Introduction

Osteoporosis is common, affecting approximately 10 million people in the USA [1]. Half of all post-menopausal women will experience an osteoporotic fracture in their lifetime while an estimated 15% will sustain a hip fracture [2, 3]. The current incidence of osteoporotic fractures is estimated at 2 million per year; however, this number is expected to increase as our population ages [4]. While osteoporosis is largely asymptomatic until fracture occurs, the economic and health consequences of fragility fractures are substantial. The annual healthcare cost of osteoporotic fractures is projected to reach 25 billion US dollars by 2025 [4]. In addition, fragility fractures are associated with poor health outcomes including decreased quality of life (QOL), reduced physical function and independence, and increased mortality [5,6,7,8]. Hip fractures in particular contribute to excess morbidity and mortality, as they are associated with an estimated 1-year mortality of 20–30% and requirement for long-term care in 25% of those who survive [9].

Given that osteoporosis is highly prevalent among post-menopausal women and is a treatable condition, the United States Preventive Services Task Force (USPTF) recommends universal screening for all women aged 65 and older with dual-energy X-ray absorptiometry (DXA) [10]. Similar recommendations for screening among postmenopausal women are endorsed by the National Osteoporosis Foundation (NOF) and American Association of Clinical Endocrinologists (AACE) clinical guidelines [11, 12]. Among men and women that have experienced a fragility fracture, bone mineral density (BMD) testing with DXA and treatment with osteoporosis pharmacotherapy is recommended for secondary prevention. Because falls contribute to a majority of fragility fractures, fall prevention is also a focus of care guidelines: the American Geriatric Society (AGS) guidelines recommend annual fall screening in all adults 65 and older, whereas the USPTF recommends selectively offering fall risk assessment and intervention to older adults at increased risk for falls. The USPTF highlights that more studies are needed to validate primary care tools to identify older adults at increased risk for falls and does not provide recommendations regarding routine screening. Falls, like many geriatric syndromes, are complex clinical problems with multiple underlying contributors; thus preventing falls necessitates multifactorial interventions [13,14,15,16].

Despite evidence-based guidelines and expanding treatment options for management of osteoporosis, many patients do not receive the recommended standard of care in the USA. To assess the extent of these gaps, the National Committee for Quality Assurance (NCQA) has developed quality measures that pertain to each of the areas of care defined by guidelines, including screening for osteoporosis, osteoporosis management following fragility fracture, and fall prevention. Some areas of care contain multiple indicators, such as post-fracture care where communication with the primary provider and BMD test or prescription for osteoporosis medication are independently assessed as high priority process measures (see Table 1). Most of these indicators are endorsed by the independent nonprofit organization National Quality Forum (NQF), which uses a consensus-based process to evaluate measures and shares the NCQA’s mission of enhancing quality and performance of health care delivered across the USA. Performance on these measures is reported through the Healthcare Effectiveness Data and Information Set (HEDIS) and these data are used to benchmark performance for accreditation and pay-for-performance programs. Beginning in 2015, under the Merit-based Incentive Payment System (MIPS), individual providers and practices have been incentivized to report performance on quality measures, including the NCQA osteoporosis measures, to the Centers for Medicare and Medicaid Services (CMS) for value-based payment incentives [22]. A significant number of quality improvement initiatives have been developed, in part in response to these financial incentives. Notably, under the MIPS program, practices can select which of at least six quality measures to report, and thus are more likely to choose metrics for which they believe they are performing well on.

Table 1 Osteoporosis-related quality measures used by Centers for Medicare and Medicaid and eligible for Merit-based Incentive Payment System
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The purpose of this review was to summarize current performance for osteoporosis quality measures used by CMS in pay-for-performance programs and to describe recent quality improvement strategies around these measures.

