Screening for depression – shaky guidelines and more controversy with real implications for postpartum depression screening

The Canadian Task Force of Preventive Medicine recently released guidelines for screening for depression in primary care.   The current weak evidence does not support screening for either the general population or subpopulations which include postpartum period, family history, recent traumatic life events, chronic health problems and substance use. Canadiantaskforce Depression guidelines

More fundamental is that awareness of potential for depression should be included as integral in clinical evaluations remain supported.   Calls for additional research that actually look at randomized trials are integral to the recommendations. 

The Canadian recommendations are somewhat at variance to other bodies, but most have come to similar conclusions that clinical alertness is appropriate, that the screening is associated with high rates of false positivity, that systems must be in place for subsequent accurate diagnosis, treatment and follow-up.  The full clinical paper is accessible at CMAJ early release May 15 

Such a recommendation will undoubtedly shake the foundations of certain public health institutions that have been co-opted into routine postpartum screening for depression through the use of the Edinburgh tool or Whooley questions.  As with other well thought out recommendations for the Task Forces on preventative care, there will be the push back from those who believe that their practice is justified and should continue to be widely invested in and implemented.

Conversely that actual review takes a very narrow view of the current evidence and rejected most studies for poor quality – hence the overall conclusion of weak evidence.

There are a few lessons in this endeavour.  First, be sure of the evidence before implementing programs which appear to be of inherent good.  Second, before implementing widespread program and investment, find a solid evidence foundation that will stand up to rigorous scrutiny before shifting resources.   On this later point, public health has too often been the victim of well intentioned leaders and bureaucrats wishing to leave a legacy and demonstrate their contribution to the public good – at a very unfortunate cost.