The plantar reflex -study of observer agreement, sensitivity, and observer bias

The utility of the plantar reflex in modern neurology is
controversial. We studied the Babinski, Chaddock, and
Oppenheim reflexes in terms of intraobserver, interobserver,
and intertest agreement; sensitivity; positive predictive
value (PPV); and observer bias. Sixty-two
patients and 1,984 reflexes were analyzed. Intraobserver
and interobserver agreement were weak (median
k ,0.4). Intertest agreement was weak (median k ,
0.4) for all paired reflexes, although highest for the
Babinski/Chaddock (0.30) (p , 0.05). There was no
evidence of observer bias. Sensitivity was 59.7% for
the Babinski, 55.3% for the Chaddock, and 30.0% for
the Oppenheim. PPV was 70.3% for the Babinski,
66.5% for the Chaddock, and 61.3% for the Oppenheim.
Our results show consistently low observer
agreement for the plantar reflex. The Babinski and the Chaddock demonstrated comparable
sensitivity and PPV.