Quality indicators and development targets in the national clinical quality registries in cancer care and screening.

WHAT IS ALREADY KNOWN ON THIS TOPIC

Danish clinical quality registries enable quality measurement and quality improvement, providing a link between advancing scientific evidence and applied clinical practice using quality indicators, some presented with a development target referred to as a ‘standard’.

WHAT THIS STUDY ADDS

Fulfilment of standards for clinical quality indicators varied in the Danish clinical quality registries in cancer care and screening, associated with differences in conservative or ambitious behaviour of the steering groups when defining the standards. The fulfilment of standards for clinical quality indicators was generally very high, and many standards were determined at a conservative level, leaving no room for measurable quality improvements.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

The Danish clinical quality registries in cancer care and screening could benefit from focusing the assessment of fulfilment of standards on designated development targets, achievable based on well-defined actions in clinical practice. More consensus regarding standard setting could enable comparison of clinical quality across the registries to establish an overview, allowing prioritising of resources and quality improvement attention across cancers.

Introduction

Cancer survival has improved considerably in high-income countries during the last three decades. 1 2 This has at least partly been driven by earlier detection and continuous advancements in diagnostics and treatments combined with attention to updated clinical guidelines and systematic quality of care improvement initiatives. 3 6 Clinical quality registries and quality indicators are tools for quality measurement and quality improvement, providing a link between advancing scientific evidence and applied clinical practice. 57 12 The Danish clinical quality registries comprise around 80 registries on clinical quality in multiple disease areas, monitoring patient-level information intended for quality improvement and research. 13 14 This includes 27 clinical quality registries in cancer care and screening united by the Danish Multidisciplinary Cancer Group. 6 The primary purpose of this infrastructure is to ensure continued improvement in the preparation of clinical guidelines, the quality of clinical processes, the promotion of knowledge dissemination and patient outcomes in the five geographical government-based regions in Denmark responsible for providing healthcare services for their residing populations. 613 15 Registrations in these registries are mandatory for all the relevant clinical departments and other service providers. 13 15 In each clinical quality registry, quality indicators may be presented with or without a defined development target, often referred to as a ‘standard’. 13 15 Standards for quality indicators should preferably be process- or result-orientated development targets, expected to be reachable within the near future. 13 16 Process-orientated quality indicators concern delivery of a specific procedure in a well-defined population, whereas result-orientated quality indicators evaluate the health status (eg, mortality) in the population. 13 16 17 Around 70% of the indicators in the Danish clinical quality registries have a defined standard. 13 The standards for clinical quality indicators are defined by the clinical steering group, commonly composed of relevant clinicians, specialists, Danish Clinical Quality Registry staff and patient representatives. 13 15 A standard may be defined conservatively or ambitiously, and fulfilment depends strongly on the attitude of the steering group and the balance between ambitious target setting and realism as to what is achievable. 13 14

The present study aimed to investigate the degree of fulfilment of standards for clinical quality indicators in the Danish clinical quality registries in cancer care and screening. This included fulfilment of standards for clinical quality indicators on national and regional levels in the three most recent reported years. Furthermore, the changes in fulfilment of standards for clinical quality indicators over time, the fulfilment of standards for specific process- or result-orientated clinical quality indicators, and the fulfilment of standards for clinical quality indicators in each of the five Danish regions were explored.

Methods

Study design

The present observational population-based nationwide study was based on data reported in the annual reports from the 27 Danish clinical quality registries in cancer care and screening. The most recent published report from each register was available for download on the website ( https://www.rkkp.dk/kvalitetsdatabaser/ ). 13 The published annual reports hold information on the proportion of individuals fulfilling each defined standard in the registries on national and regional levels including the last 3 years. 13 All data were accessed on aggregated level.

