Prone instability test: Patient lies prone with trunk supported on examining table and feet resting on the floor. The therapist then performs PAIVM to each level of the lumbar spine. Note any provocation of pain during the movement. The PAIVM test is then repeated with the patient’s feet off the floor. Test is positive if pain is recorded in resting position but disappears in the second position. Reported to have low to moderate sensitivity (61%) and specificity (57%), and almost perfect interrater reliability (Fritz et al. 2005).