A CAUTIONARY NOTE: INCORRECT INTERPRETATIONS OF OUTCOME MEASURES
Sometimes even with diligence with respect to selection of outcome measures, the data collected from these measures can be misinterpreted. In intervention research, it is common practice to employ self-report measures because of time factors and ease of administration. One popular measure used with geriatric populations is the CES-D or the Geriatric Depression Scale. It certainly would be cost prohibitive to send trained geriatric psychiatrists into the homes of individuals for a 1-hour structured interview to assess depressive symptoms. However, it is important to recognize that these scales measure depressive symptoms and a high score, though certainly a reason for caution, does not necessarily indicate that a person is clinically depressed. There are many factors in geriatric populations that will elevate scores on depression measures including anxiety, general psychiatric distress, or physical symptoms related to medical illness. This is particularly true of scores in the lower clinical and subclinical ranges. Another problem with self-report is inherent reporter biases. Many older men may also underreport on depression inventories because of fear of revealing weakness (Eisdorfer et al., 2003). In published papers, one often reports decreased scores of several points on depression inventories as indicating reduced “depression.” What is forgotten is that self-report measures are generally indices of reported depression or psychological distress. Just because a measure is called a depression or anxiety inventory does not imply that it is always capturing clinical depression or anxiety. There are many factors that may account for increases and decreases in these measures, which may have to do with other psychological processes other than clinical depression or clinical anxiety. Therefore, it is always prudent to report self or informant-based measures of depression and anxiety for what they are, self and proxy reports. Overall, it is important to understand the characteristics of a measure and its strengths and limitations.