Setting

The Danish population in 2022 included 5.9 million inhabitants with a life expectancy of 80 years among men and 83 years among women. 18 The Danish healthcare system is tax-supported, financing approximately 85% of the total health expenditures, including free access to hospitals, outpatient clinics and general practice, as well as partial reimbursement of prescribed medication. The remaining patient co-payment primarily constitutes prescribed medications and dental care. 19 20 Since 2007, the Danish National Health Service has been separated into five regions: the Capital Region of Denmark, the Central Denmark Region, the Region of Southern Denmark, Region Zealand and the North Denmark Region. Each region runs the public hospitals and health services including the general practice. 19 21 Since 2011, the Danish Clinical Registries have coordinated the activities of a national quality improvement programme using nationwide clinical quality registries, primarily financed by the regions. 12 The primary objective is to facilitate surveillance and improve the quality of care. The registries are required to fulfil a set of national criteria regarding organisation, data safety and reporting. Hospitals and clinics are required to report details of all diagnosed patients to the registries, in order to facilitate nationwide collection and comparison of data for all the clinical quality indicators. All registries are required to produce an annual report with epidemiological and clinical interpretation of the data, including recommendations for quality improvement. 12 The Danish Multidisciplinary Cancer Group unites the clinical quality registries in cancer and contributes to the establishment and maintenance of evidence-based, national clinical guidelines, including diagnostics, treatment and rehabilitation. 6

Eligibility criteria and selection of indicators

The most recently published annual report for all the Danish clinical quality registries in cancer care and screening was downloaded on the 13 December 2023. The extraction of data was executed from the 13 December 2023 until the 5 February 2024. For an indicator to be included in the analysis, it had to fulfil certain criteria. The indicator should be presented in an indicator table, presenting the number of evaluated individuals (denominator), the number of individuals obtaining the indicator outcome (numerator) and the proportion of the evaluated individuals obtaining the indicator outcome. Indicators were excluded if no standard was presented, or the defined standard was presented as a range. Finally, the indicators should be evaluated in 12-month periods.

Data extraction

Information from indicator tables was extracted on the national and regional levels for each clinical quality registry, including indicator description, the defined standard, the desired direction of improvement, the last reported year for the indicator, numerator and denominator for the fulfilment of standards for clinical quality indicators the last reported year and proportion of individuals who fulfilled the standard in each of the last three reported years, whether the indicator was classified as a process or result indicator, whether the indicator was established or supplemental, the geographical region, and the role of the region (either responsible for the treatment or the place of residence). The classification of process and result indicators were extracted as defined in the reports. Indicators were defined as supplemental indicators if presented as supplemental indicators in the annual reports or if presented in the supplemental assessments of the annual reports. A few indicators in the annual reports from the clinical quality registries describe the data quality and completeness of the registry, rather than the quality of clinical practice. These were also included in the analysis. 11

Data analysis

Statistical analyses were performed in Stata 17 (StataCorp, 2021; Stata Statistical Software: Release 17; College Station, TX: StataCorp LLC). Characteristics of the data from each clinical quality registry were presented, including the year of the included annual report, the number of included indicators, regions, hospital departments, and individuals with cancer or invited to cancer screening. The overall fulfilment of standards for clinical quality indicators on the national and regional levels was computed, that is, the proportion of indicators that fulfilled the standards for all the clinical quality registries in cancer care and screening and the median and IQR of fulfilment according to the registries. The fulfilment of standards for clinical quality indicators was presented in bar charts as proportions of indicators that fulfilled the standards within each clinical quality registry, including the numerator and denominator of fulfilled standards in each registry. This evaluation was summarised at the national and regional levels, in total for the last three reported 12-month periods, and, separately, for each of the last three reported 12-month periods, to identify changes in the fulfilment of standards for clinical quality indicators within the registries. The fulfilment of standards was stratified to identify variation between process- and result-orientated quality indicators, established or supplemental indicators, and the five regions. Analyses were stratified according to registers evaluating cancer care or screening, to identify differences in fulfilment of standards for clinical quality indicators. Additionally, the proportions of indicators not fulfilling the defined standard within none to five regions, in which data was presented, were calculated. Missing data was handled as within each annual report.

