In summary, we have shown that summary measures of adherence in two recent HIV prevention trials of acyclovir varied considerably depending on assumptions and analysis method.
Trials often report simple summary measures of adherence, with heterogeneity in calculation of these summary measures [ 15– 15].
To calculate a summary measure of adherence, assumptions must be made about the number of tablets taken for those visits.
Dietary intake was assessed using a semiquantitative food frequency questionnaire consisting of 126 items developed by Willett et al. (10) Then, the recently validated 2005 Dietary Guidelines Adherence Index (DGAI) (4) was used as a summary measure of adherence to the 2005 Dietary Guidelines (11).
Summaries of optimal adherence, such as the proportion of person years with adherence ≥90%%, may give a better reflection of actual product use, but are more sensitive to assumptions made about intervals with unknown adherence, particularly when the amount of missing data is large.
A summary of the individual adherence items was calculated as the mean of the three individual items.
In summary, participant-dependent measures of adherence were unreliable in FEM-PrEP.
Summary adherence variables of percent of doses taken and percent of doses taken on time for the 30 day period before each assessment visit were then calculated for each participant.
Pharmaceutical interventions with the patient can comprise counseling of the patient and caregiver about correct drug usage, allocation of a drug dispenser, the provision of information leaflets about correct drug intake (short version of the summary of product characteristics), written adherence support strategies.
Although all summary measures provide an imperfect assessment of adherence, overall adherence, since it takes into account the total days that each participant is in the trial, may provide a reasonable reflection of drug exposure on average over the duration of the trial.
