Signs and Evidence

Making clinical sense of scientific data


Carpal tunnel syndrome

Calculated pretest-probability: 4.9 %
Relevant inclusion criteria: Working population Calculate probabilities!

Clinical signs

Closed fist sign
 Positive likelihood ratio
7.30 ( Christopher A et al. )
(average) 7.30
Negative likelihood ratio
0.40 ( Christopher A et al. )
(average) 0.4
Hypalgesia in median nerve territory
 Positive likelihood ratio
3.10 ( Christopher A et al. )
3.40 ( Kuhlman K et al. )
(average) 3.25
Negative likelihood ratio
0.70 ( Christopher A et al. )
0.58 ( Kuhlman K et al. )
(average) 0.64
Nocturnal paresthesia
 Positive likelihood ratio
1.60 ( Christopher A et al. )
(average) 1.60
Negative likelihood ratio
0.70 ( Christopher A et al. )
(average) 0.7

Further signs

Electrodiagnostic testing (EDX)
 Positive likelihood ratio
3.64 ( Fowler JR et al. )
2.59 ( Atroshi I et al. )
(average) 3.12
Negative likelihood ratio
0.26 ( Fowler JR et al. )
0.41 ( Atroshi I et al. )
(average) 0.34

Sources used:

1.Christopher A et al. Does This Patient Have Carpal Tunnel Syndrome? JAMA. 2000;283(23):3110-3117
2.Kuhlman K et al. Sensitivity and specificity of carpal tunnel syndrome signs. American Journal of Physical Medicine & Rehabilitation. 76(6):451-457, nov 1997
3.Fowler JR et al. The Sensitivity and Specificity of Ultrasound for the Diagnosis of Carpal Tunnel Syndrome: A Meta-analysis. Clin Orthop Relat Res. 2011 Apr; 469(4): 1089–1094
4.Atroshi I et al. Diagnostic properties of nerve conduction tests in population-based carpal tunnel syndrome. BMC Musculoskelet Disord. 2003; 4: 9
5.Dale AM et al. Prevalence and incidence of carpal tunnel syndrome in US working populations: pooled analysis of six prospective studies. Scand J Work Environ Health. 2013 Sep 1; 39(5): 495–505
6.Atroshi I et al. Prevalence of carpal tunnel syndrome in a general population. JAMA. 1999;282(2):153–158
7.Khedr et al. Prevalence of Common Types of Compression Neuropathies in Qena Governorate/Egypt: A Population-Based Survey. Neuroepidemiology 2016;46:253-260