A 57-year-old man presents with progressively worsening low back pain, numbness in his right buttock and thigh, and weakness in his right lower limb. His temperature is elevated and he has tenderness in his lower back and decreased sensation in his right foot. The doctor suspects a 20% chance of spinal malignancy. While an MRI has higher sensitivity and specificity for diagnosis, the doctor considers whether to do an ESR or directly order an MRI. Using a 2x2 table method with the sensitivity and specificity of ESR, the doctor calculates that a positive ESR would increase the probability of malignancy from 20% to 37%.