Pandemic Pause: Systematic Review of Cost Variables for Ambulatory Care Organizations Participating in Accountable Care Organizations

Ambulatory health care provider organizations participating in Accountable Care Organizations (ACOs) organizations assume costs beyond typical practice operations that are directly associated with value-based care initiatives. Identifying these variables that influence such costs are essential to an organization’s financial viability. To enable the U.S. healthcare system to respond to the COVID-19 pandemic CMS issued blanket waivers that permit enhanced flexibility, extension, and other emergency declaration changes to ACO reporting requirements through the unforeseen future. This relaxation and even pausing of reporting requirements encouraged the researchers to conduct a systematic review and identify variables that have influenced costs incurred by ambulatory care organizations participating in ACOs prior to the emergency declaration. The research findings identified ACO-ambulatory care variables (enhanced patient care management, health information technology improvements, and organizational ownership/reimbursement models) that helped to reduce costs to the ambulatory care organization. Additional variables (social determinants of health/environmental conditions, lack of integration/standardization, and misalignment of financial incentives) were also identified in the literature as having influenced costs for ambulatory care organizations while participating in an ACO initiative with CMS. Findings can assist ambulatory care organizations to focus on new and optimized strategies as they begin to prepare for the post-pandemic resumption of ACO quality reporting requirements once the emergency declaration is eventually lifted.


Rational
The novel Coronavirus (COVID- 19) global pandemic has impacted the United States healthcare industry dramatically. Since March 2020, treatment protocols and access to care have been affected, challenging the quality of care provided to patients of all acuity levels [1][2][3]. This deferment of care exacerbated chronic illnesses and related symptoms, and a reduction of routine and preventative care continues to hide as a secondary concern behind the ongoing COVID-19 virus surges and initiatives to increase physical distancing and other public health measures [4,5]. To assist health care organizations in treating patients requiring immediate, acute care related to the pandemic, the Centers for Medicare and Medicaid Services (CMS) has relaxed the Quality Payment Program (QPP) reporting requirements for Accountable Care Organizations (ACOs) [6]. Further, recent provider practice pattern shifts from the pre-COVID- 19 values-based quality metric reporting system for ACO-involved organizations offers an assessment opportunity to identify key costinfluencing variables within the ACO environment.

Objectives
Since the Patient Protection and Affordable Care Act (2010) and the updated valuebased payment reform initiatives of the Medicare Access and CHIP Reauthorization Act (2015), many ambulatory care organizations have participated in ACOs. These organizations have assumed risk-based reimbursement challenges with varying results. The ambulatory care management team, confronted with reducing the cost of care while maintaining and improving patient quality of care and treatment outcomes, experience additional operational costs to their organization when participating in ACOs. The current QPP reporting accommodations for these organizations allows for a reflection on costs associated with ambulatory care (outpatient) organizations participating in ACOs for the period between 2015 and early 2020 significantly affected by MACRA (2015). The identification of variables during the evaluation period that both increase and reduce costs associated with ambulatory care organizations while currently participating in ACO reimbursement models since the last QPP updates can assist outpatient organizations in their resumption of routine operations and best-practice process design once the pandemic's effect on the industry has subsided.

Methods
This systematic review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Literature for this review related to accountable care organizations and ambulatory care provider organizations was obtained from four separate databases: (CINAHL) Complete, Academic Search Ultimate, Business Source Ultimate via the Ebson B. Stephens Company (EBSCO host) and PubMed (which queries MEDLINE). Overall, four databases were utilized to broaden the search due to an initial observation of limited publications meeting the search criteria. Peer-reviewed publications specific to ambulatory care organizational costs directly related to an ACO model's reimbursement is limited and therefore important to be identified as post-pandemic preparations for the return to routine operations begin.
The researchers focused on ambulatory care/outpatient organizations and an investigation into costs associated with accountable care organization participation. Medical Subject Headings (MeSH) is the National Library of Medicine controlled vocabulary thesaurus utilized to index research articles for PubMed (MEDLINE) and was used to identify key words in the search. Boolean search operators were used to ensure proper word/phrases to capture all applicable literature for the sample as indicated by MeSH terms and follow-on "exploding" terminology specific to ambulatory care organizations. The variable of "cost" was truncated in the search string to assist in potential variations of the term ( Figure 1).
Healthcare 2021, 9, x follow-on "exploding" terminology specific to ambulatory care organiza The variable of "cost" was truncated in the search string to assist in pot variations of the term ( Figure 1).

