The Social Security (Medical Evidence) and the Statutory Sick Pay (Medical Evidence) (Amendment) Regulations 2010 come into effect on 6th April. From then on, if you're off sick and your employer asks you to provide written evidence, you'll have to ask your doctor for a 'fit note', also known as a 'statement of fitness for work.'
The regulations allow doctors to issue printed notes/statements rather than handwritten ones. Each statement will list four changes that a doctor can recommend an employer make to an employee's work environment or job role to help facilitate their return to work, namely: (1) "a phased return to work"; (2) "altered hours"; (3) "amended duties"; and (4) "workplace adaptations."
The statement will also have a comments box where doctors can list the functional effects of conditions and other changes the doctor feels an employer should make to facilitate a return to work.
You can see a sample statement of fitness for work and read the Government's response to consultation on the regulations on the Department of Work and Pensions website.
** Additional information & advice **
Alternatively, you may want to speak with an employment law solicitor. You can find a solicitor in your area for free via solicitor matching services, which can also help you to understand the best course of action for your situation and whether you are ready to hire a solicitor.