The DI group required fewer needle passes ( median interquartile range : 4 2 vs 7 3 ; P < 0.0001 ) as well as shorter needling ( 8.4 2.9 vs 10.7 2.7 minutes ; P < 0.0001 ) and performance ( 9.0 3.2 vs 11.2 3.0 minutes ; P = 0.001 ) times .