SQSTM1 and inclusion body myositis: In particular, both LC3 and p62 were sensitive markers of IBM, but the tradeoff between sensitivity and specificity was smaller for LC3 (100% specificity and 83% sensitivity for IBM using a threshold value of 13.4%FS) than for p62 (100% specificity and 50% sensitivity for IBM using a threshold value of 19.6%FS).