Healthcare experience is a pretty broad term. In Texas, you may request to be exempt from CNA training and take only the exam, if either of the following applies to you:
You are currently enrolled in a state-accredited school of nursing in any state and have demonstrated competency in providing basic nursing skills in accordance with the school's curriculum. In this case you have to complete Form 5513, “Request to Take the Competency Evaluation Program (CEP) Based on Competency in Basic Nursing Skills” as an RN or LPN student.
After July 1, 1989, you successfully completed the training portion of an approved Nurse Aide Training and Competency Evaluation Program (NATCEP) in any state and have not completed the CEP test or been placed on the registry in another state. In this case you have to complete Form 5510, “Request to Take the Competency Evaluation Program (CEP) Based on Approved Nurse Aide Training Out of State”.
After July 1, 1989, you successfully completed military training of 100 hours or more that is equivalent to a civilian nurse aide training program. In this case you have to complete Form 5511, “Request to Take the Competency Evaluation Program (CEP) Based on Military Training as a Nurse Aide”.
After July 1, 1989, you successfully completed a state-accredited registered nurse (RN) or licensed vocational nurse (LVN) school but were not licensed as an RN or LVN in Texas or have not held a license that's been revoked. In this case you have to complete Form 5512, “Request to Take the Competency Evaluation Program (CEP) Based on Completion of an RN or LVN School”.
I am not aware of any other exemptions from training but you may contact the Texas Nurse Aide Registry at 512-438-2050 if you would like to be certain.