Screening for diabetic retinopathy: a survey of health authorities during a period of transition.
Thompson
J R
JR
Grimshaw
G M
GM
Wilson
A D
AD
Baker
R
R
D003930:Diabetic Retinopathy / Q000175:diagnosis*; D004739:England; D019538:Health Care Surveys; D006291:Health Policy; D006801:Humans; D012042:Registries; D013222:State Medicine / Q000706:statistics & numerical data; D014852:Wales