Economic Evaluation of the Merit-Based Incentive Payment System for Ophthalmologists

This economic evaluation assesses US Medicare & Medicaid Services’ Merit-Based Incentive Payment System scoring and reporting for ophthalmologists.

Key Points

Question

What were the Merit-Based Incentive Payment System (MIPS) scores for ophthalmologists by filing category?

Findings

In this economic evaluation of 13 621 participating ophthalmologists, 92.9% (12 659) met criteria for positive payment adjustment. Individuals were less likely to achieve exceptional performance scores compared with participants filing as advanced alternative payment models (APMs) or group; for 78.4% of ophthalmologists (8777 of 11 193) achieving exceptional MIPS scores, mean (SD) annual adjustments were $244.60 ($217.36) to $4864.78 ($4323.08) per physician.

Meaning

Results showed an association between filing as group or APM with exceptional MIPS scores, suggesting that ophthalmologists filing as individuals should consider alternative filing approaches; changes in MIPS methodology may disproportionately affect certain ophthalmologists, which may warrant further study.

Abstract

Importance

The Merit-Based Incentive Payment System (MIPS) is intended to promote high-value health care through quality-related Medicare payment adjustments.

Objective

To assess the economic evaluation of MIPS scoring and reporting on ophthalmologists.

Design, Setting, and Participants

In this retrospective, cross-sectional, multicenter economic evaluation conducted from October 10 to November 30, 2021, MIPS performance and related payment adjustments were evaluated using the US Centers for Medicare & Medicaid Service (CMS) public data files for ophthalmologists. Participants were stratified by reporting affiliation. Analysis of variance and summary statistics were used to characterize and compare total and subcategory MIPS scores and adjustments received by participants. Reported CMS methodology and performance year (PY) 2019 payment percentages were used to estimate payment adjustments for the following categories: positive MIPS adjustment plus potential additional adjustment for exceptional performance, positive MIPS adjustment, neutral payment adjustment, negative MIPS payment adjustment, and maximum negative MIPS payment adjustment. Study participants included ophthalmologists registered for Medicare Part B with participation in the Quality Payment Program (QPP) in PY 2019.

Main Outcomes and Measures

Proportion of ophthalmologists qualifying for payment adjustments and payment adjustments.

Results

For PY 2019, 76.5% of ophthalmologists (13 621) who registered for Medicare participated in the MIPS pathway of the QPP. Ophthalmologists practiced in a predominantly large metropolitan area (12 302; 90.3%). Roughly 99% of participants (11 182) received nonnegative reimbursement adjustments, and 92.6% (10 367) received positive adjustments. Ophthalmologists filing as individuals were less likely to achieve exceptional performance scores compared with those who had a filing category of advanced alternative payment model (APM; odds ratio [OR], 0.0003; 95% CI, 0.00002-0.00481) or group (OR, 0.21013; 95% CI, 0.19020-0.23215). When analyzing participating ophthalmologists with available Medicare payment data (11 193), a total of 8777 (78.4%) achieved exceptional MIPS scores corresponding to mean (SD) adjustments per physician of $244.60 ($217.36) to $4864.78 ($4323.08), or 0.07% ($2 146 835.21 of $3 212 011 252.88) to 1.33% ($42 698 166.89 of $3 212 011 252.88), of the total nondrug Medicare payment.

Conclusions and Relevance

Results of this economic evaluation showed that although 78.4% of ophthalmologists received exceptional positive payment adjustments, roughly 84% (798916 of 954615) of all health care professionals nationally achieved this benchmark. Exceptional MIPS was associated with filing as group or APM, resulting in, on average, a relatively small additional payment per participant; this suggests that ophthalmologists who file as individuals should consider an alternative filing approach. Changes in MIPS methodology may disproportionately affect certain ophthalmologists, which warrants further study.

