CRP and Sacroiliac arthritis: N = 155 patients. Clinical evaluation using BASDAI to measure ESR, CRP, planar 99mTc-Methylene scintigraphy, SPECT/CT, and MRI of the pelvic region. On planar bone scintigraphy and SPECT, a score of 0, 1, or 2 was assigned if tracer uptake in SIJ was noted; a score of 2 was considered positive for sacroiliitis diagnosis