Methods

We reviewed recent literature addressing US performance on the osteoporosis quality measures endorsed by CMS and quality improvement initiatives targeting these measures. Measures were identified by review of the CMS website [23]. First, in order to describe current performance for osteoporosis quality measures, we identified the most currently available performance based on HEDIS and CMS’s former quality improvement incentive program Physician Quality Reporting System (PQRS) reports for each measure [17, 18, 20, 21]. Second, we performed a literature search (1) to identify reports of performance on quality measures outside of the HEDIS program and (2) to identify quality improvement interventions related to osteoporosis care. Using PubMed, Embase, and Web of Science databases from 2014 to 2019 and search terms listed in the Appendix, we identified 362 unique entries pertaining to our topic of interest which were reviewed by two reviewers (SDF and SC), with any discrepancies resolved by discussion with a third reviewer (GS). Additional manuscripts were selected by examining citation lists from papers identified through the structured search. Studies were included if the performance evaluation or quality improvement intervention were clearly described and addressed existing MIPS quality measures in the ambulatory setting for osteoporosis screening and falls prevention or for post-fracture care in any setting. Studies were excluded if they were not published in English or reported on fewer than 50 patients. Ultimately, 37 studies were included and summarized below.

Results

Current Performance on Osteoporosis Quality Measures

In the following section, we summarize performance for the quality indicators for osteoporosis screening, fragility fractures and secondary prevention, and fall prevention in the USA from HEDIS and PQRS as well as other studies using data from administrative sources or chart review.

Osteoporosis Screening

Since 2007, the National Quality Forum (NQF) has endorsed a measure evaluating the percentage of women aged 65–85 years who ever had a DXA to screen for osteoporosis (Table 1). In addition, CMS has developed a measure of over-use of DXA scanning in women under 65 years old who do not meet the risk factor profile for osteoporotic fracture.

Performance on Quality Measures Based on HEDIS and PQRS Reports

Early literature from 1999 to 2005 identified significant performance gaps in this area, with only 30% of female Medicare beneficiaries ≥ 65 years old having received a DXA scan ever [24]. Since then, the Affordable Care Act was passed, requiring private insurance plans to cover recommended preventive services such as osteoporosis screening for postmenopausal women without patient cost-sharing. Based on more recent estimates from HEDIS for Medicare HMO beneficiaries, there has been nearly a 10% increase in the DXA testing rate between 2006 and 2016, with 2016 estimates reaching 72.7% (Table 1) [17]. This is similar to estimates from voluntary reporting to CMS through PQRS in 2009–2012 [18]. The appropriateness measure is not included in HEDIS or PQRS, so estimates of performance are not available.

Performance on Quality Measures Based on Other Sources

Our review found three recent studies around screening patterns for osteoporosis (Table 2). Amarnath et al. evaluated the rate of DXA screening among over 50,000 women seen in university-affiliated primary care clinics in Northern California using electronic health record (EHR) data and a radiology database [25•]. Gillespie et al. evaluated DXA rates among women without history of osteoporosis or hip fracture using claims data for 2 million privately insured women [26••]. Both studies showed persistent gaps in osteoporosis screening, with DXA rates ranging from 30 to 60% depending on the age group studied. Patient-level predictors of poor utilization of DXA screening included low socioeconomic status (SES), black race, advanced age (i.e., age ≥ 75 or ≥ 80), and decreased utilization or primary care [25•, 26••]. Disparities based on SES seemed to narrow over time [26••].

Table 2 Recent studies evaluating performance gaps for osteoporosis measures
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Conversely, significant over-use of DXA in younger women was found in the study by Amarnath et al., with around 50% of women between 50 and 65 years old without any osteoporosis risk factors seen in primary care clinics having received a DXA [25•]. Overutilization of BMD testing was included in the Top 5 List of the American Board of Internal Medicine (ABIM) Choosing Wisely Campaign of practices to avoid due to lack of cost-effectiveness [40]. Despite the efforts of this campaign, another recent retrospective study of 34 practices affiliated with an academic center found that the rate of DXA in women < 65 years old without risk factors for osteoporosis before and after the DXA Choosing Wisely recommendation was unchanged at around 3.0% [27].

These studies suggest that patient barriers to appropriate screening and health system issues contribute to patterns of underscreening and overscreening and should be addressed in designing population level interventions to enhance quality of care and decrease disparities.

Fragility Fractures and Secondary Prevention

The NCQA process measures pertaining to adults with fragility fracture focus on secondary prevention of fractures through appropriate diagnosis and treatment of osteoporosis (Table 1). The first measure defines the proportion of women with a new fracture who received either a BMD test or prescription for an osteoporosis medication within 6 months of their fracture and has been endorsed by the NQF since 2009. The second measure evaluates the rate of documentation of communication between the provider treating fragility fracture and the primary provider responsible for ongoing care.

