Adding value to the STRATIFY falls risk assessment in acute hospitals

Abstract

Aim: This paper is a report of a study conducted to compare the predictive accuracy for fallers of The Northern Hospital Modified St Thomas's Risk Assessment Tool and St Thomas's Risk Assessment Tool, and to determine the inter-rater agreement of each tool.

Background: Falls risk assessment is a key component of fall prevention. Investigation of clinimetric properties of a tool should be completed before it are used in clinical practice.

Methods: Local falls data were used to inform modification of the St Thomas's Risk Assessment Tool to improve faller prediction. Clinimetric properties of the St Thomas's Risk Assessment Tool and The Northern Hospital Modified St Thomas's Risk Assessment Tool were examined in a prospective cross-sectional study with acute hospital patients. Phase I involved assessment of predictive accuracy using sensitivity, specificity and the Youden Index (J) with 263 patients. Phase II of the evaluation involved assessment of inter-rater agreement using the Kappa statistic (κ) with 52 patients. Data were collected in 2008.

Results: Impaired balance, age 80 years and older and drug and alcohol problems were identified as additional falls risk factors in The Northern Hospital population and added to the St Thomas's Risk Assessment Tool. The Northern Hospital Modified St Thomas's Risk Assessment Tool had higher sensitivity (0·65 vs. 0·35, P = 0·016). The St Thomas's Risk Assessment Tool had higher specificity (0·93 vs. 0·79, P = 0·000). The Northern Hospital Modified St Thomas's Risk Assessment Tool had the greater overall accuracy (J) (0·44 vs. 0·28, P = 0·006). Inter-rater agreement of The Northern Hospital Modified St Thomas's Risk Assessment Tool was fair (κ = 0·34) and low for the St Thomas's Risk Assessment Tool (κ = 0·19).

Conclusion: The Northern Hospital Modified St Thomas's Risk Assessment Tool and St Thomas's Risk Assessment Tool accurately identified patients at risk of falling. The Northern Hospital Modified St Thomas's Risk Assessment Tool was more accurate. Tools which have unknown validity and reliability should not be used. Future research is needed to provide evidence that use of falls risk assessments has a positive impact on reducing patient falls.