Service reform in the capital must go beyond Healthcare for London proposals and focus on prevention if fatal strokes are to be avoided, the London health observatory has warned.

In a study published today, the observatory says the plans, based on junior health minister Lord Darzi's recommendations, must focus on preventive action, as acute stroke care and rehabilitation services alone will not have as much impact.

Early intervention, public education and smoking cessation could reduce incidence by as much as 80 per cent, it adds.

Observatory director Bobbie Jacobson said: "Healthcare for London offers early prevention as a principle but doesn't choose to illustrate it with evidence.

"We have a problem with getting the basics right in primary care. We don't think beyond the polyclinic model. Polyclinics should be seen as one part of the spectrum."

"Missed opportunities" identified by the observatory include huge variation in GP identification of stroke. In Bromley more than 80 per cent of patients suffering a form of stroke are identified by GPs. In Haringey the figure is just over 60 per cent.

The research also reveals that black Londoners suffer 60 per cent more strokes than white Londoners.