Table 1. Patient and treatment characteristics of included studies investigating diagnostic accuracy of elements of patient history or physical examination compared with imaging or findings at surgery.^*.

Author	Study design (LoE)	Demographics	Symptoms/patient history	Signs/physical examination	Reference standard; criteria positive CES diagnosis	Study objective; inclusion/exclusion
Balasubramanian et al;1 (2010) Domen et al,3 (2009)	Retrospective diagnostic study	N = 80 Male: NR Mean age: NR (range, 21–90 y) (57% in 4th and 5th decades)	Back pain: 90% (72/80) Unilateral leg pain: 75% (60/80) Bilateral leg pain: 11% (8/80) Bladder incontinence: 48% (33/69) Bladder retention: 18% (14/79) Bowel incontinence: 15% (12/79) Mean duration of symptoms: NR	Saddle sensory deficit/saddle anesthesia: 26% (20/77) Reduced anal tone/ lax anal sphincter: 9% (7/75)	MRI Details of lumbar MRI scans: NR Criteria for CES diagnosis (MRI): Canal compromise > 75%	Objective To evaluate efficacy of clinical assessment in diagnosing CES Inclusion All patients seen by on-call spine surgery team presenting with clinical features of CES (Jan–Dec 2010) Exclusion NR
Bell et al2 (2007); Balasubramanian et al1 (2010)	Prospective diagnostic study	N = 23 Male: 61% Mean age: 39 (range, 17–59) y	Back pain: 100% (23/23) Sciatica: 74% (17/23) Unilateral sciatica: 57% (13/23) Bilateral sciatica: 17% (4/23) Urinary symptoms (any): 100% (23/23) Urinary incontinence: 26% (6/23) Painful urinary retention: 30% (7/23) Painless urinary retention: 4% (1/23) Decreased sensation of urination: 30% (7/23) Frequent urination: 30% (7/23) Erectile dysfunction: 0% males (0/14) Mean duration of back pain: 745 (range, 1–4500) d Mean duration of urinary symptoms: 4 (range, 1–24) d	NR	MRI Details of lumbar MRI scans: NR Criteria for CES diagnosis (MRI): Disc prolapse causing significant cauda equina/ thecal distortion	Objective To determine whether any single symptom can be used to accurately predict presence of CES on subsequent MRI Inclusion All patients referred to one neurosurgical center from primary care with suspected diagnosis of CES Exclusion Patients who admitting neurosurgical registrar was confident did not have signs or symptoms of CES; patients who had already received diagnostic imaging
Domen et al3(2009); Bell et al,2 2007	Retrospective diagnostic study	N = 58 Male: NR Mean age: NR	Low back pain <1 mo: 74% (43/58) Bilateral sciatica: 33% (19/58) Bladder incontinence: 40% (23/58) Bladder retention: 64% (37/58) Decreased sensation of urination: 36% (21/58) Frequent urination: 10% (6/58) Bowel incontinence: 16% (9/58) Mean duration of symptoms: NR	Urinary retention > 500 mL: 21% (8/39 tested) Saddle anesthesia/numbness: 36% (21/58) Decreased anal sphincter tone: 16% (9/58) Decreased anal sphincter reflex: 40% (23/58) Lasègé straight leg test positive: 48% (28/58) Loss of motor function in leg: 50% (29/58) Loss of motor function in foot raisers: 33% (19/58) Decreased ankle reflex: 29% (17/58)	MRI Details of lumbar MRI scans: All scans done on same 1.5-T clinical MRI scanner (Intera; Phillips, Best, the Netherlands) using following sequences (done according to in-house lumbar protocol): sagittal T1-weighted MRI (12 slides; SL 4.00 mm; TR 550 ms; TE 13 ms), sagittal T2-weighted MRI (12 slides; SL 4.0 mm; TR 3191 ms; TE 130 ms), axial driven-equilibrium (T2) MRI (50 slides; SL 2.0 mm; TR 700 ms; TE 1010 ms) and MR cauda equina myelography Criteria for CES diagnosis (MRI): Presence of cauda equina compression	Objective To determine whether the presence or absence of CES can be accurately predicted by certain clinical characteristics in the hopes of avoiding unnecessary urgent MRI scans Inclusion All patients who underwent urgent MRI imaging for suspected CES at hospital neurology department (Jan 2003–Dec 2007) Exclusion Patients with pre-medical history of recent or extensive malignant disease; patients with metastatic disease as cause of CES
Rooney et al4 (2009); Domen et al3 (2009)	Retrospective diagnostic study	N = 98† Male: 27% (18/66)† Mean age: 43 y	Low back pain: 94% (58/62) Sciatica: 89% (49/55) Unilateral sciatica: 60% (33/55) Bilateral sciatica: 29% (16/55) Leg numbness: 83% (33/40) Unilateral leg numbness: 53% (21/40) Bilateral leg numbness: 30% (12/40) Bladder incontinence: 56% (27/48) Bladder retention: 43% (17/40) Decreased sensation of urination: 43% (18/42) Bowel incontinence: 8% (4/48) Bowel retention: 13% (5/40) Decreased fecal sensation: 5% (2/42) Mean duration of symptoms: NR	Saddle numbness: 55% (34/66) Leg numbness: 80% (49/61) Loss of power (unilateral or bilateral): 59% (38/64) Unilateral loss of power: 33% (21/64) Bilateral loss of power: 19% (12/64) Loss of reflexes (unilateral or bilateral): 41% (26/64) Unilateral loss of reflexes: 22% (14/64) Bilateral loss of reflexes: 19% (12/64) Increase in reflexes (unilateral or bilateral): 14% (9/64) Unilateral increase in reflexes: 2% (1/64) Bilateral increase in reflexes: 13% (8/64)	MRI Details of lumbar MRI scans: NR Criteria for CES diagnosis (MRI): Relevant abnormality on scan (details NR)	Objective To assess whether any simple clinical characteristics are able to distinguish patients with CES from those without Inclusion All patients referred to neurosurgical department at hospital with symptoms suggestive enough of CES to warrant MRI (Mar–Dec 2004) Exclusion Readmissions of same patient; previous MRI scan in different hospital; on clinical reevaluation CES seemed unlikely; incomplete records (32 patients had incomplete records)

^*CES indicates cauda equina syndrome; NR, not reported; and MRI, magnetic resonance imaging.

^†Complete records available for 66 of 98 patients, the remaining 22 were excluded; all data reported for n = 66 patients with complete records.