Although a cervical swab provides the most sensitive and specific test result for chlamydia, a urine chlamydia also has high specificity and is a good alternative if you’re unable to perform cervical swabs. The sensitivity of the cervical swab is 89-98% compared to 74-88% for the urine test, while the specificity of the tests is 95-98% for the swabs and 96-98% for the urine test.