More than a third of stroke patients in East Yorkshire waited too long to be admitted to a specialist ward, during the 2017/18 financial year.
In Hull, 31-percent of patients were not admitted to a stroke unit within four hours of arriving at hospital, in the East Riding, it was at 36-percent.
Across England, over 41% of strokes patients weren't admitted within the target time.
The East Riding CCG say they continue to work with the hospital trusts to improve performance.
Meanwhile, the Hull CCG say they've seen improvements over the past two years in the proportion of patients admitted within four hours.