Introduction

The Medicare Sustainable Growth Rate (SGR) was part of the Balanced Budget Act of 1997 intended to limit health care expenditures by reducing physician reimbursement to match the growth in utilization of Medicare services. The Sustainable Growth Rate was repealed and replaced by the Quality Payment Program (QPP) of the Medicare Access and CHIP Reauthorization Act (MACRA) of 2015 to allow for value-adjusted payment changes for physicians accepting Medicare. The QPP was implemented on January 1, 2017, and requires physicians to receive increased or decreased payment based on relative quality metrics through 1 of 2 tracks: the Merit-Based Incentive Payment System (MIPS) or advanced alternative payment models (APMs).¹ In the traditional MIPS framework for individuals and groups, performance scores are weighted across 4 categories: quality, cost, improvement activities (IAs), and promoting interoperability. Final-weighted MIPS scores contribute to payment adjustments for Medicare Part B which are applied approximately 2 years after the MIPS performance year (PY).² APMs operate under special arrangements with US Centers for Medicare & Medicad Services (CMS) in which cost and utilization are evaluated separately. Therefore, APMs are subject to different MIPS score weighting.³

After MACRA, ophthalmologists were predicted to participate in QPP primarily through MIPS with continued fee-for-service. This raised concerns among ophthalmologists about comparatively lower reimbursement and disproportionate difficulty with specialty agnostic measures for ophthalmologists.⁴ Given the QPP’s attempt to consolidate quality and value programs across physicians, specialists were concerned about the specific effect on their respective fields. For example, QPP concerns were raised across multiple specialties, including among interventional pain medicine practitioners,⁵ neurointerventional specialists,⁶ gynecologic oncologists,⁷ and dermatologists.⁸ Radiation oncology practices reported the cost of compliance with MACRA significantly exceeded CMS estimates, with high levels of dissatisfaction with the ease of submitting data and measures.⁹ Efforts from the American Academy of Ophthalmology (AAO) and IRIS (Intelligent Research in Sight) Registry have facilitated reporting and allowed for dozens of ophthalmology-specific quality measures. MIPS scores for eye care professionals in 2017 were found to be statistically significantly greater for ophthalmologists compared with optometrists as well as all other physicians when stratified for urbanicity and group or individual reporting.¹⁰ Individual reporting was associated with lower MIPS performance (and lower odds of bonus payment) than group or APM reporting for otolaryngology,¹¹ radiology,¹² nephrology,¹³ anesthesiology,¹⁴ and orthopedics.¹⁵ To our knowledge, the economic consequences after initiation of MIPS payment adjustments and the influence of reporting category on ophthalmologists have been minimally reported. Systematic differences in performance based on filing entity could undermine the intention of MIPS to reward physicians for high-value care and could potentially disincentivize participation. Therefore, we sought to characterize the performance and economic changes associated with MIPS for ophthalmologists in PY 2019.

Methods

The Vanderbilt University Medical Center institutional review board exempted this study from review because the study did not meet the criteria for human research; therefore, informed consent was not required. No identifiable data were used in the study. Race and ethnicity data for ophthalmologists are not included in the CMS database and therefore were not analyzed. The study complied with the tenets of the Declaration of Helsinki. We followed the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) reporting guidelines where applicable.

MIPS scores by category were sourced from the CMS PY 2019 Overall MIPS Performance file.¹⁶ National Provider Identifier numbers for ophthalmologists participating in Medicare Part B were sourced from CMS.gov Medicare Physician & Other Practitioners by provider file, which was last updated to include 2019 data.¹⁷ This yielded 17 804 ophthalmologists from 1 115 870 total Medicare health care professionals. MIPS data were not available for 4183 ophthalmologists. This may have been attributable to reporting requirements for MIPS, such as falling below the low-volume threshold criteria (as determined by minimum total billing, patients with Part B coverage were evaluated, and minimum covered professional services in relevant 12-month segments of the MIPS determination period)¹⁸ or participating in other QPP programs with MIPS exemption. APMs are subject to specific arrangements in which physicians or groups assume financial risk related to their patients’ outcomes and costs. APMs meeting criteria to be determined a qualifying advanced APM participant based on payments or patients are exempt from MIPS and instead receive a 5% incentive payment. These physicians can report quality standards through alternative pathways or voluntarily report through MIPS. APMs that do not meet all the requirements of qualifying advanced APM participants must file through MIPs via the APM scoring standard.³

