MedifocusHealth

Information from a team of rheumatologists, physical therapists, and ankylosing spondylitis (AS) research specialists formed the basis on which a system of tests was created to measure various aspects of disease activity. Known as the Bath Indices, the tests that are used to measure disease activity in ankylosing spondylitis include:

• BATH AS Metrology Index (BASMI)
• BATH AS Functional Index (BASFI)
• BATH AS Disease Activity Index (BASDAI)
• BATH AS Patient Global Score (BAS-G)

BATH AS Metrology Index (BASMI)

This test measures clinically significant changes in spinal movement and consists of measuring the status of cervical, dorsal, and lumbar spine, hips, and pelvic soft tissue. A high score indicates more severe limitation of movement due to ankylosing spondylitis.

BATH AS Functional Index (BASFI)

This test determines the degree of functional limitation of the patient with ankylosing spondylitis. It consists of 10 questions about coping with activities of daily living. Responses are made in conjunction with a visual analog scale which provides the patient with a broader range of possible responses and thus offers a more accurate representation of functional status. Another advantage of the visual analog scale is that it reflects a greater sensitivity to change of status with subsequent testing.

The Dougados Functional Index (DFI) is another score used to evaluate functional capacity of patients with ankylosing spondylitis. The BASFI may be more precise in its discriminative capacity and also examines a wider range of parameters than the DFI.

BATH AS Disease Activity Index (BASDAI)

This test is also administered in conjunction with a visual analog scale and measures responses relating to:

• Fatigue
• Spinal pain
• Joint pain and swelling
• Areas of localized tenderness
• Morning stiffness

The BASDAI is also sensitive to changes that may occur with subsequent testing.

BATH AS Patient Global Score (BAS-G)

This test attempts to enable the health care provider to objectively measure how the patient evaluates their own well being over the past week and the past six months. It is not meant to be administered as a stand alone test, but rather is evaluated in context with the scores from other BATH indices. Scores are measured from 1-10 with the higher numbers indicating a greater degree of AS involvement in everyday life. The BATH indices can be given to all ages, are user friendly, and can be completed quickly.