Inter-rater reliability of postural observation after stroke

Objective: To explore the inter-observer reliability of bedside observation s of stroke patients' posture using two versions of a pictorial tool. Design: Three projects were conducted. The initial version of the tool was used in project 1. The modified version was used in projects 2 and 3. In ea ch project a pair of observers (comprising the main observer and one of fiv e co-observers with varying degrees of experience in observing posture) use d the tool to make simultaneous observations of 19 aspects of the posture o f a sample of stroke patients. Each patient was observed in one or more of four positions (seated, supine and lying on the affected and unaffected sid e). The degree of inter-observer agreement was sought by calculating kappa values and percentage agreement. Setting. Medical wards, care of the elderly wards and a stroke unit. Subjects: A convenience sample of 57 stroke patients. Results: Four hundred and forty paired sets of observations were made (200 in project 1, 140 in project 2 and 100 in project 3). The main observer was in every pair. The co-observers made between 50 and 135 sets of observatio ns each. When the results from all three projects were amassed, acceptable percentage agreement (i.e. greater than or equal to 70%) was obtained for 6 7% (n = 78) and 73% (n = 55) of the results collected on aspects of the pos ture of the affected upper and lower limbs respectively. In contrast, accep table percentage agreement for observations relating to the head, neck and trunk was obtained for only 34% (n = 50) of the results collected. Uneven d istributions in the data made kappa values difficult to interpret. inter-ob server agreement was not noticeably higher for pairs in which both observer s had prior experience of observing posture after stroke than for pairs in which one observer was relatively inexperienced. Conclusions: The tool has potential as a quick and simple means of collecti ng information at the bedside about stroke patients' posture. Refinements, additional training in using the tool for observers and further testing are suggested before its wider use is advocated.