Please cite use of PhenX protocols in your presentations and publications as:
Protocols incorporated in this study were selected from the PhenX Toolkit version
March 17, 2023, Ver 45.0 .
DD = Data Dictionary
DCW = Data Collection Worksheet
Gill, T.M., et al. A program to prevent functional decline in physically frail, elderly persons who live at home. NEW ENGL J MED, 2002