Context
A validated 82-item Advance Care Planning (ACP) Engagement Survey measures a broad range of behaviors. However, concise surveys are needed.
Objectives
To validate shorter versions of the Survey.
Methods
The Survey included 57 process (e.g. readiness) and 25 action items (e.g. discussions). For item reduction, we systematically eliminated questions based on face validity, item non-response, redundancy, ceiling effects, and factor analysis. We assessed internal consistency (Cronbach’s alpha) and construct validity with cross-sectional correlations and the ability of the progressively shorter survey versions to detect change one week after exposure to an ACP intervention (Pearson’s correlation coefficients).
Results
501 participants (4 Canadian and 3 US sites) were included in item reduction (mean age 69 years (±10), 41% non-white). Due to high correlations between readiness and action items, all action-items were removed. Due to high correlations and ceiling effects, 2 process-items were removed. Successive factor analysis then created 55, 34, 15, 9, and 4-item versions. 664 participants (from 3 US ACP clinical trials) were included in validity analysis (age 65 years (±8), 72% non-white, 34% Spanish-speaking). Cronbach’s alphas were high for all versions (4-item, 0.84–55-item, 0.97). Compared to the original survey, cross-sectional correlations were high (4-item, 0.85–55-item, 0.97) as were delta correlations (4-item, 0.68–55-item, 0.93).
Conclusion
Shorter versions of the ACP Engagement Survey are valid, internally consistent, and able to detect change across a broad range of ACP behaviors for English and Spanish speakers. Shorter ACP Surveys can efficiently measure broad ACP behaviors in research and clinical settings.