Performance on Quality Measure Based on HEDIS and PQRS Reports

There was a modest improvement in performance on the HEDIS quality measure for post-fracture care from 2007 to 2017 (Table 1) [17], though significant underperformance persists with 2017 estimates reaching 39.1% for Medicare PPO and 46.7% for Medicare HMO beneficiaries. Performance documented in PQRS for the years 2009–2012 ranged from 56.5 to 70.6%, though in 2012 only 204,369 eligible providers (0.8%) chose to report on this measure in PQRS [18]. We did not find performance data for documentation of communication with primary care providers following a fracture event.

Performance on Quality Measure Based on Other Sources

Our review found 11 recent studies evaluating quality in post-fracture care (Table 2). A majority of these studies used claims data to assess performance. There is clear unmet need for both diagnosis and treatment following fragility fractures, with rates of pharmacotherapy after fragility fracture hovering around 25%. Notably, there was a significant decline in osteoporosis medication use in the first decade of the 2000s that was evident across multiple studies [28, 29••, 32••, 36••]. Advanced age, male gender, lower SES, and higher comorbidity are potential risk factors for poor utilization of osteoporosis medication post-fracture [29••, 36••, 37]. Conversely, receipt of primary care, baseline history of osteoporosis, or prior osteoporosis medication use were associated with higher likelihood of receiving osteoporosis pharmacotherapy post-fracture [29••, 30, 36••]. Osteoporosis medication use prior to fracture was the greatest predictor of osteoporosis medication use after fracture [29••, 37••]. Not surprisingly, having a BMD test has also been shown to be associated with increased odds of bisphosphonate treatment after fragility fracture in the setting of a quality improvement RCT [41]. Poor adherence to osteoporosis treatment was observed in studies that measured medication possession ratio using dispensed prescription data [30, 31]. Overall, the recent literature points to a significant missed opportunity for osteoporosis care following fragility fractures, with a treatment gap that widened over the preceding decade.

Fall Prevention

Although approximately one-third of adults age 65 and older will experience at least one fall per year [42], less than half of these patients seek care after falls or discuss fall prevention with their provider [43]. The NCQA quality measures attempt to capture the percentage of older patients screened for fall risk and the percentage of patients with history of falls that had a fall risk assessment and documentation of a plan of care (Table 1).

Performance on Quality Measure Based on HEDIS and PQRS Reports

Among Medicare beneficiaries, 32.7–37.6% of patients with a history of falls had a fall risk assessment completed and 54.1–60.1% had a plan of care for falls documented in 2016 based on HEDIS estimates (Table 1) [21]. Higher performance was seen through PQRS voluntary reporting, though few providers reported on these measures [20].

Performance on Quality Measure Based on Other Sources

An older study of the US Medicare Current Beneficiary Survey suggests that fall risks among older patients are not being adequately addressed in clinical practice [43]. In that study, 22% of beneficiaries experienced a fall in the prior year; however, less than half of these individuals talked to a healthcare provider about falls and only 31% of women and 24% of men discussed fall prevention. Our review found one more recent study around fall care, which also utilized survey data to estimate the prevalence of falls and measures to address fall risk (Table 2) [39•]. This study found that patients with a history of falls are still not consistently receiving professional recommendations for fall prevention. Among adults aged 65 and older who responded to the 2011–2012 California Health Interview Survey, 12.2% reported multiple falls in the prior year but only 38.9% of those individuals had discussed how to avoid falls with a physician [39•]. Prior reviews also highlight gaps in fall prevention efforts [44]. A recent analysis comparing self-reported fall-related injuries to administratively obtained fall-related injuries from Medicare claims data suggests that falls continue to be underreported, which is important to recognize and address for preventive efforts [45]. Overall, recent literature suggests most patients with history of falls—those at highest risk for future falls—never discuss them with a medical provider nor receive recommended interventions for fall prevention. However, large population-based studies evaluating current performance for fall screening and prevention measures are lacking.

Quality Improvement Interventions in Osteoporosis

In the following section, we summarize recently published quality improvement interventions for the quality indicators for osteoporosis screening, secondary prevention of fragility fractures, and fall prevention and describe some of the challenges of translating evidence into real-world clinical practice.

