A poor outcome is not by itself negligence
That sentence is the whole difficulty of this subject, and it is worth stating before anything else. Treatment can be carried out competently and still end badly. Complications occur that nobody caused. A claim is not about whether the result was what you hoped for. It is about whether the care fell below the standard required, and whether that failure, rather than the underlying condition, caused the harm.
That is why these claims turn on independent expert evidence to a degree that no other kind of personal injury claim does, and why they take longer to assess before anyone can tell you whether there is anything in them.
What to send us in a first enquiry
A short chronology: when you first attended, who you saw, what was said, what was done, and when things went wrong. The names of the hospital or clinic and of the practitioners. Any records, discharge letters, imaging reports, prescriptions or consent forms you already hold. Whether you have made any complaint, and to whom, and whether anybody has replied.