dermatitis (ACD) is a common inflammatory skin disease, with an estimated prevalence of 15–20% of the general population. 1 The gold standard for diagnosing ACD is the patch test. 2 The value of this diagnostic exam is that it allows providers to identify a precise cause of ACD, rather than guessing and removing potential culprits from a patient’s personal care routine. Despite the morbidity associated with ACD and the diagnostic utility of patch testing, it remains underutilized. In fact, 1 study estimated that about 1 in every 5 dermatologists never performs patch testing. 3 However, we believe this number may even be an underestimate, as this study was published in 2002 and is therefore unlikely to accurately reflect current trends in clinical practice. Moreover, a 2012 study demonstrated that a large percentage of residency programs do not have formal patch test training. 4 This dearth of residency training may contribute to a continued lack of comfort and familiarity with administering the test in clinical practice.
A key factor that contributes to the limited adoption of patch testing is its current reimbursement structure. In the United States, health care providers are reimbursed based on the relative value unit (RVU) system. RVUs are determined by the Centers for Medicare and Medicaid Services (CMS) and are a standardized metric used to measure the resource intensity of a medical service and to provide a metric for provider productivity and reimbursement. For each medical service provided, a payment formula contains 3 RVU components: there is 1 for practical expense (PE RVU), 1 for malpractice (mRVU), and 1 for physician work (wRVU). Patch testing is billed under CPT code 95044, which includes RVUs for practice expense and malpractice liability but not for a separately designed physician wRVU. As a result, providers are not directly reimbursed via a wRVU for the expertise required to perform and interpret the test, which may affect its perceived value within productivity-based compensation models. 5
In addition, there are differences in fixed costs for patch testing that can further impact its financial viability. The Thin-Layer Rapid Use Epicutaneous (TRUE) test has a set price that may exceed insurer reimbursement, potentially resulting in a net loss to the practice. While expanded patch testing may involve less expensive materials, the labor costs for preparing, applying, reading, and documenting results remain considerable and can impact profitability.
Moreover, CMS applies a Medically Unlikely Edit to CPT code 95044, limiting reimbursement to 90 units per day. 6 This national cap restricts the number of allergens that can be tested in a single session for Medicare patients, regardless of clinical indication, and may require providers to alter their testing protocols to remain compliant and avoid denied claims. To address these challenges, some institutions compensate patch testers via stipends or by allocating a percentage of patch testing collections.
Furthermore, variable reimbursement rates may make patch testing financially unfavorable for some payor types. At some institutions, providers are paid a stipend, while at others, providers are paid a percentage of billable collections. While existing practices may struggle to continue patch testing, these financial hurdles may present an insurmountable challenge to physicians wishing to integrate patch testing into their clinical practice. Herein, we present updated data regarding the current landscape of patch testing and patch test reimbursement in the United States.
METHODS
A survey composed of 19 multiple-choice questions and 1 open-ended question was emailed to all members of the ACDS between December 2024 and January 2025. Our survey gathered general information regarding provider specialty, location, and years in practice. It also asked survey respondents to report activity regarding extended patch testing, reimbursement policies, and practice patterns such as prior authorization, no-show policies, private insurance, and provider receptivity to Medicare/Medicaid. One open-ended question was available to allow respondents to elucidate specific concerns or difficulties they may have regarding the financial aspect of patch testing. Two team members (R.M. and W.L.) independently reviewed responses to the open-ended question to assess for common themes among the data. Themes were refined through group discussion and comparison of interpretations until consensus was reached regarding the final thematic framework. Survey data were tabulated using REDCap. This study was approved by the Northwestern University IRB.
RESULTS
Survey Respondent Demographics
The survey was distributed to 1076 recipients via the ACDS email listserv, yielding 76 responses from ACDS members (7.1% response rate). Of the respondents, 54% were female (n = 41), and 46% were male (n = 35) (Table 1). Regarding medical specialty, 82% (n = 62) were in dermatology, while 18% (n = 14) were allergists. The median number of years in practice among participants was 14, with a mean of 16.4 years (SD: 12.4 years). Regarding practice location, 51% (n = 39) were based in suburban areas, 43% (n = 33) in urban areas, and 5% (n = 4) in rural settings.
Demographics of Survey Participants
When categorized by practice type, 33% (n = 25) were affiliated with academic institutions, 28% (n = 21) worked in dermatology-only practices, 24% (n = 18) were part of multispecialty groups, 13% (n = 10) were in solo private practice, and 3% (n = 2) reported “other” practice types.
Variability in Reimbursement Models
To better understand existing reimbursement models and patch testing practices, we asked ACDS providers about how they are paid for patch testing and if their practice offers extended patch testing for patients (Table 2). Among the core allergen series used by respondents, the North American Contact Dermatitis Group (NACDG) series and the ACDS series were the most commonly selected, with only a small proportion using the TRUE test.
