For what purpose is a clean catch midstream specimen (CCMS) used?

A clean catch midstream specimen (CCMS) is specifically used to obtain a urine sample for testing. This method ensures that the urine collected is as free from contaminants as possible, which is crucial for accurate laboratory analysis. During the process, the individual cleans the genital area to minimize the presence of bacteria and collects urine after urinating a small amount into the toilet. This technique is important in preventing contamination from skin flora or bacteria that might reside in the urethra, providing a more accurate representation of the individual's urinary health.

The other options, while they serve specific medical purposes, do not relate to the collection of urine. Gastric emptying is assessed through different methods, such as imaging or breath tests. Measuring blood pressure involves the use of a sphygmomanometer rather than a urine sample. Evaluating skin conditions requires visual or physical examination of the skin rather than any urine analysis. Therefore, the clean catch midstream specimen is solely and effectively utilized for obtaining urine samples for various tests, making the selected answer accurate.