1. Michael J. Mugavero, M.D., MHSc, Jessica A. Davila, Ph.D., Christa R. Nevin, MSPH, and Thomas P. Giordano, M.D., M.P.H. Volume 24, Number 10, 2010 AIDS PATIENT CARE and STDs

2. Access to care has long been recognized as a vital factor in promoting and sustaining health engagement means the processes of linkage to care and retention in care

3. Engagement Delayed linkage and poor retention in outpatient HIV care → delayed receipt of antiretroviral medications, higher rates of viral load failure, and increased morbidity and mortality patients engaged in clinical care, better retention → reduced risk transmission, viral load suppression Retention in care is being recognized as a crucial step in maximizing patient outcomes

4. We reviewed the available published literature and summarized findings of the most commonly used measures to ascertain retention in outpatient HIV medical Measures of retention in care – Studies have typically included only scheduled outpatient medical appointments HIV biomarkers have been used to measure linkage and retention in HIV care, acting as a surrogate for a completed visit

6. Missed visits 1, 4, 0, 1 Appointment adherence 80%, 33%, 100%, 66% Visit constancy 100%, 50%, 75%, 25% Gaps in care B, D had a gap of over 6 months HRSA HAB medical visits performance measure A, B, and C had 2 visits, D not

8. The clinician’s perspective missed visits and gap in care as intuitive measures of retention Patient’s patterns of missed visits are likely taken into account by providers in determining the time interval for a subsequent clinic visit studies have shown these 2 measures associated with patient outcomes including clinical events and mortality.

9. The administrator’s perspective Appointment adherence and HRSA HAB may be preferable for administrators allow for longitudinal tracking of retention in care and also for setting an overall clinic benchmark (e.g., >80%) inform local, regional and/or national planning and resource allocation

10. Researcher’s perspective The missed visits measure has been widely used particularly for preliminary research and short-term observation periods. appointment adherence and visit constancy may be preferable for research purposes, particularly for longer observation periods

11. Requisite clinic visit data visit constancy, gaps in care, and the HRSA HAB are calculated based on completed visits only only ‘‘no show’’ visits have been included in the missed visit and appointment adherence, but there are issues related to the timing of cancelled visits worth noting

12. Impact of clinic scheduling practices Clinics with automatic rescheduling of missed visits may lead to artificially poor missed visit and appointment adherence results Considerable variability exists among HIV clinics in the availability and approach to handling unscheduled or acute care visits

13. Computational issues missed visits and appointment adherence – simplest gaps and HRSA HAB – calculation of the time interval between completed visits Constancy – the observation period of interest be divided into intervals of interest

14. Sensitivity in capturing disease severity and stage of treatment HRSA HAB, the gaps – insensitive in capturing retention as it relates to issues of disease severity and stage, and rather represents a minimum standard of retention in care missed visit and appointment adherence – visit frequency reflects the disease severity and stage of treatment for each individual patient constancy – the capacity to account for severity and stage of treatment through variation of the time interval

15. With growing emphasis on ‘‘test and treat’’ approaches to HIV prevention, there is a clear need for additional engagement in HIV care research future research should evaluate the impact of such visits and their inclusion in HIV retention measures on patient outcomes

16. This article provides a synthesis of the most commonly used measures of retention in HIV care, their methodological and conceptual strengths and limitations, and suggests situations in which certain measures may be preferred over others