Patient and public involvement

It was not appropriate or possible to involve patients or the public in the design, conduct, reporting or dissemination of the project.

Results

The 27 clinical quality registries in cancer care and screening contained 339 quality indicators. Of these, 123 indicators were excluded for different reasons: 63 had no defined standard, 3 presented a standard only as a range, 23 presented no proportion or number of individuals evaluated, and 34 were reported for a period longer than 12 months. Hence, 216 quality indicators were evaluated in the present study. The annual reports included information on 91 983 individuals with a registered cancer diagnosis and 1 506 093 individuals invited to a cancer screening. Some individuals are expected to reoccur in multiple clinical quality registries due to the overlapping inclusion criteria of the registries (eg, registration in both a screening registry, a cancer registry and the palliative care registry would be possible for some individuals). For 190 of the included indicators, the individuals were presented according to the region responsible for the cancer treatment. The remaining 26 indicators presented the individuals according to their region of residence. A short description of the data from each clinical quality registry is presented in table 1 .

The fulfilment of standards within each registry for all for clinical quality indicators summarised for the last 3 years is presented in figure 1 . On the national level, 75% of the indicator standards were fulfilled in the last three reported years (median 75%, IQR 64–90 according to the registries), and 25% were not fulfilled. On the regional level, 71% of the indicator standards were fulfilled in the last three reported years (median 75%, IQR 61–82 according to the registries), whereas 29% were not fulfilled. On the national level, all indicator standards in the last 3 years were fulfilled in four registries (the Danish Registry of Childhood Cancer, the Danish Melanoma Database, the Danish National Chronic Myeloid Neoplasia Registry and the Danish Pancreatic Cancer Database). On the regional level, nearly all indicator standards were also fulfilled in these four registries: 91%, 99%, 99% and 90%, respectively. Only two registries (the Danish Quality Database for Cervical Cancer Screening and the Danish Palliative Care Database) fulfilled less than 50% of the indicator standards in the last 3 years both on national and regional levels. The Danish Quality Database for Cervical Cancer Screening fulfilled the lowest proportion of indicator standards with only 5% on the national level and 12% on the regional level.

The 3-year changes in fulfilment of standards for clinical quality indicators for each registry are presented in figure 2 . The proportion of fulfilment of standards increased in seven registries on the national level and nine registries on the regional level. The proportion of fulfilled indicators decreased in 11 registries on the national level and 13 on the regional level. In the most recent year, 67% of the indicator standards (median 73%, IQR 50–91 according to the registries) were fulfilled on the national level, and 66% of the indicator standards (median 75%, IQR 50–83 according to the registries) were fulfilled on the regional level. In the second most recent year, 78% of the indicator standards (median 80%, IQR 67–100 according to the registries) were fulfilled on the national level, and 76% of the indicator standards (median 73%, IQR 68–88 according to the registries) were fulfilled on the regional level. In the third most recent year, 80% of the indicator standards (median 88%, IQR 67–100 according to the registries) were fulfilled on the national level, and 75% of the indicator standards (median 79%, IQR 70–88 according to the registries) were fulfilled on the regional level.

Figure 3 illustrates the analysis stratified according to the process or result orientation of the indicators and whether the indicator was supplemental. Among the quality indicators evaluated in this study, 76 were defined as process indicators, and 75 were defined as result indicators. Examples of identified process indicators from the Danish clinical quality registries in cancer care and screening were: (1) proportion of patients in the high-risk group being treated with surgery or radiotherapy within 180 days after the diagnosis (indicator 6 from the Danish Prostate Cancer Registry, defined standard ≥60%) and (2) proportion of individuals with a positive stool sample who are examined with a colonoscopy or CT-colonography (indicator 4 from The Danish Quality Database for Colon Cancer Screening, defined standard >85%). Examples of identified result indicators from the Danish clinical quality registries in cancer care and screening were: (1) proportion of patients with recurrence among the patients treated for disseminated disease (indicator 4 from the Danish Testicular Cancer Database, defined standard <15%) and (2) proportion of patient surviving 1 year from the first registered resection (indicator number IIb from the Danish Lung Cancer Registry, defined standard ≥90%). A total of 65% of the process indicator standards were fulfilled both on national and regional level, whereas, for the result indicator standards, 84% and 79% were fulfilled on national and regional levels, respectively.

