Objective: To identify diagnostic groups and the form of the trajectory of functional decline that has the potential to enhance advance care planning (ACP) in a nursing home (NH) population.

Methods: Retrospective, longitudinal study with dependent variable (function) derived from the Resident Classification Scale (RCS), 1997-2008. Trajectory modelling used linear and curvilinear terms.

Results: The organ failure or other residents have a linear average functional decline. The organ failure residents had an average decline of 6.5 points per year and average function score at death of 68.6, CI [62.4, 74.8]. The cancer and frailty residents had significant curvilinear terms. The frailty residents had a slower rate of decline at 9.54 points per year and were most care dependent at death, with an average function score of 77.1, CI [73.8, 80.9].

Conclusion: Functional change is a measurable variable for a predictive tool to enhance ACP for NH residents based on their diagnosis.