The chapter also discusses different types of data relevant to patient care and their usefulness for evaluating the continuity (and quality) of HIV care and access to supportive services. The relative merits of each type of data are discussed, as well as whether the differences among data types (in particular claims data and clinical data) “encompass gaps in measures for HIV care” (statement of task question 1b). The chapter ends with the committee’s conclusions and recommendations for “the most critical data and indicators for gauging the impact of the National HIV/AIDS Strategy (ONAP, 2010) and the Patient Protection and Affordable Care Act [P.L. 111-148] in improving HIV/AIDS care.”
The Institute of Medicine (IOM) letter report Leading Health Indicators for Healthy People 2020 (IOM, 2011d, p. 8) defined the term “indicator” as “a measurement” and “leading health indicators” as “quantitative expressions of health-related concepts that reflect major public health concerns.” For the purposes of the present report, indicators of HIV care and access to supportive services are defined as quantitative expressions (measurements) pertaining to the state of HIV care and the availability of supportive services for PLWHA (and subgroups thereof) in the United States. “Core indicators” are those indicators deemed by the committee to be fundamental both to assessing the extent to which persons diagnosed with HIV are connected to appropriate medical care, are maintained in care over time, and have access to needed supportive services in the United States and to gauging the impact of the NHAS and the ACA in improving HIV/AIDS care.
Indicators may include process measures and outcome measures. Process measures pertain to processes of care, such as regular visits for routine care, lab tests and screening performed, and therapies initiated. Outcome measures pertain to the actual health outcomes or status of patients. Mortality and morbidity are ultimate outcome measures for tracking access to quality HIV care for people diagnosed with HIV. Intermediate outcome measures include CD4+ T-cell counts (CD4 counts) and plasma HIV RNA levels (viral loads), which reflect disease progression and infectivity. Process measures are important indicators of quality of care and treatments received, which research has shown are directly associated with good clinical outcomes (Kitahata, 1996; Kitahata et al., 2000, 2003; Landon et al., 2005). For example, regular monitoring of CD4 counts implies good-quality HIV care, with the expectation of good outcomes.
Indicators often are defined in terms of a percentage, proportion, or other relative measure and are not synonymous with the data elements