Inclusion Process
To be included in the sample, publications must have occurred bet 1 January 2015 and 1 October 2020. This specific publication date range cr were utilized to ensure studies identified were appliable to the most-r Medicare Access and CHIP Reauthorization Act (2015) value-based repo criteria as implemented by the CMS Alternate Payment Method (A Quality Payment Program (QPP) for ACOs [7]. Editorials, govern reports, letters to the editor, or other studies not based upon emp evidence were not considered in this review. Full text was not included initial search criteria in an attempt to simply locate the applicable liter

Inclusion Process
To be included in the sample, publications must have occurred between 1 January 2015 and 1 October 2020. This specific publication date range criteria were utilized to ensure studies identified were appliable to the most-recent Medicare Access and CHIP Reauthorization Act (2015) value-based reporting criteria as implemented by the CMS Alternate Payment Method (APM) Quality Payment Program (QPP) for ACOs [7]. Editorials, government reports, letters to the editor, or other studies not based upon empirical evidence were not considered in this review. Full text was not included in the initial search criteria in an attempt to simply locate the applicable literature (citations) and permit the researchers to conduct follow-up on individual article searches for full text of identified citations via their three separate research institutions' online library databases (therefore increasing review validity and also sample size). The researchers were able to locate 100% of the final sample in full-text format for follow-on extensive review. Studies in this review had to involve ambulatory care (outpatient) organizations and measurable costs as associated with their participation in a Medicare ACO alternative payment model. Specific facilitators and barriers to cost inflation and/or reduction were intended themes to be identified, as previous reviews of literature in this specific industry segment and related costs associated with accountable care organizations remains limited. Many publications included in the review also address costs incurred by network hospitals and other integrated systems in addition to ambulatory care service locations. While the ACO program and its related value-based and shared-savings criteria have been adjusted over time, this review focused specifically on cost evidence as applied to ambulatory care organizations in order to review their investments in value-based care, as compared to solely hospitals and other large hospital networks/ancillary systems.
This study's information came from secondary data sources (library research database). All of the literature included in this research is publicly available and any individual research subjects (if present) are unidentifiable. As a result, this systematic review qualifies under "exempt" status in 45 Code of Federal Regulations (CFR) 46. An institutional review board review was not required, and no consent was necessary. Figure 2 demonstrates the article exclusion process, beginning with the initial research database searches and ending with the final literature sample (n = 25). Initially, 525 articles met the primary search criteria, addressing the variables of both ambulatory care, accountable care organizations, and cost. While four research databases were utilized in this study to help increase the literature sample size, a consequence of this decision was a high frequency of duplicate articles identified (35 total duplicates). Upon filtering these results for the study's specified date range to further identify costs as applicable to the MACRA (2015) policy implementation period (pre-pandemic), and also English-only, academic/peer-reviewed journals, 455 articles were excluded from the study, leaving 35 remaining in the study sample. These remaining 35 articles were then downloaded by the research team (full text) and thoroughly reviewed. All researchers reviewed the literature to ensure each was germane to the study's initiative.

Exclusion Process
Upon completion of the final screening process, the research team decided to remove an additional 10 articles from the sample for the following reasons: letters to the editor (−2 articles), cost variables not identifiable and/or attributable to ACOs (−3), and not directly applicable/focused on ambulatory care organizations (−5). These measures were conducted by team meetings (via webinar) by the research team on multiple occasions and all researchers reached a consensus (100% agreement) on article exclusions and the solidification of the final literature sample (n = 25).
The researchers have significant experience managing in the ambulatory care environment and the decision was made to review all the literature sample independently. Further, individually identified underlying themes (constructs) as related to cost influencers and costs preventions as experienced by ambulatory care organizations participating in ACOs were identified. To further categorize and synthesize results and to increase inclusion of findings, researchers further classified identified themes into final study variables related to costs associated with ambulatory care organizations participating in ACOs (secondary/final theme) in complete agreement. Finally, quality assessment of the literature in the sample was conducted using the Johns Hopkins Nursing Evidence-Based Practice Model (JHNEBP) to further identify types of studies identified.
for the study's specified date range to further identify costs as applicable to the MACRA (2015) policy implementation period (pre-pandemic), and also English-only, academic/peer-reviewed journals, 455 articles were excluded from the study, leaving 35 remaining in the study sample. These remaining 35 articles were then downloaded by the research team (full text) and thoroughly reviewed. All researchers reviewed the literature to ensure each was germane to the study's initiative. Upon completion of the final screening process, the research team decided to remove an additional 10 articles from the sample for the following reasons: letters to the editor (-2 articles), cost variables not identifiable and/or attributable to ACOs (−3), and not directly applicable/focused on ambulatory care organizations (-5). These measures were conducted by team meetings (via webinar) by the research team on multiple occasions and all researchers

