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Oxford University Hospitals NHS Foundation Trust
Research and Development

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Mental Capacity Act (MCA)

The Mental Capacity Act provides a statutory framework for acting and making decisions on behalf of individuals who lack the capacity to do this for themselves. The Act sets out who can take decisions, in which situations, and how they should go about this.

Research Studies involving adults aged 16 or over who lack capacity must comply with the Mental Capacity Act 2005.

This includes persons with:

  • dementia;
  • learning disabilities;
  • mental health problems;
  • stroke; or
  • head injuries

who may lack capacity to make certain decisions, including consenting to participate in a research study.

The Act does not apply to studies falling under the Clinical Trials Regulations (CTIMPs).

Any research involving a person lacking capacity that would otherwise have required consent from participants may only be lawfully carried out if a REC in England or Wales has given a favourable opinion. This includes research that would otherwise fall outside the remit of an NHS REC.

The REC can only approve the research if it meets the following criteria:

  • the research must relate to the condition causing the mind or brain impairment, or to a condition resulting from or attributed to the mind or brain impairment
  • the research cannot be performed effectively on people who have mental capacity; and
  • the research must produce results relevant to the condition (or a similar condition) affecting the person and have little risk or low adverse impact on the person, or it must have potential benefits to the person without disproportionate risk.

The researcher must stop the research if, at any time, they think that one of the above criteria is not met, unless withdrawal of any treatment as part of the research would impose a significant health risk.