MIPS performance in 2019 was based on a complex algorithm with numerous potential measures. Briefly, 4 categories of performance are included for individuals or groups: quality (45% of total score, generally from 6 choices of quality measures that can include the Consumer Assessment of Healthcare Providers and Systems for MIPS Survey or another predefined measure set/registry), cost (15% of total score, from up to 10 cost measures sourced from Medicare claims data), IA (15% of total score, from 1-4 weighted IAs), and promoting interoperability scores (25% of total score, based on a single set of measures and objectives). Virtual groups, which are combinations of 2 or more practitioners who elect to submit data together, are also subject to this scoring methodology, though there are alternate facility-based scoring nuances for physicians participating as a group or APM. APM MIPS participants specifically were not scored based on the cost category for PY 2019 because this is accounted for in other prearranged cost and utilization metrics. Instead, APM scoring was weighted 50% quality performance, 0% cost performance, 30% IAs, and 20% promoting interoperability.³

The final MIPS score ranges from 0 to 100 points and determines the MIPS payment adjustment: 75.00 to 100.00 points, positive MIPS adjustment plus potential additional adjustment for exceptional performance (based on potential funds available); 30.01 to 74.99 points, positive MIPS adjustment (based on potential funds available); 30.00 points, neutral payment adjustment; 7.51 to 29.99 negative MIPS payment adjustment (defined as between −7% and 0%); 0 to 7.50 points, negative MIPS payment adjustment (defined as a maximum of −7%).² MIPS payment adjustments are applied 2 years after the performance year; therefore, PY 2019 corresponds to payment adjustments in 2021.

Estimation of Payment Adjustments

MIPS payment adjustments were estimated based on the minimum and maximum adjustment rates on QPP participation results reported from 2019 PY: negative (−0.01% to −7.00%), neutral (0%), positive (0%-0%), and exceptional (0.09%-1.79%).¹⁹ Given the high percentage of physicians qualifying for positive adjustments, it is likely that the reported QPP positive adjustment rates of 0% to 0% lacked sufficient significant figures to capture small but nonzero adjustments. To estimate this range of payments, a positive adjustment was estimated to be between 0.000% to 0.005%. These ranges were used to estimate payment adjustments based on total Medicare payment data from the Medicare Physician & Other Practitioners by Provider.¹⁷ Specifically, the Total Medical Medicare Payment Amount was used because this excludes deductibles, coinsurance, and Medicare Part B drug services not eligible for MIPS payment adjustments.²⁰ To assess the magnitude of payment adjustments for individual ophthalmologists, the Total Medical Medicare Allowed Amount was used because this includes potential revenue from deductible and coinsurance, but this excludes drug related payments. A total of 2428 ophthalmologists who did not have data for medical Medicare payments were excluded from the average payment adjustment analysis.

Statistical Analysis

Based on these scoring rules, summary statistics and payment adjustment calculations were performed in Microsoft Excel. Subanalyses were performed based on filing category (APM, individual, and group based on the 2019 MIPS clinical performance data set). Single-factor analysis of variance (ANOVA) tests were used to compare scores across filing categories given the large sample size for each category. Virtual group was excluded in these tests, and participants without a MIPS eligibility category were excluded from these subanalyses. Kruskal-Wallis tests were performed given the nonnormal distribution of scores; however, test statistics were artificially high owing to the large sample size in each category. As a result, parametric ANOVA testing using the 1-tailed F distribution was determined to be sufficiently rigorous. In addition, odds ratio (OR) calculation required a Haldane-Anscombe correction (addition of 0.5 for zero-unit categories).²¹ P values were not adjusted for multiple analyses. Significance was defined as P < .05. Planned analyses for performance based on urbanicity could not be performed owing to the low sample size of nonurban participants.

Results

Of 17 804 ophthalmologists registered for Medicare Part B, 13 621 (10 445 [76.68%] men; 3176 women [23.32%]) participated in the QPP through traditional MIPS for the 2019 PY. Ophthalmologists practiced in a predominantly large metropolitan area (12 302 [90.32%]) of 50 000 residents. Participants submitted data through MIPS eligibility filing categories of APM (2102 [15.43%]), group (8369 [61.44%]), individual (3144 [23.08%]), and virtual group (6 [0.04%]) (Table 1).

