The instrument consists of 19 questions
where:
• Point assignments is discussed on page 1889, first column.
• Some point assignments may need review. For example, pain in the foot or ankle without pain higher up strikes me as unusual to be due to back pain.
• The point assignment for actions that relieve the pain is unclear to me. According to the text, it could be scored as +1 for each activity. But it would seem that the pain is worse if no activity relieves the pain. So I scored it as (4 – (number of actions relieving the pain)).
• Many scores of pain relief distinguish between different types of "painkillers".
total number of points =
= SUM(points for all questions answered)
back pain severity score =
= (SUM(points for all questions answered) / SUM(maximum points for questions answered)) * 100
Interpretation:
• minimum back pain severity scale: 0
• maximum back pain severity scale: 100
• The higher the score, the greater the severity of the back pain.
Performance:
• The authors found the instrument valid and reliable.
• It was compared to the Oswestry, Waddell and Greenough indices.
• It correlated with the SF-36 as a general measure of health status. It was able to detect significant changes in patients and was more responsive than the SF-36.
• It shows good internal consistency and test-retest reliability.
• The instrument shows construct validity.
