Privacy notice

Sithi is a trading name of Neurithmetic Ltd (registered in England & Wales no. 15177502), The Courtyard, Shoreham Road, Upper Beeding, Steyning, West Sussex, BN44 3TN. Neurithmetic Ltd is the controller of any personal data described in this notice.

This website

This site does not use cookies, analytics, advertising or tracking tools. If you take the household survey, a random code is kept in your browser's local storage so the survey can recognise your household next week; it is not used for anything else. Our web server keeps standard access logs (IP address, time, page requested and browser type) for up to 30 days for security purposes. We rely on our legitimate interest in operating a secure website.

The weekly update

If you sign up for the weekly update we store your email address, the time you signed up and the time you confirmed. We send one email asking you to confirm; if you do not confirm within seven days the request is deleted. We rely on your consent and use your address only to send the update. Every email includes a link to unsubscribe, which deletes your address straight away. The list is kept on our own server and is not shared or sold. Emails are sent through our email host, Hostinger. We do not use tracking pixels or link tracking.

Correspondence

If you write to hello@sithi.net we use your name, email address and message to reply to you and to keep a record of the correspondence. We rely on our legitimate interest in responding to enquiries. Enquiries are kept for up to two years unless they lead to a contract. We do not sell or share them.

The Sithi household survey

If you take part in the Sithi household survey we collect information about symptoms in your household, which is health information. It is collected only with your explicit consent, kept to a minimum and never linked to your name. The survey privacy notice explains what we collect, how long we keep it and your rights. Neurithmetic Ltd is registered with the Information Commissioner's Office, registration number ZC180071.

Other health data

Apart from the survey, Sithi uses only published, aggregated public statistics.

Your rights

You may ask to see, correct or delete your personal data by writing to hello@sithi.net. You may also object to how we use it or withdraw your consent at any time. If you are not satisfied with our response you may complain to the Information Commissioner’s Office (ico.org.uk).

Last updated 24 October 2026.