Measurement Issues: Assessing Adherence and Disease and Health Outcomes
It is vital to assess adherence because adherence failure is a ubiquitous problem that directly impacts the health and well-being of children. This chapter will expand on reasons why to assess adherence, as well as, what is to be assessed, who should be assessed (and who should do the assessment), and how to assess. Because there is no ideal measure of adherence, the most common methodological limitations and problems (such as measurement reactivity) will be reviewed and strategies for minimizing their impact will be offered. Medical outcomes (such as glycosylated hemoglobin levels in patients with diabetes) are often treated as indirect measures of adherence, even though they are separate phenomena with a variable and conditional relationship to adherence. Measures of disease or health-status outcomes, including quality of life measures, will be reviewed separately.