New health care data from the Patrick administration confirms that some Massachusetts hospitals are paid significantly more than others for providing similar care, but it shows that these differences are even more dramatic for certain common procedures like caesarean births. Cambridge Health Alliance was paid less than $5,000 each for 55 caesarean sections performed in 2009, while Massachusetts General Hospital was paid more than $10,000 each for 483 caesarean deliveries that year, state officials found. They said it was unclear why insurers paid some hospitals dramatically more, since officials found no obvious differences in quality of care, and their analysis allowed for instances in which hospitals treat sicker patients.