Getting down to cases--making mental health interventions effective.

The reports of consultative meetings and expert committees assembled by international organizations necessarily sacrifice bite and specificity for comprehensiveness and diplomatic niceties. The report in question (1) resembles its predecessors and, undoubtedly, its successors in this respect. The points reached by consensus are unexceptionable. But so many points are made, and made so blandly, that they are unlikely to lead to action. What must be added is detailed specification of what needs to be done, what the barriers are to doing it, how those barriers can be overcome, and how progress towards a specified goal can be measured. Let me reflect on the proposal for depression, a disorder that causes an enormous disease burden, one for which cost-effective interventions are available, and one which must be applied in primary care sites, as the Report notes. The extent of the burden from depression has been thoroughly documented by WHO. It is equally clear that there are simply not enough specialized mental health personnel, even in the most affluent countries, to manage all patients suffering from depression. Therefore, public health policy must promote depression management in general health care. However, before expending resources on apparently efficacious treatments, we will need to be certain that they are effective. What is the state of the evidence? This question rests on the distinction between "efficacy" and "effectiveness." "Efficacy" refers to a statistically significant treatment benefit demonstrated in a rigorously designed and executed randomized, controlled trial. "Effectiveness" refers to positive clinical outcomes observed when that treatment is applied in the community under ordinary conditions of practice. Whereas there is substantial evidence for the efficacy of a number of drugs and carefully designed psychotherapies in treating depression, data on effectiveness are at best equivocal when those measures are applied in primary care settings (2, 3). This must give us pause. What can account for the difference between efficacy and effectiveness? First, the characteristics of psychiatric research samples differ from those encountered in primary care. In research studies, enrolled patients must meet specified diagnostic criteria; comorbidity usually leads to exclusion. In contrast, in primary health care, patients with chronicity, comorbidity, and sub-threshold diagnoses make up a substantial fraction of general practice. Second, patients who are willing to accept referral to a psychiatric facility (and to agree to enroll in a research trial) may differ in important ways from those who deny depression and refuse referral, a common pattern in primary care. Motivation to comply with treatment will be much higher. Depression presenting as chronic pain or chronic fatigue involves different clinical challenges from depression presenting with feelings of hopelessness or guilt. Third, part of the gap is attributable to sub-optimal practice. In research, substantial time is invested in explaining the protocol, obtaining informed consent and asking subjects to commit themselves to staying the course. These procedures activate the patient as a participant. Investigators are eager to maintain sample size, so they make themselves unusually available to patients (convenient appointments and schedules, easy phone access, educational material, mailed reminders, etc.). In a busy practice, the press of time often leads to omitting explanation and education. Drug prescribing may be homoeopathic; poor patient adherence further reduces blood levels. …