His grandfather who remained in Czechoslovakia died shortly afterwards but his grandmother was deported to Theresienstadt (Terezín) concentration camp where she perished.
He served in the Royal Air Force, attached to the Epidemiological Research Laboratory at Colindale, North London and, after a further appointment as Lecturer to the Department of Medicine at St Thomas's, he was made MRC Clinical Research Fellow in the Department of Epidemiology and Medical Statistics at the London School of Hygiene and Tropical Medicine.
This was followed by a year in the Department of Epidemiology at Johns Hopkins School of Hygiene and then his return to St Thomas's in 1962 and his appointment to Professor in 1968.
[7][8] He established strong links with fellow public health researchers in the United States, Australia and Japan.
His groundbreaking paper on validation of medical screening procedures, published jointly with fellow epidemiologist Archie Cochrane in 1971, became a classic in the field.