1. LJ Stovner et al. ‘Epidemiology of headache in Europe’. Eur J Neurol. 2006 Apr;13(4):333-45. http://onlinelibrary.wiley.com/doi/10.1111/j.1468-1331.2006.01184.x/full

2. BMJ Best Practice. ‘Migraine headache in adults’. Last updated December 19 2016. Accessed online May 2017. http://bestpractice.bmj.com/best-practice/monograph/10/basics/epidemiology.html

3. International Headache Society, The International Classification of Headache Disorders 3rd edition (Beta version). Accessed online May 2017. https://www.ichd-3.org/

4. NHS Choices. Tension-type headaches. Last reviewed August 7 2015. Accessed online May 2017. http://www.nhs.uk/Conditions/headaches-tension-type/Pages/Introduction.aspx

5. OUCH UK. Organisations for the Understanding of Cluster Headache. Accessed online May 2017. https://ouchuk.org/basics

6. The Migraine Trust. ‘Types of migraine’. Accessed online May 2017. https://www.migrainetrust.org/about-migraine/types-of-migraine/

7. C Gaul et al. ‘Results from a pharmacy-based patient survey on the use of a fixed combination analgesic containing acetylsalicylic acid, paracetamol and caffeine by self-diagnosing and self-treating patients’. SpringerPlus20165:721. Published online June 14 2016. https://springerplus.springeropen.com/articles/10.1186/s40064-016-2369-0

8. NHS. Headache. Accessed online May 2017. https://beta.nhs.uk/symptoms/headache?WT.mc_id=organic_split

9. S Tekki-Rao. Luton & Dunstable University Hospital. ‘Headaches in children & New NICE Guidance’. April 2014. Powerpoint downloaded May 2017 https://www.ldh.nhs.uk/EasySiteWeb/GatewayLink.aspx?alId=10778

10. P Singh. ‘Red flag symptoms: Headaches in children. GP. March 20 2015. Accessed online May 2017. http://www.gponline.com/red-flag-symptoms-headaches-children/neurology/article/1338830

11. NICE CKS Clinical Knowledge Summaries. ‘Migraine’. Last revised May 2016. Accessed online May 2017. https://cks.nice.org.uk/migraine#!topicsummary

12. NICE CKS. ‘Headache - tension type’. Last revised April 2015. Accessed online May 2017. https://cks.nice.org.uk/headache-tension-type#!topicsummary

13. BNF. Section 4.7.4.2 ‘Cluster headache and the trigeminal autonomic cephalalgias’. Accessed online May 2017. https://www.evidence.nhs.uk/formulary/bnf/current/4-central-nervous-system/47-analgesics/474-antimigraine-drugs/4743-cluster-headache-and-the-trigeminal-autonomic-cephalalgias

14. NICE. ‘Transcutaneous stimulation of the cervical branch of the vagus nerve for cluster headache and migraine’. Interventional procedures guidance IPG552. Published March 2016. Accessed online May 2017. https://www.nice.org.uk/guidance/ipg552

15. T Martin. electroCore. NICE provides positive guidance on electroCore’s gammaCore treatment for the prevention and acute treatment of migraine and cluster headache. Posted online April 1 2016. Accessed online May 2017. http://www.electrocore.com/nice-provides-positive-guidance-on-electrocores-gammacore-treatment-for-the-prevention-and-acute-treatment-of-migraine-and-cluster-headache

16. NICE. ‘Transcutaneous electrical stimulation of the supraorbital nerve for treating and preventing migraine’. Interventional procedures guidance IPG559. Published May 2016. Accessed online May 2017. https://www.nice.org.uk/guidance/ipg559

17. Cefaly. Accessed online May 2017. http://www.cefaly.co.uk/en

18. HA Didier et al. ‘Electromyography data in chronic migraine patients by using neurostimulation with the Cefaly device’. Neurological Sciences. May 2015. 36: Supp 1; 115-119. https://link.springer.com/article/10.1007/s10072-015-2154-9

19. D Magis et al. ‘Cerebral metabolism before and after external trigeminal nerve stimulation in episodic migraine’. Cephalgia. Published online June 23 2016. http://journals.sagepub.com/doi/abs/10.1177/0333102416656118

20. S Penning, J Schoenen. ‘A survey on migraine attack treatment with the CEFALY device in regular users’. Acta Neurologica Belgica. June 2017. 117; 2: 547–549. https://link.springer.com/article/10.1007%2Fs13760-017-0757-z