African Americans were less likely to have a depression diagnosis recorded than were non-African Americans during visits to primary care physicians, even after controlling for mood disorder related symptoms. Primary care physicians possibly perceive African American patients to be stigmatized by a depression diagnosis more frequently than non-African American patients and thus choose not to assign them this diagnosis. It is also conceivable that primary care physicians do not assess physical and mood symptoms in African American patients as indicative of depression because of preconceptions about African American patients and their morbidities. The causes of racial differences in diagnosis rates cannot be determined from the NAMCS data set and warrant further study with different research strategies.
The duration of the visit had a significant effect on the probability that a depression diagnosis was recorded. Given that primary care physicians typically treat or monitor several conditions during a relatively short visit, it is not surprising that depression is recognized and diagnosed more often during longer visits. However, it may not be the case that depression was recognized because the visit was longer. It may be that visits of depressed patients just take longer. It is not possible to determine the causal relationship with this data. Again, further studies are needed of the physician diagnosis-making process.
Finally, a depression diagnosis was much more likely to be recorded during visits to family practice or general practice physicians than to internists. One may speculate that this occurs because the training of family/general practice physicians focuses more extensively on the identification and treatment of psychosocial problems than does the training of physicians who specialize in internal medicine. Only a third of training directors for internal medicine residencies were satisfied with the training received by their residents with regard to depression.24 Additionally, internists are much less likely to consider themselves responsible for treatment of depression than are family physicians.10 Although it is possible that the prevalence of depression is greater among patients treated by family/general practice physicians than internists, differences in the true prevalence of depression among physician practices could not be ascertained using this data. However, controlling for patient symptoms should have accounted for much of the difference in prevalence.
Limitations
The study’s findings should be interpreted cautiously because of various limitations of the dataset. This analysis was based on a nationally representative sample of physician office visits in which a diagnosis of depression was recorded. The use of diagnoses that primary care physicians coded sets a threshold that is not equivalent to recognition that might be assessed by direct inquiry of the physicians. Also, since the NAMCS only allows for the recording of 3 diagnoses, the physician conceivably recognized depression but did not record it because a higher priority was assigned to 3 other diagnoses. This quite conceivably is occurring with regard to visits by elderly patients who frequently experience multiple conditions. However, over 80% of visits by all subjects only had 1 or 2 diagnoses recorded during the visit, suggesting that in most cases, a depression diagnosis was not “crowded out.” Additionally, a sensitivity analysis conducted only on visits where 2 or fewer diagnoses were recorded during the visit found the same factors associated with a recorded depression diagnosis. The NAMCS data also only allows for the recording of 3 patient reasons for the visit. If a patient had more than 3 reasons for the visit, only the top 3, as identified by the physician, were recorded in the survey. This could lead to important patient symptoms being excluded from the survey. Thus, the analysis could not perfectly control for all the patients’ reasons for the visit, and this limitation should be kept in mind when interpreting these findings. Another limitation of the data is that no assessment of history of depression that might be an important clue for primary care physicians is recorded in the NAMCS survey.
Conclusions
There are many factors associated with physician recording of a depression diagnosis beyond the patient’s reported symptoms. Therefore, if rates of diagnosis of depression in office-based practice are to more closely approximate the true prevalence of the disorder, interventions are needed that go beyond simply helping physicians to better recognize the symptoms of depression. A recent review found that approximately one fourth of interventions designed to increase recognition and management of depression had no effect on diagnosis and treatment rates.6 Perhaps their effectiveness could be improved by designing more focused interventions that target African American and elderly patients who presently are assigned low rates of depressive diagnoses in primary care. This is a particularly high priority, since both African American and elderly patients are more likely to seek treatment in the primary care sector rather than the mental health specialty sector. Solberg and colleagues25 found that primary care physicians viewed systematic screening unfavorably, but were supportive of alternative approaches, such as external feedback about the care that they provide. Thus, feedback about differences in age-and race-specific rates could possibly provide the impetus needed for primary care physicians to alter their assessment procedures and clinical formulations in these under-recognized groups of patients. Finally, intervention efforts may want to focus on the unique manner in which internists formulate psychiatric diagnoses, since recognition rates for depression are unduly low in this specialty group.