| Transition-package | Characterise Transitions in Test Result Status in Longitudinal Studies | 
| add_prev_date | Find Previous Test Date for Subject | 
| add_prev_result | Find Previous Test Result for Subject | 
| add_transitions | Identify Temporal Transitions in Longitudinal Study Data | 
| Blackmore | Exercise Histories of Eating-Disordered and Control Subjects | 
| get_prev_date | Find Previous Test Date for Subject | 
| get_prev_result | Find Previous Test Result for Subject | 
| get_transitions | Identify Temporal Transitions in Longitudinal Study Data | 
| PreviousDate | Find Previous Test Date for Subject | 
| PreviousResult | Find Previous Test Result for Subject | 
| Transition | Characterise Transitions in Test Result Status in Longitudinal Studies | 
| Transitions | Identify Temporal Transitions in Longitudinal Study Data | 
| uniques | Unique Values for Subject, Timepoint and Result |