Patient assessment: validation of a nursing instrument

The aim of this study is to evaluate the reliability and validity of the Byron Physical Assessment Framework (BPAF). The BPAF is a systems based checklist of physiological measurements, signs, and symptoms designed to structure and document the assessment of a patients physical condition by nursing staff. Initially the BPAF was refined using extensive literature review and expert opinion to improve the comprehensiveness and clarity for its intended purpose. As a result the content validity of the BPAF was supported. Inter-rater reliability between both expert-expert and novice-expert pairings was assessed. A total of 68 assessments were conducted by pairs of qualified nurses with patients on general medical and surgical wards and a nursing-led unit in one London Hospital. Reliability of the dichotomous data items of the BPAF was found to be generally good (kappa > 0.6) with only one item showing a poor reliability (kappa < 0.20). Reliability for continuous items such as pulse and respiratory rate was surprisingly low with evidence of large variation between raters in addition to systematic bias. With relatively little teaching, novice assessors were able to use the BPAF and achieve good inter-rater reliability with expert assessors although this was lower than the reliability of the expert diads. The utilisation of the BPAF to fulfil intended purpose was assessed by examining completed assessments and the outcome in terms of nurses' actions in light of new abnormal findings. Both were found to be fair, showing that the BPAF does affect the actions of nurses although it could be utilised more.