Performance measures (PMs; also known as quality measures, quality indicators, key performance indicators, or clinical quality measures) are criteria that are used to assess the performance of a service or a component of the service. The provision of high-quality, patient-centered endoscopic care is complex, involving a multidisciplinary team, many detailed processes, and an array of specialist equipment to investigate and treat a wide range of people of differing age and comorbidity with differing levels of urgency. PMs can be used to measure all aspects (often called “domains”) of the endoscopic service, from preprocedure, through the procedure itself, and in the postprocedural period. Examples of domains include timeliness, completeness of procedure, identification of pathology, management of pathology, complications, and patient experience. Ideally, a small number of PMs should be used to assess each domain: used together, they provide a global overview of the quality of the service. A good example of this process is the Endoscopy Global Rating Scale (GRS) used in the United Kingdom, which is now adopted in many other nations (
Fig. 9.1 The Endoscopy Global Rating Scale.
Fig. 9.2 An example of an endoscopy checklist.33
PMs can be categorized as outcome measures, structural measures, or process measures. Outcome measures assess the results of clinically meaningful aspects of care directly, and are usually considered the most important measures—for example, the pancreatitis rate following ERCP. However, it may not always be feasible to measure such outcomes—the data may be too difficult to capture, the event may be rare and therefore difficult to analyze with statistical certainty, or the timeframe to capture such data may be too long for it to be a useful measure of current performance (e.g., PCCRC rates, where several years need to pass before the true figure can be calculated). In these situations, the use of surrogate PMs may be required. These may also be outcome measures—for example, ADR is used as a surrogate for PCCRC rate. Where surrogate measures are used, it is desirable that there is evidence of a correlation between these measures and an important health outcome—reassuringly, in this example, there is increasingly compelling evidence demonstrating a strong correlation between an individual endoscopist’s ADR and its PCCRC rate.23,24 Surrogate measures may also be structural measures, which look at aspects of health care infrastructure (e.g., information about staffing levels or whether a provider has an electronic endoscopy reporting system), or process measures, which measure whether specific quality actions are being implemented (e.g., the proportion of patients that have had a preprocedure endoscopy checklist completed;
Colorectal cancer screening has facilitated the implementation of PMs for diagnostic colonoscopy. However, measures for therapeutic colonoscopy and for most other aspects of GI endoscopy are either nonexistent or very much in their infancy.
It is usually desirable to identify a minimum standard and a target standard for each PM. Although PMs will remain relatively static over time, quality improvement is a dynamic process and as such the standards within such measures will usually increase over time as techniques and technologies improve. The standards may also vary according to the specific procedure—for example, the minimum standard for ADR will be higher for fecal occult blood diagnostic colonoscopy compared to screening colonoscopy. At present, there are many PMs where no evidence-based minimum standard has been defined. With time, further research can help determine what the appropriate standards should be; nevertheless, in the interim it may still be useful to measure and benchmark performance against other similar services.
An example of endoscopic PMs is given in
Fig. 9.3 American Society for Gastrointestinal Endoscopy (ASGE) performance measures for ERCP.34
9.3 Practicalities of Measurement
PMs should enable assessors to identify specific deficits in the service, permitting them to be addressed and thus resulting in better patient outcomes. Several different attributes should be considered when constructing PMs:
9.3.1 Clinical Importance
As described earlier, PMs should correlate with important health outcomes. Measures should be as evidence-based as possible. However, current evidence for most endoscopic PMs (and particularly for minimum standards) is low—further research is required, but in the meantime, expert consensus opinion is an appropriate interim approach to ensure that PMs are clinically meaningful for their target audience.
9.3.2 Standardization
The standardization of PM definitions and methodology of measurement is important to permit meaningful comparison between individuals and services. PMs should be as objective (such as using an unadjusted cecal intubation rate—unadjusted for strictures or poor bowel preparation) and reproducible as possible. Current endoscopic PM definitions and methodology calculations are poorly described and inconsistent, although there is welcome movement to correct this by producing international standards.27 Another component that requires standardization is in the robustness of the methodology for capturing complications—otherwise, a perverse situation arises where poor services may appear to perform better, simply because they have not identified the complications that have occurred.
Different PMs lend themselves to different methodologies. PMs based on common events such as cannulation of the intended duct at ERCP, or adenoma detection at colonoscopy, are suited to quantitative analysis. However, rarer events, such as missed cancer or endoscopic perforation, may be best examined by qualitative review of each adverse event (root cause analysis). Rarer events can also be examined at an endoscopy unit level rather than endoscopist level, although this methodology can sometimes overlook poorly performing individuals.
9.3.3 Practicality
The trade-off of all PMs is the practicality of capturing and analyzing the data. While a multitude of highly complex PMs may be justifiable on quality grounds, it may be unrealistic or impossible to implement such measures in a busy service. Considerations include the number of PMs, the number of data sources required to calculate the PM (e.g., ADR requires both pathology and endoscopy data, whereas polypectomy rate does not), and whether data are stored electronically or not—electronic endoscopy reporting systems are an important component in allowing timely data collection and automated, standardized PM reporting.
9.3.4 Governance Infrastructure
The practicality and objectivity of quality assurance (QA) is influenced greatly by the governance infrastructure. QA requires