Overall, 42% of respondents (n = 32) stated that they never perform extended patch testing, and 29% of respondents (n = 22) reported that they sometimes perform extended patch testing. By reimbursement structures, 38% (n = 29) are paid for patch testing through a percent of collections, 41% (n = 31) are not paid beyond evaluation and management (E/M) codes, 3% (n = 2) are compensated via a yearly stipend. Among those who are paid by collections, the median collection rate was 45% (min: 35%, max: 55%).
Patch Testing Practices and Reimbursement Models of Participants
NACDG, North American Contact Dermatitis Group; TRUE, Thin-Layer Rapid Use Epicutaneous; ACDS, American Contact Dermatitis Society.
Provider Practice Patterns
Several questions were asked to assess differences in how providers structure their patch testing visits. 17% of respondents (n = 13) require patients to pay a deposit to reduce no-show occurrences, and 38% (n = 29) charge patients for no-showing for their patch testing appointment (Table 3). When assessing how providers manage daily/yearly patch testing caps, if a patient’s private insurance does not cover all of the patch testing, 53% of respondents (n = 40) stated that they write off the remaining balance, while 47% (n = 36) bill patients for the remaining balance.
Practice Patterns of Survey Participants
Regarding payor acceptance, 42% of respondents (n = 32) reported that they do not accept Medicaid. Medicare imposes a daily limit of 90 allergens and prohibits billing patients for any charges beyond the covered amount. When more than 90 allergens are needed, patch testing providers face logistical and financial challenges, as reflected in the survey results. Among respondents, if a Medicare patient needs more than 90 allergens, 30% apply all allergens on the same day and write off any remaining balance, while 18% require Medicare patients to come in on multiple days so as not to exceed the 90-allergen cap. Notably, 47% of respondents do not test more than 90 allergens among Medicare patients, and 3% do not accept Medicare.
Additional Challenges Involved in Patch Testing Reimbursement and Billing
An open-ended question allowed respondents to express additional concerns regarding the challenges they face in patch testing reimbursement. Individual responses were reviewed by authors R.M. and W.L. using an inductive thematic analysis to identify recurring patterns. Of the 30 open-ended responses, the most commonly cited problem was billing and current compensation models that limit the maximum number of patches a practice can apply per day. Many respondents express that patch testing is not financially viable, especially under current wRVU models for patch testing where a practice may not adequately reimburse a physician for the work they do. One respondent mentioned that academic hospital-based practices also face challenges as fees go to the hospital rather than to the specific provider. Additionally, insurance restrictions on the number of allergens tested make expanded patch testing difficult to conduct. Some providers bill for fewer allergens than they actually test, writing off the extra costs. Others appeal denials but find the process burdensome.
Moreover, there is widespread confusion regarding how to bill for placement, follow-up visits, and final readings for patch testing, as some respondents reported a lack of clear guidance. Some providers charge separately for counseling at the final visit, while others do not. Another challenge is the dearth of clear guidance as to whether E/M codes can be billed with patch testing visits.
Furthermore, respondents cited high no-show rates as particularly problematic given the multistep nature of patch testing. One respondent mentioned attempting to mitigate this problem by making a confirmation call 1 hour before a patient’s appointment before preparing patches, but missed visits still result in financial loss and scheduling inefficiencies. Moreover, many providers report financial losses when treating patients with Medicaid and Medicare, leading some physicians to limit the number of such patients they offer patch testing to. Some providers avoid insurance altogether, opting for flat fees for patch testing. High facility fees in academic centers, inconsistent reimbursement based on practice settings, and hospitals handling different payers with varying policies further complicate the billing landscape. Many respondents also advocate for expanded patch testing to improve ACD patient outcomes; however, challenges in reimbursement and daily insurance caps hinder its utilization.
The overall theme of the open-ended questionnaire is frustration regarding the current financial and administrative barriers that prevent comprehensive patch testing. These barriers may lead to missing relevant allergies and, ultimately, a negative impact on a patient’s quality of life.
DISCUSSION
This survey of 76 members of the ACDS highlights significant challenges in patch testing reimbursement, reflecting the most up-to-date clinical practice trends. While 38% were paid through a percentage of collections, 41% received E/M code compensation only, thus contributing to financial strain. Furthermore, insurance caps on the number of testable allergens forced many providers to either limit the number of tested allergens or write off the cost of allergens tested above a payor’s cap. To reduce the potential for losses, 38% charged patients for no-show appointments, and 17% required pre-appointment deposits. To help clinicians navigate these challenges, several practical strategies may support more sustainable patch testing practices, as summarized in Table 4. Overall, respondents expressed frustration with unclear billing guidelines and ongoing financial barriers that restrict comprehensive patch testing for their patients. While our findings highlight reimbursement as a key challenge, access is also influenced by other factors, including regional availability of trained providers and institutional support, 7 which were not directly captured in this survey.
