Execution:
- Patient is standing upright and barefoot
- The examiner draws a line between the two posterior superior iliac spines
- A second point is marked centrally and 15cm above the line between the two PSIS
- The patient is asked to bend forwards as far as possible whilst keeping the knees fully extended
Positive Outcome: The distance between the lines is the amount of lumbar flexion.
| Study | Reliability | Sn | Sp | LR+ | LR- |
| Rezvani et al. (2012) | Inter-rater ICC=0.97 | NA | NA | NA | NA |
| Comment: Despite finding excellent intrarater reliability r of 0.97 the correlation of the test with radiological measurement was only moderate with a r coefficient of 0.67 | |||||
