Background: Diagnostic support tools for lumbar spinal stenosis such as the Self-administered, Self-reported History Questionnaire have been developed in Japan, but no report has demonstrated the diagnostic accuracy of this questionnaire in Japanese primary care settings. This multicenter, cross-sectional survey was performed to evaluate and improve the diagnostic accuracy of this questionnaire for lumbar spinal stenosis patients in Japanese primary care settings.
Methods: The lumbar spinal stenosis diagnosis support tool project was conducted in 1657 hospitals to evaluate the diagnostic accuracy of the Self-administered, Self-reported History Questionnaire in Japan from 2011 to 2012. Consecutive adults (≥50 years old) from physicians, including non-orthopedic general practitioners and orthopedic general practitioners, were considered for enrollment. Consecutive adults (≥50 years old) with low back pain from hospital-based orthopedic surgeons were also considered for enrollment. The diagnostic accuracy of the Self-administered, Self-reported History Questionnaire with initial and several new cutoff points in classifying patients according to the presence of lumbar spinal stenosis was assessed in terms of sensitivity, specificity and negative predictive values.
Results: Among the 33,545 patients, 10,199 (30.4 %) were diagnosed with lumbar spinal stenosis by the physicians. The Self-administered, Self-reported History Questionnaire version 1.1 with a new cutoff point was more sensitive than the Self-administered, Self-reported History Questionnaire version 1.0 with the initial cutoff point (79.8 vs. 68.3 %) and less specific (68.8 vs. 75.1 %) for lumbar spinal stenosis diagnosis. The respective negative predictive values were 88.5 and 84.3 %.
Conclusions: The Self-administered, Self-reported History Questionnaire version 1.1 with the new cutoff was more sensitive and had higher negative predictive value than version 1.0 with the initial cutoff. Therefore, the improved Self-administered, Self-reported History Questionnaire version 1.1 can be used for lumbar spinal stenosis screening, and its use may improve the quality of lumbar spinal stenosis diagnostic practice in Japanese primary care settings.