Table 1. Merit-Based Incentive Payment System (MIPS) Individual Participant Demographics by Medicare Categorization.

Participant (scored)	No. (% total participants)
Total No.	13 621
Medicare self-reported gender
Male	10 445 (76.68)
Female	3176 (23.32)
Medicare reported urbanicity
Metropolitan area
Core: primary flow within an urbanized area of 50 000 and greater	12 302 (90.32)
High commuting: primary flow 30% or more to an urbanized area of 50 000 and greater	128 (0.94)
Low commuting: primary flow 10% to <30% to an urbanized area of 50 000 and greater	3 (0.02)
Micropolitan
Area core: primary flow within an urban cluster of 10 000-49 999	790 (5.80)
High commuting: primary flow 30% or more to an urban cluster of 10 000-49 999	26 (0.19)
Rural areas: primary flow to a tract outside an urbanized area of 50 000 and greater or urban cluster	23 (0.17)
Secondary flow
30% to <50% to a larger urbanized area of 50 000 and greater	164 (1.20)
30% to <50% to an urban cluster of 10 000-49 999	6 (0.04)
30% to <50% to an urbanized area of 50 000 and greater	36 (0.26)
Small town
Core: primary flow within an urban cluster of 2500-9999	116 (0.85)
High commuting: primary flow 30% or more to an urban cluster of 2500-9999	7 (0.05)
Unknown	20 (0.15)
MIPS filing category
Alternative payment method	2102 (15.43)
Group	8369 (61.44)
Individual	3144 (23.08)
Virtual group	6 (0.04)

Mean (SD) participant MIPS score was 83.45 (20.27) points. Although most participants were scored in the quality (12 575 of 13 621 [92.3%]) and IA (12 415 of 13 621 [91.1%]) categories, only 8630 of 13 621 (63.4%) and 7735 of 13 621 (56.8%) received scores for the process improvement and cost categories, respectively, and therefore were subject to score reweighting rules.² Total mean (SD) score (83.45 [20.27]; P < .001), quality score (90.87 [16.74]; P < .001), process improvement score (77.42 [16.61]; P < .001), and IA score (39.91 [1.32]; P = .001) were different across MIPS eligible filing categories. No participants in the APM and individual category were found to have a cost score (Table 2).

Table 2. Average Merit-Based Incentive Payment System (MIPS) Scores by Category for Participants in 2019 MIPS Performance Period.

Score category	Filing category	No. with score >0	% Total scored participants	Mean (SD) score	ANOVA P value
Total score		13 621	100	83.45 (20.27)
	APM	2102	15.43	95.39 (3.17)	<.001
	Group	8369	61.44	86.04 (15.12)
	Individual	3144	23.08	68.72 (28.74)
	Virtual group	6	0.04	18.53 (28.71)
Quality score		12 575	92.3	90.87 (16.74)
	APM	2096	15.39	99.56 (2.09)	<.001
	Group	8223	60.37	91.27 (15.36)
	Individual	2254	16.55	81.36 (23.17)
	Virtual group	2	0.01	80.40 (0)
PI score		8630	63.4	77.42 (16.61)
	APM	2081	15.28	75.06 (9.54)	<.001
	Group	5475	40.20	77.82 (17.60)
	Individual	1074	7.88	79.99 (21.02)
	Virtual group	0	0.00	NA
IA score		12 415	91.1	39.91 (1.32)
	APM	2102	15.43	40 (0)	.001
	Group	8046	59.07	39.90 (1.38)
	Individual	2265	16.63	39.87 (1.54)
	Virtual group	2	0.01	20 (0)
Cost score		7735	56.8	74.14 (11.92)
	APM	0	0.00	NA	NA
	group	7733	56.77	74.14 (11.92)
	Individual	0	0.00	NA
	Virtual group	2	0.01	79.5 (0)

Abbreviations: ANOVA, analysis of variance; APM, alternative payment method; IA, improvement activity; NA, not applicable; PI, process improvement.

