WHAT IS THE EVIDENCE THAT QI INITIATIVES IMPROVE OUTCOMES IN CAP?

5. WHAT IS THE EVIDENCE THAT QI INITIATIVES IMPROVE OUTCOMES IN CAP?

While it may be necessary to extrapolate improvements in evidence-based process of care measures to clinical, patient-based and economic outcomes, most patients, physicians, and policy-makers would prefer to see “hard evidence.”

50 Gavin Barlow This section will review the evidence that QI interventions improve outcomes

in CAP.

5.1. Clinical outcomes

Relatively few studies have shown any change in clinical outcomes follow- ing the implementation of a CAP QI initiative. This is probably due to the large amounts of data required to demonstrate clinically important changes in “traditional” clinical endpoints, for example, mortality. An exception to this was a study that used statewide databases to include 28,661 patients (Dean et al., 2001). Following implementation of a care pathway, 30-day mortality decreased from 13.4% to 11% in hospitalised patients managed by physicians affiliated to pathway using hospitals. During the corresponding period, mortality in patients managed by physicians affiliated to non-pathway hospitals increased from 13.2% to 14.2%. Al-Eidan et al. (2000) also demon- strated a significant reduction in “treatment failure” from 31% to 8%. How- ever, this result may have been biased by the use of a non-objective outcome measure. Mortality in the same study also decreased from 8% to 3%, but this was not statistically significant.

5.2. Patient-based outcomes

Clinical outcome measures provide important information to clinicians and policy-makers, but do not necessarily reflect aspects of outcome that are important to patients. Patient-based outcomes refer to measures of subjec- tive well-being, such as quality of life, symptoms and satisfaction with care. The widespread recognition of the need to evaluate the “complete state of physical, mental and social well-being and not merely the absence of disease or infirmity” (World Health Organisation, 1947) means that clinical audit and research is now considered inadequate if patients’ experiences of outcome have not been assessed. Few studies have used patient-based outcomes, how- ever, to measure the impact of a CAP QI intervention. Although Atlas et al. (1998) showed an increase in low-risk patients managed as outpatients, patients appeared to be less satisfied with care, as measured by a non-validated outcome measure, when compared to a comparable cohort from the Pneumonia Outcomes Research Team (PORT) study. In contrast, the cluster- randomised trial by Marrie et al. (2000) did not show any difference in patients’ quality of life (as measured by SF-36) between intervention and con- trol hospitals, despite a higher number of low-risk patients being managed as outpatients at intervention-using hospitals. There is currently no evidence therefore, to suggest that CAP QI initiatives improve patient-based outcomes.

Pneumonia Guidelines in Practice

51 The best evidence is that care pathways can be used to optimise resource use,

without affecting patients’ quality of life.

5.3. Economic outcomes

There have been no cost-effectiveness analyses of CAP QI initiatives.

A number of studies have shown decreases in either surrogate markers of resource use or direct healthcare costs. In the cluster-randomised trial by Marrie et al. (2000), bed-days per patient managed (BDPM), a surrogate marker of resource use, decreased from 4.4 to 6.1 days. In a subsequent eco- nomic paper, Palmer et al. (2000) found a cost saving per patient of between $457 and $994. Suchyta et al. (2001) demonstrated a reduction in mean anti- biotic costs (from $186 to $141) and direct costs per patient (from $678 to $319) as a result of an outpatient QI intervention. Al-Eidan et al. (2000) calcu- lated dramatic total cost savings, from £2024 to £1020 per patient, in the United Kingdom. In a small Australian study, which compared two hospitals using penicillin and cephalosporin-based antibiotic regimens, the antibiotic costs per patient were found to be lower in the hospital using penicillin, with- out an apparent impact on clinical outcomes (Dobbin et al., 2001).

The main problem with all of these studies, however, is that they fail to link the costs of developing the intervention, the direct costs of care (e.g., anti- biotics) and the indirect costs of CAP (e.g., time of work) with improvements in either provider (e.g., length of hospital stay) or patient status (e.g., quality of life). If the costs of the intervention and/or the direct costs as a result of it are high therefore, it is possible that the gain in terms of, for example, the cost per additional low-risk patient managed as an outpatient, may not be worthwhile. There is also concern that costs may simply be shifted from secondary to primary care.