Altogether, 196 of the evaluated indicators were established indicators, and 20 were supplemental indicators. For the established indicator standards, 77% and 73% were fulfilled on the national and regional levels, and for the supplemental indicator standards, 53% and 52% were fulfilled on the national and regional level, respectively.

The proportion of fulfilment of standards according to the region is presented in table 2 . In the Capital Region of Denmark and the Central Denmark Region, 72% of the indicator standards were fulfilled; in the Southern Region, 76% were fulfilled; in Region Zealand, 63% were fulfilled; and in the North Denmark Region, 71% were fulfilled. Fulfilment of standards for clinical quality indicators was higher in the subset where the recorded region was the treatment region than in the subset where it was the region of residence. The regional differences were major when restricting the analysis to the screening registers evaluated according to residence region; in this category, only 28% of the indicator standards were fulfilled in Region Zealand, 36% in the North Denmark Region, 39% in the Capital Region of Denmark, 50% in the Central Denmark Region and 53% in the Southern Region.

The number of regions in which each of the standards for clinical quality indicators was not fulfilled in each of the last 3 years was also evaluated. For the combined 3-year period, 43% of the standards were fulfilled in all registration regions for the specific quality indicators. Furthermore, 22% of the evaluated quality indicators were unfulfilled in only one region, 15% in two regions, 7% in three regions, 5% in four regions and 7% in five regions. These proportions were maintained over the evaluated 3-year period.

Discussion

This study evaluated 216 quality indicators from the Danish clinical quality registries in cancer care and screening. At the national and regional levels, 75% and 71% of the standards were fulfilled, respectively. The fulfilment of standards for clinical quality indicators varied between the 27 registries and decreased during the evaluated period. Standards were more often fulfilled for result-oriented indicators than those with a process-oriented scope and for established than supplemental indicators. Altogether, 43% of the standards were fulfilled in all registration regions for the specific indicator. The highest proportion of standards was fulfilled in the Region of Southern Denmark and the lowest proportion in the Region Zealand.

Attitude and behaviour of target setting

The variation in the proportion of fulfilment of standards for clinical quality indicators across the 27 Danish clinical quality registries in cancer care and screening mainly illustrates a variation in conservative or ambitious behaviour of the steering groups, when defining the standards for clinical quality indicators. The balance between a conservative or ambitious approach is struck differently by different steering groups. 13 15 Some registries are defining standards that are already fulfilled in one or more regions and are therefore theoretically reachable in the remaining regions, assuming that the population demographics are similar. On the other hand, the 43% of standards for clinical quality indicators that were fulfilled in all the registration regions represent a somewhat conservative approach to standard setting, leaving no room for the presentation of a quality improvement opportunity. 13 15 The identified variation in the proportion of fulfilment of standards for clinical quality indicators according to process- or result-orientated scope suggests that steering groups may be more willing to be ambitious regarding process indicators than for result indicators (which are often cancer survival). Processes to improve the fulfilment of process-oriented quality indicators include provision of higher or more specific clinical care to the relevant patients. The processes to improve the fulfilment of result-oriented quality indicator, similarly, include provision of higher or more specific clinical care to the specific patients, including improved expertise among the surgeons and radiologists. However, the fulfilment will only improve if the changes in clinical care imply better clinical outcomes. Hence, improving the outcome for a process-orientated quality indicator, such as an evidence-based procedure for a specific population, may appear less complex compared with improving a result-orientated quality indicator, such as reducing 1-year mortality in a population with multiple indirect pathways. 16 This difference in tangibleness may lead steering groups to adopt a more conservative approach towards the ambition level of standards for result-orientated clinical quality indicators or possible maintenance of annual presentation of quality indicators with standards approaching the upper or lower limit (eg, 30-day mortality <1%). Conversely, when defining standards for supplemental indicators (e.g. new indicators), steering groups tend to be more ambitious, or less certain about what is a realistic clinical development target, resulting in a lower proportion of fulfilment.