For PY 2019, 76.5% of ophthalmology participants (13 621) who registered for Medicare participated in the MIPS pathway of the QPP. Roughly 99% of participants (11 182) received nonnegative reimbursement adjustments. A total of 11 193 ophthalmologists participating in the 2019 MIPS program had available Medicare payment data. The vast majority (10 367 [92.6%]) of participants with available data were eligible for a positive payment adjustment, with 815 (7.28%) receiving MIPS total scores corresponding to neutral payment adjustments and 11 (0.10%) corresponding to negative payment adjustments. The estimated total payment adjustment for ophthalmologists for PY 2019 was $2 146 835.21 to $42 698 166.89 for those with exceptional performance, $0 to $19 960.18 for those with positive performance, −$940.50 to −$28 346.97 for those with negative performance, and −$83 543.80 to −$83 543.80 for those with maximum negative performance. The estimated mean (SD) payment adjustment per participant ranged from $244.60 ($217.36) to −$20 885.95 ($14 748.01). A total of 8777 participating ophthalmologists (78.4%) achieved exceptional MIPS scores corresponding to mean (SD) adjustments of $244.60 ($217.36) to $4864.78 ($4323.08) per participant, which represents 0.07% ($2 146 835.21 of $3 212 011 252.88) to 1.33% ($42 698 166.89 of $3 212 011 252.88) of the mean medical Medicare payment per participant. Approximately 0.10% (11 of 11 193) of ophthalmologists achieved scores corresponding to negative payment adjustments (Table 3).

Table 3. Estimated Payment Adjustments for 2019 Merit-Based Incentive Payment System (MIPS) Performance Period in US Dollars.

MIPS payment adjustment	Ophthalmologists, No. (%) (n = 11 193)a	Estimated mean minimum adjustment	Estimated maximum adjustment	Estimated total minimum adjustment	Estimated total maximum adjustment
Positive
Exceptional (75.00-100.00)	8777 (78.42)	244.60	4864.78	2 146 835.21	42 698 166.89
Positive (30.01-74.99)	1590 (14.21)	NA	12.55	NA	19 960.18
Neutral
Neutral (30.00)	815 (7.28)	NA	NA	NA	NA
Negative
Negativeb (7.51-29.99)	7 (0.06)	−5.79	−4049.57	−940.50	−28 346.97
Maximum negativeb (0-7.50)	4 (0.04)	−20 885.95	−20 885.95	−83 543.80	−83 543.80

Abbreviation: NA, not applicable.

^a Total number of participating ophthalmologists with available Medicare payment data for 2019.

^b For the 2019 performance year, most negative payment adjustments were attributable to physicians who were eligible yet did not submit data, and these adjustments were reassigned to a neutral adjustment instead of the maximum negative penalty based on the Automatic Extreme and Uncontrollable Circumstances policy.¹⁹

In terms of performance and payment by filing category, exceptional performance and the corresponding high-payment adjustment was achieved by 100% (1753 of 1753) of APM MIPS participants, 83% (5679 of 6812) of group MIPS participants, and 51% (1345 of 2622) of individual MIPS participants. Ophthalmologists filing as individuals were less likely to achieve exceptional performance (MIPS score from 75.00-100.00) than APM participants (OR, 0.0003; 95% CI, 0.00002-0.00481) and group participants (OR, 0.21013; 95% CI, 0.19020-0.23215) (Table 4).

Table 4. Estimated Payment Adjustments for 2019 Merit-Based Incentive Payment System Performance Period in US Dollars (USD) by Filing Category.

File category	No. (%)						Minimum mean (SD) payment, $	Maximum mean (SD) payment, $
	Total	Exceptional (75.00-100.00)	Positive (30.01-74.99)	Neutral (30.00)	Negativea (7.51-29.99)	Maximum negativea (0-7.50)
APM	1753	1753 (100)	0 (0)	0 (0)	0 (0)	0 (0)	188.94 (176.67)	3757.78 (3513.78)
Group	6812	5679 (83)	1064 (16)	62 (1)	7 (0)	0 (0)	209.02 (226.11)	4155.10 (4501.53)
Individual	2622	1345 (51)	524 (20)	753 (29)	0 (0)	0 (0)	149.39 (212.28)	2973.99 (4220.01)
Virtual group	6	0 (0)	2 (33)	0 (0)	0 (0)	4 (66)	−13 923.9 (15 710.77)	−13 919.45 (15 715.58)

Abbreviation: APM, alternative payment method.