Osteoporosis Screening

Our review found five recent studies describing quality improvement interventions for osteoporosis screening (Table 3), including two systematic reviews with meta-analysis assessing a range of provider, patient, and health system interventions, two RCTs of QI interventions targeting patient activation, and a study of a national QI program incorporating patient-specific prescriber feedback and education targeting providers and patients [46, 47, 48•, 49, 50•].

Table 3 Recent QI interventions for quality measure: BMD screening
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Consistent with prior work, studies in our review suggest that neither patient nor provider education initiatives consistently increase rates of diagnosis or treatment of osteoporosis [51, 52]. While education alone seems to have limited capacity for promoting practice change, when incorporated into complex interventions with multiple targets or with provider feedback and follow-up, education may improve BMD screening [48•, 50•]. Patient and provider-directed interventions that incorporate activation strategies for patients to discuss BMD testing with their provider or alerts for primary care providers with patient-specific feedback also show promise [47, 49], with provider-directed intervention likely having the largest impact on increase in DXA screening rates [49]. Innovative approaches to automation or engagement of ancillary staff in DXA ordering may also prove beneficial in this area [53]. In another study from Kaiser, invitation for self-referral for DXA among women 65 and older without recent screening led to a fivefold increase in completion rates [46]. While self-referral is a creative approach to removing barriers to screening, it is unlikely that this strategy is generalizable to implementation in an open healthcare system given the added complexity of reimbursement for DXA among mixed payers.

Fragility Fractures and Secondary Prevention

Our review found nine recent studies describing quality improvement interventions around post-fracture care (Table 4). Several studies document the importance of communication between the emergency room or inpatient provider taking care of a patient with fragility fracture and the primary provider managing ongoing care as an outpatient as a crucial component to improving the diagnosis and treatment of osteoporosis [63], though it is unclear how often this is performed.

Table 4 Recent QI interventions for quality measure: BMD test or OP treatment following fragility fracture
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Several models for collaborative care with a systems-based approach have demonstrated efficacy in improving post-fracture osteoporosis care, including ortho-geriatric services [64], auto-consultation of specialists dedicated to bone health [54], having a dedicated case manager focused on coordination of osteoporosis care [57], and fracture liaison services. On the other hand, electronic health record (EHR)-based intervention using an osteoporosis order set appears to have limited ability on its own to improve rates of BMD testing or osteoporosis treatment [65].

Arguably the most effective and well-studied quality intervention for post-fracture care is implementation of a fracture liaison service or other coordinator-based system with dedicated personnel to help to address fragmentation of care [55•, 56, 57, 59, 61, 62•, 64]. A meta-analysis by Nayak et al. suggested multiple effective strategies for improving BMD testing post-fracture, including fracture liaison service (FLS) or dedicated case manager, multifaceted intervention targeting patients and providers, and patient education or activation [62•]. However, osteoporosis treatment was only increased with FLS/case management or multifaceted interventions targeting patients and providers [62•]. A study of two FLS models at separate academic institutions participating in American Orthopedics Association’s national QI program suggested that the FLS model that implemented immediate care, including initiation of pharmacologic therapy during hospitalization, had better rates of osteoporosis treatment within 6 months of fracture compared with the model where recommendations were communicated to the primary care physician after discharge (67% vs. 30%, p < 0.001) [66]. This finding that FLS models that identify, diagnose, and initiate pharmacotherapy are more effective than models that rely on the primary care physician is corroborated by a meta-analysis and a recent study that compared a NP-led fracture liaison service to a physician-led fracture prevention program [56, 67]. Rates of DXA completion were similar in the two programs, but osteoporosis medication initiation was higher with the physician-led fracture prevention program where the coordinator had the ability to place orders as opposed to only communicate recommendations. Quality standards for fracture liaison services have now been proposed by the International Osteoporosis Foundation (IOF) as a tool for benchmarking performance, with the Capture the Fracture Best Practice Framework [68, 69].

Despite the potential benefits of a fracture liaison services, they have not been widely implemented in the USA. Several organizations including the American Orthopedic Association, the American Society for Bone and Mineral Research Task Force on Secondary Fracture Prevention, and the National Bone Health Alliance have ongoing initiatives to promote adoption of FLS. Future studies should evaluate if these efforts translate into uptake and maintenance of sustainable FLS programs.

