In evaluating the proportion of the encounter devoted to broad questions (ISIE-81 codes 11, 12, 31, 32), we found the composite medians to be identical at 10.2% between those that did and did not recognize depression. The mean for encounters where depression was recognized was 10.5% (standard deviation [SD] = 4.0%) and was 11.3% (SD = 5.1%) in those who did not recognize depression (P = .552). The calculated measure on the ratio of broad to narrow medical and psychosocial questioning (DM1) was 79% in those who recognized depression and 82% in those who did not (P = .453). All physicians asked broad to narrow questions in a ratio of approximately 4 to 1.
On the basis of the single ISIE-81 code that indicates physicians were asking about or commenting on patient feelings (code 11), we found that physicians who recognized depression asked twice as many questions about feelings on average as those who did not recognize depression (1.9% of total physician activity vs 0.9%, P = .017). Using the composite measure of affective focus (DM2), we found physicians who recognized depression spent 2.7% of their time on the composite affective focus compared with 1.3% for physicians who did not recognize depression, a ratio of about 2 to 1 (P = .003). No instances of physicians interrupting patients to redirect the encounters occurred (ISIE-81 code 16).
On the basis of the physician debriefing telephone calls, we learned that in 60% of encounters depression was recognized immediately; in 26% depression was recognized in the middle of the first interview; and in 4% depression was recognized at the end of the first interview. Ten percent of physicians could not specifically remember when depression was recognized. In evaluating the timing or sequencing of questioning as they relate to a diagnosis of depression, we had initially hypothesized that successful recognizers would show a different pattern. However, no sequence differences related to broad to narrow questions were found between doctors who did and did not recognize depression. All physicians asked many more broad medical questions than psychosocial questions, as illustrated in Figure 1, but that difference was very marked in the first quartile and decreased as the visit went on. The interaction between quartile and medical versus psychosocial questioning was highly significant using multivariate analysis of variance (F [3,55] = 67.54; P <.001). No statistical differences existed between recognizing depression and interview quartile.
Figure 2 shows the timing of questions about patients’ feelings (ISIE code 11) as a function of whether depression was recognized and the point in the visit when depression was recognized. Physicians who successfully recognized depression later in the interview showed an increase in questions about feelings in the quartile just before recognition occurred. It appears that some physicians initiated a series of questions about affect and feelings once they suspected a patient might have minor depression. Physicians who did not recognize depression spent the least amount of time asking affective questions.
Discussion
We found a high proportion (73%) of primary care physicians recognized minor depression, and when this occurred, physician self-reports indicated that it typically happened at the beginning of the encounter (60%). However, we cannot validate the physicians’ self-reports. (Though the standardized patients reported whether depression was recognized, they could not determine when in the encounter it occurred.) We found no differences in the use of broad to narrow questioning between those who successfully recognized depression and those who did not. We did find that the use of affective questioning was associated with successful recognition.
We found differences in the use of affective questioning and the timing of that questioning between those who successfully recognized depression and those who did not. Physicians who reported recognizing depression early in the encounter increased their use of affective questions as the interview progressed. This is likely because they need affective information as they consider treatment options. The curve for physicians who recognized depression in the middle of the encounter shows a marked increase of questions about feelings in the second quartile. Physicians who recognized depression late show an increase in questions about feelings in the third quartile. We did not have the appropriate design or the appropriate data to firmly attribute causality, but if questions about affect were an important contributor to a diagnosis of depression, they would be expected to closely precede the successful diagnosis. Our data are consistent with questions about affect playing an important role in the diagnosis.
Our results agree in some ways and not in others with those of Badger and colleagues,29 who found that 3 communication behaviors predicted with 60% accuracy when physicians would recognize depression and 74% accuracy when physicians would not. These included the proportion of the interview devoted to affective interview behaviors (accepts and elicits feelings, shows approval, reassures, and discloses own feelings), use of broad open-ended psychosocial questions by the physician, and when the physician did the majority of the talking. Though we found use of affective questions was associated with a diagnosis of depression, we did not find support for their finding of the use of broad to focused psychosocial questioning. We found that the majority of questions asked by physicians were broad medical questions, which likely indicates their pursuit of the patient’s presenting complaints of headache.