^a For the 2019 performance year, most negative payment adjustments were attributable to physicians who were eligible yet did not submit data, and these adjustments were reassigned to a neutral adjustment instead of the maximum negative penalty based on the Automatic Extreme and Uncontrollable Circumstances policy.¹⁹

Discussion

In the current economic evaluation, most participating ophthalmologists (92.6%) were eligible for positive MIPS payment adjustments, with 78.4% achieving exceptional MIPS scores corresponding to total payment adjustments of $2 146 835.21 to $42 698 166.89 nationally. However, this corresponds to individual mean adjustments of $244.60 to $4864.78 per participant, or 0.07% to 1.33% of the mean medical Medicare payment per participant, which does not include Medicare drug revenue or non-Medicare revenue. Only 0.10% of ophthalmologists achieved MIPS scores corresponding to negative payment adjustments, with 0.04% of ophthalmologists with sufficiently low scores to receive the maximum negative adjustment (in PY 2019 corresponding to −$20 885.95 individually). However, most negative payment adjustments for PY 2019 were attributable to physicians who were eligible yet did not submit data. These adjustments were reassigned to a neutral adjustment instead of the maximum negative penalty based on the Automatic Extreme and Uncontrollable Circumstances policy.¹⁹ Therefore, it is unclear whether these participants in fact received the negative penalties. Although the MIPS payment adjustments for the PY 2019 appear relatively minor and primarily positive, the potential effect in future performance years warrants discussion of the methodology and nuances of MIPS scoring for ophthalmology professionals.

Positive payment adjustments are limited by a budget neutrality adjustment and subsequent scaling factor.¹⁹ Although exceptional payment adjustments are not subject to budget neutrality, the total payment adjustments to all eligible physicians must proportionately distribute the $500 million of available funds. Given this limitation, the upper national payment adjustment range of $42 698 166.89 is unlikely; however, to our knowledge there are no reported data regarding the specific adjustments furnished to improve the accuracy of this estimate. This further explains the relatively low individual economic effect of adjustments to physicians. This calls into question whether the economic incentive for achieving these scores justifies the added practice burden. To our knowledge, there is no reported evidence correlating MIPS scores with superior patient outcomes.

As performance thresholds become increasingly rigorous, the individual economic effect is expected to become magnified. Although 78.4% of ophthalmologists received exceptional positive payment adjustments, roughly 84% of all health care professionals nationally achieved this benchmark. The comparatively lower performance of ophthalmologists may be attributable to a variety of factors, including differences in performance metrics or the specific breakdown of reporting category (ie, the relative percentage of ophthalmologists participating through MIPS APM scoring) relative to other specialties.

There were differences in the mean scores by MIPS eligibility categories. Individual participants showed lower mean scores, and they were less likely than APM or group participants to achieve the highest level of payment adjustment. Those filing individually may have had lower quality scores owing to artifactual difference from lower case numbers or simply selection of different quality metrics. Additionally, group or APM participants may have benefited from efficiencies in electronic health record utilization and data collection, which may explain their relatively higher MIPS scores. Ophthalmologists who are in large academic groups or multispecialty medical groups work under a group-reporting option. These ophthalmologists rely on the performance of the entire physician group for more general medical performance measures along with reporting from the electronic health record.

Our findings here corroborate prior findings in otolaryngology and radiology, where those filing as individuals were found to have lower scores and increased likelihood of facing negative payment adjustments compared with groups or APMs.¹² Xiao et al¹¹ similarly found higher MIPS scores for those reporting via APMs, driven largely by higher quality category scores and lower variance in other subcategory scores. After its inception, MACRA’s QPP was expected to result in lower reimbursement for ophthalmologists and disproportionately burden individual ophthalmologists in smaller, rural practices.⁴ These concerns appear valid given the current disproportionate scores for PY 2019. Although proximity to a metropolitan core and subsequent commuting vary, at least 1299 participants here are not classified as within a metropolitan area core (Table 1). Although there were relatively few participants that could be classified as completely rural,²² in 2017, 97% of rural counties did not have a single ophthalmologist.²³ Market saturation may not lead to increased utilization,²⁴ and further study of disparities in eye-care quality or value across the rural-urban continuum may inform be helpful for policy and advocacy efforts.

