Information extracted from the primary studies and coding procedure
| Information extracted | Coding |
| Title of the paper | Full title of the paper |
| First author name | First author’s last name |
| Publication date | Publication date of the paper |
| Language of the paper | Language in which the paper is written |
| Publication on a peer-review journal | “Yes”, “No” |
| Publication type | “Published on a journal”, “Conference paper”, “Thesis/doctoral dissertation” |
| Country where the study was conducted | Name of the country |
| Participants’ inclusion criteria | Quote the inclusion criteria reported in the study paper |
| Participants’ exclusion criteria | Quote the exclusion criteria reported in the study paper |
| Total sample size in the study | Total sample size in the study |
| Participants with lumbar spinal stenosis | No of clinical participants with lumbar spinal stenosis |
| Control participants | No of control participants |
| Matched controls | “Yes”, “No” If Yes, specify if match was made on age or gender or both |
| Age | Total study mean age and SD. If the study does not report these data, they will be requested from the corresponding author. If this is not the case, mean and SD will be estimated from median and IQRs through the formula proposed by Wan and colleagues.57 Otherwise, the study will be excluded from the analyses involving data on age |
| Women | Total percentage of women in the study |
| Married/cohabitant patients | Total percentage of married/cohabitant patients |
| Employed patients | Percentage of employed patients |
| Research design | “Cross-sectional case–control”, “Longitudinal” |
| Lumbar spinal stenosis diagnosis | Diagnostic criteria used to establish diagnosis |
| Instrument(s) used to establish lumbar spinal stenosis diagnosis | Acronym of the instrument(s) |
| Instrument(s) used to assess health-related quality of life | Acronym of the instrument(s) |
| Type of instrument(s) used to assess health-related quality of life | “Clinician-administered interview”, “Self-report questionnaire” |
| Instrument(s) used to evaluate objective functional impairment | Acronym of the instrument(s) |
| Duration of lumbar spinal stenosis | Study mean duration of lumbar spinal stenosis in months |
| Clinical population | “Outpatient”, “Inpatient” |
| Strategies used to recruit clinical participants | Quote the strategies reported in the study paper |
| Strategies used to recruit controls | Quote the strategies reported in the study paper |
| Setting where clinical participants were recruited | Quote the setting where patients were recruited |
| Comorbidity of depressive disorders | Percentage of patients with comorbid depressive disorders in the study according to any version of any international standardised classification systems |
| Instrument(s) used to assess disability related to lumbar spinal stenosis | Acronym of the instrument(s) |
| Disability related to lumbar spinal stenosis | Study mean scores on the Swiss Spinal Stenosis Questionnaire and Oxford Spinal Stenosis Score52 |
| Instrument(s) used to assess self-reported pain severity | Acronym of the instrument(s) |
| Self-reported pain severity | Study mean scores on the Visual Analog Scale for pain, Numeric Rating Scale for pain, McGill Pain Questionnaire53 |