Fall risk assessment : A prospective investigation of nurses' clinical judgement and risk assessment tools in predicting patient falls in an acute care setting

Falls are a significant problem in acute care hospital settings, and can have serious consequences, especially for older patients. Fall prevention has therefore been recognised as an important area for research and intervention. In order to target interventions and use resources effectively, a major strategy of many fall prevention programmes has been the development and/or use of risk assessment tools to identify patients who are at high risk of falling. Although many tools have been developed, few have been rigorously tested, and there is currently no evidence to support the clinical utility of fall risk assessment tools. There is a need to conduct further research to establish the efficacy of fall risk assessment tools for inpatient populations. Additionally, nurses' clinical judgement in assessing fall risk may aid the development of fall risk assessment protocols and further research is needed to build on limited knowledge in this area. A prospective cohort study was used to evaluate two fall risk assessment tools and nurses' clinical judgement in predicting patient falls. Each patient was assessed for fall risk by the clinical judgement of the nurse caring for the patient and by the researcher using a data collection form containing the two fall risk assessment tools. The study wards comprised two aged care and rehabilitation wards within a 570 bed acute care tertiary teaching hospital facility in Western Australia. Test-retest reliability of the two fall risk assessment tools and nurses' clinical judgement was established over a twenty four hour period. The ability of the fall risk assessment tools, and nurses' clinical judgements to discriminate between patients with a high probability of falling and patients with a low probability of falling, was determined by calculating the sensitivity, specificity, positive predictive value and negative predictive value for each method. The reference criterion used for these calculations was whether or not the patient fell within the hospitalisation period in which they were admitted to the study. In addition, the accuracy of each method was determined by calculating the number of times the risk assessment tool or clinical judgement classified the patient into the correct fall risk category, expressed as a percentage. The same reference criterion was used for this calculation. Both the fall risk assessment tools and nurses' clinical judgement had good test-retest reliability. When assessing validity, all three methods of determining fall risk showed good sensitivity, ranging from 88% to 91 %, but poor specificity, ranging from 25% to 26%. This meant that the risk assessment methods classified too many patients who did not fall as at high risk for falling. All methods also had limited accuracy, ranging from 35% to 36%, and overall exhibited an inability to adequately discriminate between patient populations at risk of falling and those not at risk of falling. Consequently, neither nurses' clinical judgement nor the fall risk assessment tools could be recommended for assessing fall risk in the clinical setting. In addition, results indicated that there was a large difference between the accuracy of first year enrolled and registered nurses in assessing patient fall risk. First year enrolled nurses accurately predicted fall risk 44.4% of the time while first year registered nurses achieved an accuracy level of only 8.6%. These results are potentially biased, as measuring differences in accuracy between types of nurses was not a main focus of this study and in many cases the same nurse gave multiple judgements about patients' fall risk. The results however, provide an indication that further study is warranted using a specifically designed methodology to explore this issue. There are a number of specific recommendations arising from the results of this study. It is recommended that further studies be undertaken to assess the reliability and validity of current fall risk assessment tools in inpatient populations. If no valid and reliable fall risk assessment tool can be identified, research should be undertaken to develop such a tool. It is also recommended that studies be conducted to assess changes in fall risk profiles over time to determine if the sensitivity and specificity of instruments changes depending on the timing of the risk assessment. Differentiating between stable and transient risk factors should be an integral component of these types of studies. Further research is also required to determine if there are differences in fall risk factors between different specialties or if a generic risk assessment tool can be used for all inpatient populations. Additionally, further investigation into the clinical judgement of registered and enrolled nurses in their first year of clinical practice should be undertaken and results reported to appropriate educational institutions. Changes in accuracy of clinical judgement in the first five years of clinical practice should also be measured.