Skip to main content

Advertisement

Table 3 Estimated item parameters for a subsample (n = 28) of Read stroke codes retained for the IRT analyses.

From: Potential application of item-response theory to interpretation of medical codes in electronic patient records

Stroke code Discrimination SE Location SE χ2
Thrombosis cavernous sinus 2.785 0.772 4.468 0.490 2136.3
Thrombosis transverse sinus 2.632 0.677 4.677 0.529 1934.8
Thrombosis of CNS venous sinuses NOS 2.077 0.635 5.717 1.007 816.9
CI due to cerebral venous thrombosis, nonpyogenic 1.642 0.446 5.998 1.162 653.7
Cortical haemorrhage 1.824 0.635 6.079 1.279 607.5
Phlebitis and thrombophlebitis of intracranial sinuses 1.813 0.648 6.265 1.458 518.2
Thrombosis lateral sinus 1.732 0.594 6.307 1.478 507.4
Vertebral artery occlusion 1.097 0.522 8.490 3.500 44.7
Subarachnoid haemorrhage from anterior 1.054 0.511 8.793 3.737 34.5
Brainstem infarction NOS 1.051 0.509 8.816 3.754 33.2
CI due to embolism of precerebral arteries 0.905 0.413 8.956 3.677 29.4
Pure motor lacunar syndrome 0.883 0.401 9.059 3.720 10.7
Ruptured berry aneurysm 0.797 0.341 9.177 3.595 7.7
Brainstem infarction 0.783 0.334 9.242 3.613 7.0
Thrombophlebitis of CNS venous sinuses 0.836 0.387 10.002 4.269 4.1
Extradural haemorrhage - nontraumatic 0.843 0.392 10.006 4.283 4.1
Subacute confusional state of cerebrovascular origin 0.811 0.371 10.007 4.227 3.9
Subarachnoid haemorrhage NOS 0.805 0.367 10.012 4.219 3.8
Left sided intracerebral haemorrhage, unspecified 0.850 0.396 10.013 4.299 4.1
Pontine haemorrhage 0.794 0.360 10.024 4.205 3.7
Intracerebral haemorrhage, intraventricular 0.774 0.347 10.059 4.185 3.4
CI due to unspecified occlus of precerbral arteries 0.880 0.417 10.079 4.387 4.0
Infarction of basal ganglia 0.760 0.339 10.091 4.174 3.2
Pure sensory lacunar syndrome 0.897 0.429 10.153 4.456 3.8
Subarachnoid haemorrhage from middle artery 0.735 0.323 10.163 4.161 2.8
Sequelae of stroke not specified 0.706 0.305 10.266 4.154 2.3
Occlusion and stenosis of middle cerebral artery 0.948 0.465 10.696 4.835 5.7
Occlusion and stenosis of posterior cerebral artery 0.972 0.483 11.582 5.384 0.0