• Consider admission if:
• The person has atrial fibrillation — they are at higher risk for early stroke.
• Refer immediately (the target is to be seen by a specialist and investigated within 24 hours of the start of symptoms) if:
• The person's ABCD2 score is 4 or more — they are at higher risk for early stroke.
• The person has had two or more transient ischaemic attacks (TIAs) within 1 week — they are at higher risk for early stroke.
• The person is on anticoagulation treatment — brain imaging is required to exclude intracranial bleeding.
• Consider immediate referral if:
• The person has recurrent TIAs more than 1 week apart — they are at higher risk for early stroke.
• Refer urgently (the target is to be seen by a specialist and investigated within 1 week of the onset of symptoms) if:
• The person presents sufficiently early and is at lower risk of an early stroke, that is has both:
• An ABCD2 score of 3 or less.
• No other TIAs within the past week.

• The purpose of referral for specialist assessment and imaging of the brain and carotid arteries is to:
• Exclude bleeding (especially in people with symptoms of long duration and in people on anticoagulants).
• Exclude other stroke mimics.
• Confirm the diagnosis and identify the likely causes.
• Identify the vascular territory compromised by the transient ischaemic attack (TIA).
• Identify the appropriate treatment.
• Referral is not needed when the person is already on optimal therapy, a confident diagnosis of TIA can be made, the carotid arteries have been assessed, new atrial fibrillation has been excluded, and the TIA does not involve new vascular territory.
• Arrangements for referral out of hours:
• Follow local arrangements when making a referral out of hours.
• Local stroke services have TIA pathways with different arrangements for meeting the 24-hour target for being assessed. For example, some services have a protocol-driven out of hours service for the emergency department.

These recommendations are in line with guidelines issued by the National Institute for Health and Clinical Excellence (NICE) and the Royal College of Physicians Intercollegiate Stroke Working Party (RCP ICSWP) [Intercollegiate Stroke Working Party, 2008; National Collaborating Centre for Chronic Conditions, 2008], and goals set by the National Stroke Strategy [DH, 2007]:

• National Stroke Strategy goals:
• The National Stroke Strategy goals are for all people with a potential TIA to be assessed and investigated at a specialist clinic — within 24 hours if they are at high risk, or within 1 week if they are not at high risk.
• Applicability of the ABCD² score:
• The NICE and RCP ICSWP guidelines recommend that the imminent risk of stroke be assessed using a validated tool, such as the ABCD² score. The guidelines point out that:
• These scoring systems exclude people who may be at particularly high risk of stroke, such as those with recurrent events and those on anticoagulation who also need urgent evaluation.
• These scoring systems may not be relevant to people who present late.
• Brain imaging:
• All people in whom anticoagulation is being considered after a TIA (or stroke) should have brain imaging because:
• Haemorrhage can present as a TIA and would be aggravated by anticoagulation treatment.
• Brain imaging may show other unsuspected contraindications to anticoagulation.
• When referral is not needed:
• The Quality and Outcomes Framework guidance for General Medical Services (GMS) contract 2008/09 states, 'However, if the patient is already on optimal therapy and has had their carotid arteries assessed, there is no need for further referral' [BMA and NHS Employers, 2008].
• CKS expert reviewers pointed out that the diagnosis of TIA should be certain, and that new atrial fibrillation and involvement of new vascular territory should also be excluded.