On-site mental health workers delivering psychological therapy and psychosocial interventions to patients in primary care: effects on the professional practice of primary care providers

Most people with mental health problems are treated by their family physician or general practitioner. Physicians will treat these problems, often without referral to mental health specialists, and at times the care is not consistent and could be improved.

This review investigated whether having mental health workers on-site to work with physicians at their offices would change the care that physicians provide. Forty-two studies were reviewed in which on-site mental health workers, such as counsellors or psychiatrists, worked alongside physicians to provide therapy to patients. The review found that when there were mental health workers on-site, patients may reduce the number of visits to their doctors; doctors may reduce how often they refer patients to off-site mental health specialists; doctors may reduce the number of drugs they prescribe to the patients who see the mental health workers; and the costs related to those drugs may be lower. However, these reductions were small and not found consistently in all the studies.

The review also found that there may be little or no difference in how the doctors prescribe drugs or refer patients who have mental health problems but are not seeing the on-site mental health workers. It is also not known what the effect of on-site mental health workers had on how well physicians recognised and diagnosed mental health problems.

Authors' conclusions: 

This review provides some evidence that MHWs working in primary care to deliver psychological therapy and psychosocial interventions cause a significant reduction in PCP behaviours such as consultations, prescribing, and referrals to specialist care. However, the changes are modest in magnitude, inconsistent, do not generalise to the wider patient population, and their clinical or economic significance is unclear.

Read the full abstract...

Mental health problems are common in primary care and mental health workers (MHWs) are increasingly working in this setting delivering psychological therapy and psychosocial interventions to patients. In addition to treating patients directly, the introduction of on-site MHWs represents an organisational change that may lead to changes in the clinical behaviour of primary care providers (PCPs).


To assess the effects of on-site MHWs delivering psychological therapy and psychosocial interventions in primary care on the clinical behaviour of primary care providers (PCPs).

Search strategy: 

The following sources were searched in 1998: the Cochrane Effective Practice and Organisation of Care Group Specialised Register, the Cochrane Controlled Trials Register, MEDLINE, EMBASE, PsycINFO, CounselLit, NPCRDC skill-mix in primary care bibliography, and reference lists of articles. Additional searches were conducted in February 2007 using the following sources: MEDLINE, EMBASE, PsycINFO, CINAHL, and Cochrane Central Register of Clinical Trials (CENTRAL) (The Cochrane Library).

Selection criteria: 

Randomised trials, controlled before and after studies, and interrupted time series analyses of MHWs working alongside PCPs in primary care settings. The outcomes included objective measures of PCP behaviours such as consultation rates, prescribing, and referral.

Data collection and analysis: 

Two review authors independently extracted data and assessed study quality.

Main results: 

Forty-two studies were included in the review. There was evidence that MHWs caused significant reductions in PCP consultations (standardised mean difference -0.17, 95% CI -0.30 to -0.05), psychotropic prescribing (relative risk 0.67, 95% CI 0.56 to 0.79), prescribing costs (standardised mean difference -0.22, 95% CI -0.38 to -0.07), and rates of mental health referral (relative risk 0.13, 95% CI 0.09 to 0.20) for the patients they were seeing. In controlled before and after studies, the addition of MHWs to a practice did not affect prescribing behaviour towards the wider practice population and there was no consistent pattern to the impact on referrals in the wider patient population.