Leg length discrepancy

Petrone MR, Guinn J, Reddin A, Sutlive TG, Flynn TW, Garber WP. 
The Accuracy of the Palpation Meter (PALM) for Measuring Pelvic Crest Height Difference and Leg Length Discrepancy. 
Journal of Orthopedic & Sports Physical Therapy. 2003; 33/6: 319-325. 

“The validity estimates of the PALM for pelvic crest height difference were excellent (0.90-0.92) when compared with standing AP radiograph of the pelvis.”
Validity (comparison with x-ray): 

excellent : 0,91(average)
Intratester-Reliability: excellent: : 0,97
Intertester-Reliability: very good: 0,88