The 29% of standards for clinical quality indicators not met at the regional level in the present study represent the current potential for improvement in clinical processes and result outcomes. 7 10 It is uncertain what proportion of fulfilment of standards for clinical quality indicators is most optimal in the promotion of quality improvement, using the standards for clinical quality indicators as development targets, achievable in the near future. 13

Variation in clinical quality

Among the quality indicators with defined standards and potential for measurable improvement, some clinical quality registries represented an increase in the number of fulfilled standards over the investigated 3-year period. This supports the use of clinical quality registries and standards for clinical quality indicators to drive clinical quality improvements. However, more registries represented a decrease in the number of fulfilled standards with lower overall fulfilment across registries in the most recent year compared with the second and third most recent years. Thus, the clinical quality registries including clinically relevant quality indicators serve as instruments for quality measurement and improvement but also collect data on quality maintenance. 7 10 Some registries (the Danish National Acute Leukemia Registry, the Danish Database for Chronic Lymphocytic Leukemia, the Danish National Multiple Myeloma Registry and the Myelodysplastic Syndrome Database) reported data delivery issues in the most recent year, affecting this result. Hence, the decreased fulfilment of standards for clinical quality indicators cannot be interpreted as representing a decrease in clinical quality. In both scenarios where the standards are not or are already fulfilled, improvement in the quality indicators could occur without the standard value being crossed , making it invisible if the focus is exclusively on the fulfilment of standards. Hence, it is important to recognise that even though the proportion of fulfilment of standards in some registries did not increase, the quality of care according to the individual quality indicators may have improved over the period, potentially approaching the defined standards, and opposite.

The variation in fulfilment of standards for clinical quality indicators between the regions, with the highest fulfilment in the Region of Southern Denmark (76%) and lowest fulfilment in Region Zealand (63%), suggests the variation in the quality of care. However, this variation in fulfilment was largest in the standards for clinical quality indicators where the regions were classified according to the region of residence, with only 40% of the standards for clinical quality indicators being fulfilled in Region Zealand. This finding could be interpreted in multiple ways. The stratification according to the region responsible for the treatment or the patient’s place of residence is decided by the individual steering group. Some quality indicators are classified according to the region of residence due to the limited availability of specialised care in certain regions. Since results presented in the annual reports from the Danish clinical quality registries are unadjusted, the variation in fulfilment of standards for clinical quality indicators could originate from issues related to access to or transportation between residences and hospitals in a different region or possible casemix of the residents in the five Danish regions. 17 19 22 However, regional disparities in sociodemographic characteristics or comorbidities have not been established in previous studies. 19 22 23 All three quality registries in cancer screening presented fulfilment of standards for clinical quality indicators according to region of residence, and the proportion of fulfilled indicator standards was lowest across all regions when restricting the analysis to the screening registries evaluated according to residence region. Hence, variation in participation in cancer screening explains much of the identified variation in fulfilment of standards for clinical quality indicators according to region of residence. Nonetheless, the results from the present study indicate geographical variation in the quality of cancer care and screening in Denmark, with residents of Region Zealand receiving the lowest fulfilment of standards for clinical quality indicators.