Results
According to the JHNEBP classification model, 76% (19) of the identified articles were categorized as Level 2, or quasi-experimental studies. These studies often used a pre-and post-assessment or group difference analysis of an ACO's patient outcomes and related organizational cost information. Other identified articles fell within Level 3 studies classified as non-experimental in nature, yet still met the criteria for this study and assessment of costs incurred or prevented by ambulatory care organizations participating in ACOs. JHNEBP Levels 4 and 5 (studies related to expert opinion and/or panel recommendations) were not included in the study (Table 1). Integration with community health centers and/or hospitals. ACO performance on diabetes management decreased after contract year one (possibly due to transition from pay-for-reporting to pay-for-performance). Lin et al. [19] Medicare ACO claims data to analyze in and out of network specialty care. Under-resourced and highly regulated Medicaid models at the state level. Over-reliance upon claims data only, versus the incorporation of clinical-outcomes data. Additionally, Table 1 also addresses facilitators related to cost prevention strategies for ambulatory care organizations participating in ACOs. Cost reduction findings and/or experiences by participating outpatient care organizations are summarized, while cost reduction barriers, either an inability to decrease cost or possibly even contribution towards increasing costs are notated. While it may be assumed that an inability of an outpatient care organization to correctly implement the study's identified cost reduction facilitators would lead to increase cost, additional identified barriers to cost prevention/reduction (leading to increases in costs) are also presented in Table 1.
Once all articles were reviewed and underlying themes (constructs) identified and finalized, researchers met to review individual results and collectively decide upon a single affinity matrix. Agreement was reached on cost influencing and cost prevention variables and article assignments, or coding. Each had to agree on each identified article's inclusion into each thematic category. Article inclusion into thematic categories was not mutually exclusive, and often a single article met criteria for multiple cost influencer and/or reducer categories (Figures 3 and 4).
prevention/reduction (leading to increases in costs) are also presented in Table 1.
Once all articles were reviewed and underlying themes (constructs) identified and finalized, researchers met to review individual results and collectively decide upon a single affinity matrix. Agreement was reached on cost influencing and cost prevention variables and article assignments, or coding. Each had to agree on each identified article' inclusion into each thematic category. Article inclusion into thematic categories was no mutually exclusive, and often a single article met criteria for multiple cost influence and/or reducer categories (Figures 3 and 4).

Discussion
The systematic review identified key the variables that influence cost. Understandin and addressing these variables can play an important role for the ACO to contribute t organizational financial viability. These variables identify interventions that can help reduce costs when implemented as well as inform ACOs on key areas that need to b addressed and if left unmanaged can lead to increased costs to the ACO.

Discussion
The systematic review identified key the variables that influence cost. Understanding and addressing these variables can play an important role for the ACO to contribute to organizational financial viability. These variables identify interventions that can help reduce costs when implemented as well as inform ACOs on key areas that need to be addressed and if left unmanaged can lead to increased costs to the ACO.

