Inter-rater agreement of observable and elicitable neurological signs

Abstract

This paper reports on a study that aimed to assess the inter-rater agreement of observable neurological signs in the upper and lower limbs (eg inspection, gait, cerebellar tests and coordination) and elicitable signs (eg tone, strength, reflexes and sensation). Thirty patients were examined by two neurology doctors, at least one of whom was a consultant. The doctors' findings were recorded on a standardised pro forma. Inter-rater agreement was assessed using the kappa (κ) statistic, which is chance corrected. There was significantly better agreement between the two doctors for observable than for elicitable signs (mean ± standard deviation [SD] κ, 0.70 ± 0.17 vs 0.41 ± 0.22, p = 0.002). Almost perfect agreement was seen for cerebellar signs and inspection (a combination of speed of movement, muscle bulk, wasting and tremor); substantial agreement for strength, gait and coordination; moderate agreement for tone and reflexes; and only fair agreement for sensation. The inter-rater agreement is therefore better for observable neurological signs than for elicitable signs, which may be explained by the additional skill and cooperation required to elicit rather than just observe clinical signs. These findings have implications for clinical practice, particularly in telemedicine, and highlight the need for standardisation of the neurological examination.

Keywords: Elicitable signs; inter-rater reliability; neurological examination; observable signs; telemedicine.

Fig 1.

Agreement of neurological signs. Note: κ results for chorea, fasciculation and pronator drift are zero, because they were not observed by any of the clinicians.