Objectives: Questionnaire-style outcome measures are often used in clinical trials. It is unclear whether this type of outcome measurement can capture change that is personally meaningful to individuals. In contrast, Goal Attainment Scaling (GAS) is an outcome measure where patients and clinicians develop and track an individualized set of treatment-related goals that are important to the patient. Here, we compared attainment of daily function goals to questionnaire-style measures of function in two mild-moderate dementia clinical trials.

Methods: Data were from the Atlantic Canadian Alzheimer Disease Investigation of Expectations (ACADIE) and the Video Imaging Synthesis of Treating Alzheimer disease (VISTA) trials. Both used GAS as a primary outcome. ACADIE used the Functional Assessment Questionnaire, Lawton-Brody Physical Self-Maintenance Scale, and Lawton-Brody Instrumental Activities of Daily Living which we normalized to a 100-point scale. The VISTA trial used the 100-point Disability Assessment for Dementia to assess function.

Results: Subjects were demographically comparable between ACADIE and VISTA (75.9±7.8, 76.3±7.6 years of age; 73%, 64% women; and baseline Mini-Mental State Examination scores 19.7±5.2, 20.8±3.3), respectively. Baseline function scores were near-normal in ACADIE (mean=46.8±15.2, median=44) and negatively skewed in VISTA (mean=76.3±19.7, median=83). Patient-rated daily function goal attainment correlated with change in questionnaire-based measures of function (ACADIE: r=0.25, p=0.022; VISTA: r=0.37, p=0.044) but clinician-rated daily function GAS was not correlated in VISTA (ACADIE: r=0.60, p<0.001; VISTA: r=0.07, p=0.7). There was no change in daily function GAS (ACADIE: mean=50.6±9.4, p=0.6; VISTA: mean= 51.5±14.2, p=0.5), but questionnaire-based measures of function declined (ACADIE: mean change=-3.6±10.0, p<0.001; VISTA: -5.2±11.8, p=0.003).

Conclusions: Questionnaire-style outcome measures were correlated with patient-rated daily function GAS goals. However, GAS clearly showed that patients maintained important aspects of daily living when questionnaire-based measures showed net decline. Individualized outcome measures like GAS can detect meaningful change that could be missed by standard outcome assessments.