Cost Reduction: Enhanced Care Management/Patient Navigation
Most consistent with CMS initiatives and the ACO model patient-centered care focus, the incorporation of a patient care management program and patient navigation processes were identified as most prevalent in the literature to assist with cost reduction. This finding suggests that those outpatient organizations investing in patient-level quality of care/care coordination activities experience cost reduction along with improved clinical outcomes.
Care intensive, patient acuity-based programs were implemented by many of the outpatient organizations to support this initiative [11,13,24]. Such programs developed by these organizations specifically worked to identify indicators of potential current and/or future illness and cost drivers as related to specific diagnoses associated with high risk and therefore high-cost treatment options. Most noticeable and cost effective was an outpatient program's ability to custom tailor these initiatives to the specific communities they served and inherent characteristics specific to the various environment of care [24].
Investment in gathering community demographics and other characteristics is also cited as a best practice [14]. Such investment in market analysis, the health status of the population served, and making investments in addressing disparity leading gaps to improve health not only demonstrates an investment in population health but will also benefit the organization's quality reporting efforts.
Patient education and the implementation and expansion upon patient self-care responsibilities contributed to significant cost reductions for outpatient organizations involved with the ACO model. Specifically, a program developed to identify those patients with the ability to provide their own self-care at home was initiated to support overall value-based care [12]. This initiative was also commonly identified in the literature as a contributing variable for outpatient ACO cost reductions with advanced telehealth treatment expansion initiatives [17,28].
The use of patient care navigators further contributed to identified cost reductions in the outpatient clinic literature. Such positions have been developed to assist patients (often virtually) during the global pandemic and beyond for both clinical and non-clinical initiatives [15,25]. Similar clinic-associated tasks conducted by employees and/or providers were identified as participating in such actions but not specifically identified as patient navigators [16]. Demonstrated cost reductions also involve the prevention of frequently experienced evaluation & management (E & M) visits for nursing home organizations [32].

Cost Reduction: Health Information Technology
The shift of clinical practice away from traditional silos of care to greater team focused care to achieve improved patient quality and cost benefits continues to be a healthcare delivery focus. User friendly Health Information Technology (HIT) is a critical enabler of this shift. HIT use across the clinical management continuum provides improved patient identification, clinical intervention tracking, outcomes monitoring tools, and the development of robust data sets to contribute to quality and process improvement efforts and ongoing identification of clinical best practices.
Aledade, a national network of independent practices has utilized a HIT platform to maximize the implementation and effectiveness of Medicare's Annual Wellness Visits (AWV). This ACO has implemented user friendly HIT enablement to ensure consistent identification of high-risk beneficiaries, facilitation of visit scheduling, optimizing visit workflow, and to provide data tools for performance monitor and best practice identification [29]. Other ACOs are seeing the promise of technology use and data integration and sharing by showing improved outcomes in high-risk Medicaid populations by utilizing clinical, claims, health plan enrollment and demographic data, as well as social service data provided by community health workers. Improved outcomes for this ACO include reduction in Emergency Department (ED) visits and an increase in utilization of primary care [30].

Cost Reduction: Ownership/Reimbursement Model
A cost reduction initiative identified in the literature surrounded the type of ambulatory care organization (specifically to ownership), as well as potential affiliation and/or other external organizations that may participate in the respective ACO network. Several studies support the identification of physician-owned organizations as the most successful models in limiting costs associated with ACO participation [18,22]. Such observation also possesses an inherent alignment of financial incentives for associated ACO stakeholders.
Physician-led ACOs have been the most successful type of risk bearing entity in the health value landscape as demonstrated by public reporting of the Medicare Shared Savings Program (MSSP). MSSP performance year results have consistently shown that smaller, physician-led ACOs are more likely to earn shared savings than hospital-led or integrated hospital and physician group-led ACOs [33]. Physician-led ACOs have done better at achieving savings despite less access to capital, less experience managing risk, and less sophisticated HIT systems [33]. Keeping with past trends, ACOs led by physician groups saw higher levels of savings in the MSSP than those led by hospital systems, saving an average of $114 per beneficiary compared to just $61 for hospital led ACOs in Performance Year 2019 [34]. Physician-led ACO success is also seen in the Medicaid program which lends verifiability across different population types in promoting value-based care [17,20,26,30].

Cost Influencer: Social Determinants of Health/Environmental
It is commonly accepted that health and illness follow a social gradient and when that gradient is tilted towards a lower socioeconomic status there is a greater negative impact on health and higher cost. The complex issues that need mending in our social fabric will not be easily solved. ACOs actively experience the negative cost impact of social determinants on member health and need interventions to address until larger, more systemic issues are resolved.
In addition to medically complex conditions, mental health and substance abuse issues, and psychosocial issues make a significant contribution to patient cost and complexity. Social determinants such as food insecurity, homelessness, social disruption, or lack of social support play a key role in health and illness. These characteristics contribute to patients being identified as both high-risk and high need [24]. Given the high rate of emergency department and inpatient care among homeless populations, this consideration should be given priority by the ACO team with living arrangement/home situation status being both assessed and addressed [8]. Given the cost impacts of socioeconomic variables improving the documentation of socioeconomic indicators through an ACOs HIT platform to measure and monitor health disparities can facilitate proactive intervention and care coordination. [30].

