Validation of the Fracture Mobility Score against the Parker Mobility Score in hip fracture patients

Abstract

Introduction: The Parker Mobility Score has proven to be a valid and reliable measurement of hip fracture patient mobility. For hip fracture registries the Fracture Mobility Score is advised and used, although this score has never been validated. This study aims to validate the Fracture Mobility Score against the Parker Mobility Score.

Patients and methods: The Dutch Hip Fracture Audit uses the Fracture Mobility Score (categorical scale). For the purpose of this study, five hospitals registered both the Fracture Mobility Score and the Parker Mobility Score (0-9 scale) for every admitted hip fracture patient in 2018. The Spearman correlation between the two scores was calculated. To test whether the correlation coefficient remained stable among different patient subgroups, analyses were stratified according to baseline patient characteristics.

Results: In total 1,201 hip fracture patients were included. The Spearman correlation between the Fracture Mobility Score and Parker Mobility Score was strong: 0.73 (p = < 0.001). Stratified for gender, age, ASA score, dementia, Index of Activities of Daily Living (KATZ-6 ADL score), living situation and nutritional status, the correlation coefficient varied between 0.40-0.84. For patients aged 90 and over and having an ASA score of III-IV who suffered from dementia, had a KATZ-6 ADL score of 1-6, lived in an institution and/or were malnourished, the correlation was moderate.

Conclusion: The Fracture Mobility Score is overall strongly correlated with the Parker Mobility Score and can be considered as a valid score to measure hip fracture patient mobility. This may encourage other hip fracture audits to also use the Fracture Mobility Score, which would increase the uniformity of mobility score results among national hip fracture audits and decrease the overall registration load.

Keywords: Audit; Fracture Mobility Score; Hip Fracture; Parker Mobility Score.