Fall Prevention

Exercise-based interventions as well as multifactorial interventions with fall risk assessment and customized treatment tailored to address individual risk factors have been shown to be effective for fall prevention [14, 16, 70]. However, implementation of fall prevention interventions in non-research settings has had variable success. Our review found eight recent studies describing quality improvement interventions around fall prevention (Table 5). The CDC Stopping Elderly Accidents, Deaths, and Injuries (STEADI) initiative launched in 2012 with a toolkit to incorporate American Geriatric Society (AGS) clinical practice guidelines for fall prevention into primary care [79]. Implementation of the STEADI approach has been shown to be feasible in two large academic primary care clinics with early successes in increasing rates of fall screening [73, 74•]. The STEADI approach was also incorporated into a QI program among interprofessional teams in the ambulatory and long-term care setting in North Carolina that used education workshops to increase adoption of fall screening and prevention strategies [75].

Table 5 Recent QI interventions for quality measure: fall prevention
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Another successful model for quality improvement for geriatric conditions including falls is the Assessing Care of Vulnerable Elders (ACOVE) clinical practice model [80]. This model promotes clinical practice redesign with multicomponent intervention including nursing prescreening for falls, prompts and decisional support for providers, and educational materials for patients. The model emphasizes case finding, delegated clinical data collection by office staff, structured visit notes, and patient and physician education. Implementation of ACOVE led to 60% of patients at intervention sites receiving recommended care for falls vs. 37.6% of patients at control sites in one study (p < 0.001) [81]. Further analysis of ACOVE interventions for practice improvement of geriatric conditions suggests that delegation of selected tasks to non-physician healthcare providers is associated with higher quality of care [80, 82•]. Other studies also show improvement with pre-visit screening by ancillary medical staff [78•], emphasizing the benefit of multidisciplinary quality improvement teams and including non-physicians in clinical workflow, particularly for point-of-care measures like falls screening. Team-based care is also a pillar of high-performing primary care [83].

Because most of the evidence regarding fall risk assessment and intervention has been developed for primary care practice, it is unclear how best to implement these in other settings such as the emergency room or care in the community. However, given that emergency room physicians and paramedics are often first-line health care professionals to manage falls, care delivered in these settings represents an opportunity for intervention [84, 85]. Attempts at delivering interventions by paramedics and ER physicians with referral pathways for community-based fall services have been met with variable success [86,87,88]. More work is needed to define reliable and feasible means of identifying high-risk fallers and effective interventions in the emergency care setting.

Quality improvement interventions for falls, regardless of the setting, are resource intensive and further studies are needed to understand what elements are key to success. The time required for screening and intervention and issues around reimbursement are potential barriers to wider implementation of sustainable quality interventions in this area.

Discussion

In this review, we provide an update on current performance for osteoporosis quality measures used by CMS for pay-for-performance programs such as MIPS, and describe recent quality improvement strategies around these measures. Based on HEDIS reporting, we found that performance on measures in the managed care population showed gradual improvement in osteoporosis screening, identification and treatment following fragility fracture, and documentation of fall risk assessment and plan of care between 2006 and 2016. However, evidence from population-based studies suggested achievement for these process measures was lower where reporting was not mandated; performance gaps remain, particularly for post-fracture care. The discrepancy between performance assessed by CMS through PQRS or MIPS and population-based studies is likely explained by the fact that practices can select which measures to report for pay-for-performance programs and are more likely to choose areas where they already excel.

We also summarize a series of recent quality improvement initiatives around osteoporosis care. As has been shown for other areas of health care that require complex behavior change, passive intervention with education alone is not sufficient for improving quality of care for osteoporosis [89]. Interventions targeting the healthcare system, the provider, and the patient have all been studied with varying degrees of success for osteoporosis measures, though in general, greater efficacy has been demonstrated for multifaceted interventions that engage multiple stakeholders in the care process.

Areas for Future Work

  1. 1.

    Defining outcome measures in osteoporosis: Current quality measures for osteoporosis management and fall prevention are all process measures focused on the appropriate delivery of care. Process measures are typically more actionable, measurable in real-time, and make it easier to hold providers accountable compared to outcome measures. Ultimately, the goal of these processes is to improve health outcomes, and process measures require a strong process-outcome link in order to justify their use and the resource investment required for their continued measurement.