Cost Influencer: Integration/Standardization Challenges
A lack of standardization of health care services provided by clinicians significantly contributed to increased costs experienced by ACO outpatient organizations [14,29]. Those organizations that focused on clinical pathways that were supported by industry best practices and other identified clinic protocols often utilized the electronic medical record and clinical decision support systems (CDSS) to help standardize practice patterns. Further, the lack of evaluating and incorporating industry system challenges (referral processes, follow-up post-acute care, and other between-provider organization collaboration) was cited as a significant cost influencer for the outpatient clinic [12].

Cost Influencer: Misalignment of Financial Incentives
A major hurdle for physician-led ACOs to effectively execute on a value-based operational agenda that will effectively lower overall costs for a managed population is the misalignment of financial incentives. This is especially true when participant practices are still operating in a predominantly fee-for-service business model that directly competes with the value-based care focus of the ACO. This misalignment of financial incentives between value and volume is difficult to reconcile without a clear understanding of any specific medical practice's portfolio regarding payer mix with regard to risk-based reimbursement methods, or if/when the MSSP ACO contract transitions from pay-for-reporting to pay-for-performance measures-thereby necessitating investment in clinical transformation activities [10]. Given that the ACO program in Medicare appears to embed the assumption that large multispecialty organizations centered on hospitals will be best positioned to implement improved care delivery systems to lower costs [18], there could also be a misalignment in financial incentives due to practice ownership type. Research analysis of MSSP ACOs refutes the assumption that hospital-integrated practices are predisposed to advantage; however, as hospital-integrated ACOs did not produce savings in proportion to physician groups [22].

Study Limitations
As with any study, limitations exist. There is a lack of peer-reviewed research surrounding ambulatory care/outpatient organizations and their participation in ACOs. This led to a small sample size (n = 25). While many of the articles in the review (76%) were categorized by the researchers as Level 2, or quasi-experimental studies, each individual ambulatory care organization identified possessed its own inherent, unique challenges. As a result, the researchers were required to use broader-level thematic identification categories to best summarize the findings in the literature. Finally, a multitude of ACO models were included in this study (including two Medicaid ACOs). Future research on advanced ACOs, exclusive to model and risk-type is suggested.

Conclusions
The COVID-19 global pandemic has challenged the U.S. healthcare system and continues to stress provider organizations of all types. Ambulatory care organizations involved in ACOs with other healthcare organizations continue to support patient care during this challenging time, focusing on the safety and social distancing of patients and providers while CMS value-based reporting initiatives remain paused. This temporary relaxation of ACO reporting requirements allowed for an analysis of the literature to identify cost reducers and influencers attributed to ACO participation for outpatient organizations. While many outpatient organization characteristics may never return to pre-pandemic norms, this research utilized the quality reporting changes to identify what did work to control ACO-related costs, as well as what attributed to increased organizational costs.
Better (increased) coordination of patient care management initiatives, increased use of health information technology resources, and outpatient organization ownership models not associated with hospitals and/or ACO-participating hospitals are observations that have demonstrated a reduction of costs for outpatient organizations participating in ACOs. The presence and influence of social determinants of health and environmental conditions have been a contributing factor of increased costs to the outpatient organization in the ACO quality reimbursement environment. A lack of process and integration across ACOparticipating organizations, as well as misaligned financial incentives for both providers and their organizations have also led to increased costs. As the U.S. works to control the spread of COVID-19 by way of vaccination and herd immunity, ambulatory care organization leaders are encouraged to reflect upon these ACO-related cost reduction and influencer practices as clinic practices begin their return to routine operations.
Author Contributions: All authors contributed to this review in accordance with ICMJE standards. C.L. and E.W. contributed to investigation into the research topic, participation in the method, and original drafting of the manuscript. In addition to the initial screening and manuscript review/construct identification, T.M. contributed to the discussion/analysis, while also overall editing of the manuscript. All authors have read and agreed to the published version of the manuscript.
Funding: This research received no external funding.