How to investigate Adherence to Antiretroviral Treatment ... - INRUD

Chapter 2. Core Indicators of Adherence
the four feasibility trials, the median number of days covered in each country was above 90
percent. However, when looking at facilities the lowest was 53 percent. If on average patients
only had 53 percent of their days covered by medicines, then good adherence levels are
impossible and an intervention is greatly needed.
With the data collection forms to generate the indicators, it is necessary to write down each
attendance over the last six months and the numbers of days of ARVs dispensed.
Indicator 2. Average percentage of days covered by ARVs dispensed for a sample of
patients for a defined period (180 days).
Rationale
Source of data
Data collection
Computation
Comments
Pitfalls
Adherence measures from pharmacy refill rates have been shown to
correspond to clinical outcomes. If there are too few days of medicine
dispensed, then we infer that the patient has missed doses.
Pharmacy records
Based on the sample of 100 patients who visited the pharmacy during the
seventh month before data collection (the index visit) and using historical
dispensing data in pharmacy records, identify the date and days’ supply of
all ARVs dispensed during the index visit and during all subsequent visits
for this patient during the follow-up period chosen. If the number of days’
supply in the last dispensing during the follow-up period is greater than the
number of days left in the period, count only the days’ supply equal to the
number of days left in the period. This is done automatically if the data
entry sheet is used.
For individual patient: Long-term adherence—(Total number of days’ ARV
supply dispensed/number of days in period) × 100
Note: If any long-term adherence rate is >100 percent, then change it to
100 percent
For facility: Average percent long-term adherence—Sum of sampled
patient long-term adherence rates/number of sampled patients
If the patient has more than one ARV in the treatment regimen, this
indicator should be calculated for the least supplied medication, as any part
of a dose missed is a missed dose.
Note: The computation is automatic on the spread sheet analysis tool. The
tool is an MS Excel spreadsheet supplied with the manual where the data
entry forms look like the hand written data entry forms. Data needs double
entry for each facility onto the spread sheets. There is a separate
consolidation file in which the summary data for each facility are imported
and the indicators automatically generated.
Pharmacy dispensing records are useful for measuring long-term adherence,
but this method makes assumptions about completeness of the dispensing
data and about how the medicines were consumed.
Identifying reliable patient-specific longitudinal records may be a problem
in some systems; the records are usually easily retrievable (e.g., dispensings
recorded on a single page or in a consistent place in the clinical record).
However some data may be inconsistently recorded, so a low measure on
the indicator may reflect poor record keeping.
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