Dementia is a neurodegenerative disease where functional ability in individuals with dementia (IWD) declines over time. The majority of care costs in IWD are directly attributed to functional disability (Zhu et al., 2006). Compromised functional ability is unsafe for IWD, anxiety provoking for families, and costly to health care organizations. Valid and reliable clinical information about functional ability can be used to individualize care and design safe and supportive environments thereby promoting the highest level of independence for individuals with dementia. Therefore, an effective and efficient method for measuring functional ability is important.