Table 1 Inclusion criteria based on PICO framework

1. Study participants were diagnosed with a mental health condition, with primary care being the main source of referral.

2. Mental health was the primary reason for referral.

3. Studies evaluating ERS, as defined by Pavey et al. [21]

o Referral by a primary-care health-care professional to a service designed to increase physical activity or exercise

o Physical activity/exercise programme tailored to individual needs

o Initial assessment and monitoring throughout the programme

4. Studies with any relevant comparator were permitted.

5. Studies had to measure one or more of the following

o Changes in clinical symptoms of mental health conditions (e.g. depression and anxiety) found or managed in primary care

o ERS uptake/adherence rates of individuals referred from primary care for mental health reasons

o Impact of ERS on long-term physical activity levels in participants referred from primary care for mental health reasons.