However, there is good evidence that MHFA training raises awareness of mental ill health conditions for those who have done the course.
The review, which was published in August, examined 29 studies published between January 2000 and July 2017.
The researchers noted that there were few well-designed studies, which may explain the paucity of evidence.
However, the results chime with preliminary findings from research carried out by the Institution of Occupational Safety and Health, the professional body for health and safety managers.
It found that while MHFA helped create a culture where mental health could be discussed, it failed to address the work factors that cause mental ill health, according to Health and Safety at Work magazine.
The HSE report said that people who are MHFA trained have a better understanding of where to find information and professional support and are more confident helping individuals experiencing mental ill health or a crisis.
However, there is no evidence that introducing MHFA training in workplaces has resulted in sustained actions by those receiving the training or that it has improved employers’ management of mental health.
The HSE also analysed whether UK-based MHFA training providers modify their courses to suit workplaces, concluding that there is only limited evidence that they do.
Researchers carrying out the rapid scoping review struggled to find published studies that evaluate the effectiveness of MHFA. The studies that have been conducted tended to be poor quality.
More employers have been training staff in MHFA in recent years. The course seeks to equip employees with the knowledge to respond to people experiencing a crisis or mental ill health. Trainees are taught how to recognise symptoms and risk factors in a range of conditions and signpost people to sources of help, information and additional professional support.
Thriving at Work, the independent review of workplace mental health released in October last year, called on the HSE to expand the advice it offers employers to cover all mental ill health in the work environment, not just work-related conditions.