The limited MIPS metrics applicable to ophthalmology may introduce bias in MIPS scores across eligibility types as well as subsequent payment adjustments. This may become important as the weighting of the cost metric will increase to 20% of the total MIPS score for PY 2021, and the cost performance category weight is required to be 30% beginning with PY 2022. Routine cataract removal with intraocular lens implantation appears to be the only ophthalmologic cost measure included for PY 2019. This measure is defined as an episode-based cost measure, which is calculated as the mean cost to Medicare for beneficiaries undergoing cataract surgery during a global period relative to the expected costs predicted by a risk adjustment model, which is scaled by the national average observed episode cost.²⁵ This may disproportionately affect cataract surgeons relative to other subspecialists. Although the current data set does not include detail for subspecialty performance, further study of performance by subspecialty can help ensure appropriate quality and cost metrics are established.

Of note, the observed to expected episode cost methodology reflects expenditure from the perspective of CMS, but this approach will not evaluate the true cost of a care episode for a practice. True cost calculation likely requires a bottom-up costing approach,²⁶ which would involve granular accounting for all cost inputs for each care episode rather than merely dividing a lump sum of costs over each episode. MIPS may promote value from the perspective of CMS, but this may not be an accurate representation of true value (eg, outcomes relative to total costs).

In a similar vein, there are varied ophthalmologic quality metrics that did not have a historical benchmark for PY 2019.²⁷ The IRIS Registry is a free resource to AAO members that facilitates MIPS participation and clinical data research and provides tools for practice management.²⁸ The AAO has worked to increase the number of eye-specific measures. In 2019, there were 15 ophthalmology specific measures of which ophthalmologists needed to submit 6 measures. As quality measures evolve, IRIS continues to derive new eye-related measures²⁹ allowing ophthalmologists of varying subspecialties and practice patterns to report appropriate quality data. It should be noted that to provide the IRIS registry as a no cost member benefit, the AAO licensed commercialization of the IRIS Registry data to Verana Health as a revenue stream to cover operating costs.

Limitations

This study has certain limitations. Importantly, the percentage of Medicare health care professionals who participated in the MIPS QPP pathway is not an estimate of the overall participation of ophthalmologists in MIPS. Many registered health care professionals may be ineligible, or participate through an advanced APM, therefore the participation rate should not be inferred from the data methodology here. Likewise, based on thresholds for reporting, the number of physicians who report measures that meet the public reporting standards is less than the total number of physicians who received an overall MIPS score. In fact, most MIPS-eligible physicians participated in QPP in PY 2019 with 97.44% of engaged physicians receiving a MIPS score and payment adjustment.¹⁹ The estimated MIPS payment adjustments are likely different from the exact payment adjustment received by the physicians themselves. Payment adjustment ranges were sourced from the entire pool of MIPS-eligible physicians, and it is possible that the ophthalmologist distribution was more heavily concentrated in a specific category of scaled MIPS payment. In addition, MIPS adjustments are applied before Medicare fee-for-service payments are reduced by any necessary sequestration as outlined in the Budget Control Act of 2011²⁰; therefore, the analysis here may overestimate the degree of payment adjustments subject to further sequestration.

Conclusions

The results of this economic evaluation revealed that most participating ophthalmologists received positive albeit relatively small payment adjustments for MIPS PY 2019; however, participants reporting as individuals received lower MIPS scores and were less likely to receive the maximum payment adjustment. The association of filing as group or APM with exceptional MIPS suggests that ophthalmologists who file as individuals should consider an alternative filing approach. Changes in MIPS methodology may disproportionately affect certain ophthalmologists, which warrants further study. As performance thresholds and quality metrics are more stringently defined in subsequent performance years after the COVID-19 pandemic, MIPS may contribute to larger variation in Medicare reimbursement across health care professionals and practice types. Therefore, the specific reporting standards, quality measures, and comparative benchmarks should be determined by ophthalmologists with consideration for downstream practice pattern changes and ultimately yielding true quality differences.