Studies not written in English.

Studies that include participants who are not human.

Studies where the primary focus was not on the care of frail older people, for example, studies only focused on the prefrail population.

Studies which focused on managing a specific condition in frail individuals.

Studies which were letters, notes or conference abstracts only.

Studies where there was no description of any intervention or guidelines.

Studies that did not report any outcome or results.

Studies where there were no primary care elements.

Studies in which further information to make an assessment could not be obtained.

Studies where there was no description or detail on how frail individuals were included in the study.