Practical Recommendations for Optimizing Patch Testing Practice
ACDS, American Contact Dermatitis Society.
Patch testing is a vital diagnostic tool for ACD; yet, accessibility is currently hindered by financial and administrative barriers. Patch testing is time-intensive, requiring multiple, long visits. Our survey results underscore the need for standardized reimbursement models that adequately compensate physicians for the time and expertise required for patch testing. As demonstrated by the survey results, a substantial proportion of physician providers are either not compensated for patch testing beyond E/M codes or are reimbursed through inconsistent models such as a yearly stipend.
An additional level of complexity is payor mix. Traditionally, private insurers reimburse more than government programs, such as Medicare and Medicaid. These pressures are evident in our data, where a majority of respondents (58%) do not accept Medicaid. Our survey assessed how traditional Medicare patients are tested, but due to their complex, heterogeneous landscape, we did not ask about Medicare Advantage plans. In the experiences of author W.L., Medicare Advantage plans still maintain an 80-allergen daily cap, and appeals to test beyond the cap are never granted (unlike for traditional Medicare). These financial challenges may result in a delay or an inability of low-income or retired persons to receive patch testing.
Moreover, reimbursement limitations appear to significantly impact clinical decision-making among patch testing providers. In our sample, 42% of respondents (n = 32) reported not accepting Medicaid, likely reflecting historically low reimbursement rates that render the service financially unsustainable.8,9 Additionally, Medicare imposes a daily cap of 90 allergens and prohibits balance billing, preventing practices from charging patients for amounts not covered.6,10 These constraints may discourage providers from offering patch testing to publicly insured patients, potentially contributing to disparities in access.
Another added intricacy is that even among private insurers, reimbursement rates per patch may vary by state, and differences in daily testing caps may vary by insurance plan. Without a designated wRVU number, many physicians face financial disincentives that may contribute to their reluctance to perform patch testing, let alone perform more comprehensive, extended testing.
A 2018 survey study highlighted the compensation challenges associated with patch testing and noted that these obstacles may discourage providers from offering the service. 11 Because the data in that study were collected in 2016, nearly a decade before we collected our data, we sought to evaluate whether any improvements had occurred since then and broadened the scope by including allergists and private practice physicians, 2 groups not represented in the prior study. Since that time, the dermatology practice landscape has evolved in ways that may further complicate patch testing implementation. The rise of productivity-based compensation models, 12 increased enrollment in Medicare Advantage plans, 13 and recent changes to E/M coding in 2021 14 have introduced new administrative and financial pressures. While CPT code 95044 itself has not changed, these broader shifts may have amplified its limitations in current practice. Our findings capture these contemporary dynamics and incorporate perspectives from underrepresented practice settings.
Compared to general dermatology visits, patch testing visits are longer. As such, no-shows or last-minute cancellations have a disproportionate financial impact. Despite this fact, less than half of respondents charge patients deposits or for no-showing their visit. A frequent complaint expressed in the free response answer was that institutions will not allow patch testing physicians to charge these deposits/fees. Another expressed concern was that academic institutions charge facility fees. These fees are allocated to the practice rather than the provider, thereby disincentivizing physicians who work in these types of settings.
Limitations to this study include a small sample size and a 7.1% response rate, which may introduce nonresponse bias. However, low response rates are common in physician surveys and do not necessarily preclude meaningful insights, particularly when respondents are experienced and actively practicing clinicians. 15 Additionally, the survey was distributed exclusively to members of the ACDS, and it may not be representative of all dermatologists and allergists who perform patch testing; this exclusion may potentially omit a significant number of general dermatologists that conduct some form of patch testing but are not affiliated with the ACDS. In addition, the survey does not include objective financial data regarding net revenue and specific amounts of losses due to patch testing. Larger-scale projects that include quantitative data are warranted to further corroborate the findings of our survey.
CONCLUSION
To improve the availability and administration of patch testing, future efforts must focus on advocating for structured reimbursement models and tangible, equitable policies that acknowledge the complexity of patch testing. Standardizing billing practices, expanding the number of allergens covered by insurance, and addressing no-show challenges could help mitigate financial risks for providers and may increase patient access to accurate diagnoses and appropriate treatment, although additional structural barriers will need to be addressed in parallel.
Future initiatives by the ACDS could consider offering updated, practical guidelines on billing strategies to help physicians navigate patch testing challenges and advocate for sustainable reimbursement practices. As a leading organization in contact dermatitis, the ACDS is well positioned to provide ongoing educational and advocacy efforts that support consistent and appropriate reimbursement for patch testing services.