Strength and limitations

The present study analysed aggregated population-based and nationwide data across all the Danish clinical quality registries in cancer care and screening, identifying fulfilment of standards for clinical quality indicators. This wide perspective has the major strength that the practice for defining standards for clinical quality indicators as possible development targets was measurable and comparable in all the Danish clinical quality registries in cancer care and screening, using proportions of fulfilment in annual reports based on mandatory registrations of data on all individuals with contacts at relevant clinical departments. 13 15 Similar clinical quality improvement monitoring initiatives exist in other healthcare systems, including the UK National Cancer Diagnosis Audit which evaluates quality improvement performing completion of audit cycles. 9 24 However, as in most healthcare systems, this audit does not present the same data completeness or continuous measurement of all individuals with a cancer diagnosis, and the idea of fulfilment of a development target is very prominent in the Danish healthcare setting. 9 15 24 To optimise data driven quality improvement, focusing on implementing the few most important procedures and interventions to improve specific clinical outcomes, could possibly be more effective for quality improvement, than the current complex structures of the Danish clinical quality registries in cancer care and screening. 8

The study also has some limitations. First, the clinical effects and evidence for quality indicators and standards could not be evaluated in the present study. Rather, the ambition level for the standards for clinical quality indicators was evaluated based on the registered delivered national and regional care for 3 years. Similarly, it was not possible to identify whether indicator standards were intended conservatively defined as a minimum level of quality for patient safety, rather than ambitious quality development targets. This could explain the rather high fulfilment of standards in some registries. However, this practice would not promote data-driven quality improvement. 13 14 Furthermore, possible changes in the specific population or definition of the indicator or the standard levels over time were not available in the present study, and high or low proportions of fulfilment of standards for clinical quality indicators were often seen in databases with relatively many or few indicators. However, analyses over the past three reported years were performed only according to the standard level reported in the most recent annual report at the time of data extraction. This could be interpreted as the most current target for good clinical quality, defined by the individual clinical steering groups. The high fulfilment of standards for clinical quality indicators across the registries according to the standard from the included annual reports does neither indicate recent upregulations of the ambition level of the standards. The present study is presented using a descriptive approach without formal statistical testing of the large number of variations between registries, indicator types and regions. However, the identified variations represent large differences in fulfilment of quality standards in the Danish clinical quality registries in cancer care and screening.

Conclusions

This study investigated the fulfilment of standards for clinical quality indicators in Danish clinical quality registries in cancer care and screening over the past 3 years, identifying variations in the extent to which these standards were met between the registries and indicator types. These results represent different approaches regarding the use of the indicator standards as conservative or ambitious development targets. Many of the registries have defined standards at a level where the standard is met in some or most of the regions, hereby possibly promoting regional data-driven quality improvement in clinical care in the regions where the standard has not yet been met. However, many standards were fulfilled across all regions, suggesting that no further measurable improvements in clinical quality were necessary according to the standard levels defined by the clinical steering group. The Danish clinical quality registries in cancer care and screening may benefit from focusing the assessment of fulfilment of standards for clinical quality indicators in the annual reports on a few selected quality indicators designated as development targets, which are expected to be achievable shortly based on defined actions in clinical practice. Still, traditional indicators without current quality improvement potential could be presented without a development target. The varying attitudes regarding target setting restrain possibilities for comparing the level of clinical quality across cancers, despite the strong infrastructure of the Danish clinical quality registries. This limits the possibilities of establishing an overview to enable the prioritising of resources and quality improvement attention across the cancers.

Funding: This study was funded by The Danish Cancer Society, grant number R305-A18514.

Data availability free text: Data from all historical annual reports are available upon reasonable personal request at https://rkkp.zendesk.com/hc/da/requests/new . Furthermore, the complete list describing the included 261 indicators is available in Danish upon request to the corresponding author.

Patient consent for publication: Not applicable.

Ethics approval: Not applicable.

Provenance and peer review: Not commissioned; externally peer-reviewed.

Patient and public involvement: Patients and/or the public were not involved in the design, conduct, reporting or dissemination plans of this research.

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Data availability statement

Data are available upon reasonable request.