Direct evidence for the benefit of osteoporosis and fall prevention process measures in relationship to fracture outcomes is limited. Two recent large RCTs examined community-based osteoporosis screening interventions, one which found no reduction in major osteoporotic fractures and the other which found a small absolute reduction in hip fractures over 5 years of follow up [90, 91]. When evaluating the efficacy of screening for preventing fracture outcomes, it is important to consider that strategies that are effective for improving rates of BMD testing still may not improve treatment rates [92]. Data is also limited for fracture liaison services and subsequent fracture outcomes [93, 94]. A recent study of FLS across several UK hospitals found no difference in time to second fracture with implementation of FLS, though 30-day and 1-year morality were improved [64]. Lastly, a study of a multicomponent intervention for fall prevention showed no difference in fall-related injuries despite improving the care of falls [72•]. Overall incidence of falls requiring emergency room visit or hospitalization was similarly unchanged in another study of an intervention despite improved performance on fall process measures [71]. All together, these data remind us that processes of care may be necessary but not sufficient for reduction in osteoporotic fractures and falls.

  1. 2.

    Improving information capture for effective quality measurement: While quality measurement and value-based payment models hold great promise for improving adherence to standards of care, they also have led to increased demands on health systems and providers to collect performance data for reporting. A reliable, accurate, and feasible approach to identify patients in both the denominator and numerator for quality measures is essential. However, the electronic specification of the denominator and numerator both represent unique challenges from the perspective of cost and precision.

For example, fall-related quality measures rely on identification of patients at high risk for falls in the denominator; however, because falls are underreported, an EHR or claims-based history of falls alone would under-ascertain the at-risk population [43, 45]. Consensus around the use of tools for fall screening are lacking, making consistent, structured documentation difficult [13]. The use of natural language processing and machine learning approaches in the electronic specification of quality measures is starting to be explored [95, 96]. For example, Zhu et al. used natural language processing to identify fall risk screenings not documented by administrative codes; they found that 43% of patients had fall screening documented only in clinical notes but not coded in administrative data [97]. In the future, leveraging electronic health record-based data extraction using unstructured data may reduce the burden of data collection on the providers of care.

  1. 3.

    Capturing information on patient preferences: The ability to capture reasons why care is not provided is a valuable tool for quality measurement and can help to inform QI interventions. A study using a random 5% sample of US Medicare claims-based reporting data for PQRS osteoporosis quality measures evaluated physician-reported reasons for not providing recommended care with DXA screen or prescription for osteoporosis medication [98]. The authors found that 24% of claims documented that care was considered but not provided because care was either not indicated for a medical reason (e.g., comorbidity contraindication; 6.4%), patient reason (e.g., refusal; 4.1%), system reason (e.g., cost; 1.6%), or could not be provided for another reason (12.9%). These findings indicate that it may be difficult to improve performance on such a measure much higher than 75%. Future studies should continue to evaluate patient and systems reasons associated with missed quality measures in an effort to address modifiable risk factors. Shared decision making is an integral part of delivering high-quality care, and patient willingness to undergo and sustain treatment may need to be accounted for in any osteoporosis-related outcome measures that are developed.

  1. 4.

    Addressing the cost-effectiveness of quality measurement and quality improvement: Although often under-appreciated, the cost-effectiveness of quality measurement and quality improvement interventions are inherent in our conception of them as value-adding [99]. This issue of provider burden of documentation has to date not been addressed for osteoporosis quality measures, save for several evaluations of the cost-effectiveness of fracture liaison services [98, 100,101,102, 103••]. Overall, these studies have found that fracture liaison services ultimately result in cost savings, though the upfront investment of hiring dedicated staff for FLS may be a barrier to implementation in an open healthcare system with a mixed-payment model. These cost-effectiveness analyses are an important part of the equation for determining success of quality improvement strategies based not only on outcomes achieved but also value provided, and thus the willingness of healthcare systems to pay for their implementation.

In summary, the NCQA and MIPS measures for osteoporosis screening, secondary prevention after fragility fracture, and fall prevention are supported by strong evidence-based guidelines and qualify for value-based incentives through CMS. Over the last decade of measurement, the care of osteoporosis and falls has improved, though persistent performance gaps warrant investment in refining quality improvement interventions that impact process measures and clinical outcomes. Multifactorial and systems-based interventions likely have the greatest potential for impacting measurable change. As much as possible, systems that facilitate accuracy and ease of measurement should be further developed to address the reality of practice limitations, including cost and time required for quality measurement.