Table 2.
Preliminary and revised categories and definitions of nonadherence measurement approaches
| Preliminary Framework included in Survey 1 | Revised Framework included in Survey 2 |
|---|---|
| Self-report (100%) Patients report on their medication-taking behavior using a structured set of questions and response scales; may be administered orally by an interviewer or in self-administered format (paper or computer) |
Self-report Patients report on their medication-taking behavior using a structured set of questions and response scales; may be administered orally by an interviewer or in self-administered format (paper or computer) |
| Proxy report (94%) A patient’s caregiver or health care provider reports on a patient’s medication-taking behavior using a structured set of questions and response scales; may be administered orally by an interviewer or in self-administered format (paper or electronically) |
|
| Prescription fill data from pharmacy, insurance, or other administrative database (100%) Data are obtained from a clinic, healthcare system, payer, or pharmacy on prescriptions dispensed to patients, including medication identifiers (e.g., medication name, therapeutic class, National Drug Code), dates of refills, and quantity/days’ supply dispensed. The data are used to quantify medication coverage and/or gaps over a time period of interest (e.g., proportion of days covered, medication possession ratio) |
Prescription fill data from pharmacy, insurance, or other administrative database Data are obtained from a clinic, healthcare system, payer, or pharmacy on prescriptions dispensed to patients, including medication identifiers (e.g., medication name, therapeutic class, National Drug Code), dates of refills, and quantity/days’ supply dispensed. The data are used to quantify medication coverage and/or gaps over a time period of interest (e.g., proportion of days covered, medication possession ratio) |
| Dose or pill count (92%) The number of doses remaining in a medication container (e.g., pill bottle, blister pack, or inhaler with dose counter) are counted, and a comparison is made of how many doses are supposed to be left versus how many are left. Dose counts can be conducted in different settings including office visits at which patients bring their medication containers, at home visits, and telephone visits at which patients gather all their medications |
Dose or pill count The number of doses remaining in a medication container (e.g., pill bottle, blister pack, or inhaler with dose counter) are counted, and a comparison is made of how many doses are supposed to remain versus how many remain. Pill counts can either be announced or unannounced, and can take place in different settings, including office visits at which patients bring their medication containers, home visits, and telephone visits at which patients gather all their medications |
| Electronic drug monitoring (100%) Medications are put into a bottle or other device with a sensor that records the date and time when the device was opened. Data can be used to calculate the correct timing adherence (% doses taken within specific time intervals), correct dosing adherence (% days with correct number of pill bottle openings), and adherence (% prescribed doses taken over a time period) |
Electronic drug monitoring Medications are put into a bottle or other device with a sensor that records the date and time when the device is opened. Data can be used to calculate the correct timing adherence (% doses taken within specific time intervals), correct dosing adherence (% days with correct number of pill bottle openings), and adherence (% prescribed doses taken over a time period) |
| Drug or drug metabolite level (96%) A blood, urine, or other biospecimen is taken, and the level of the drug of interest or its metabolite is measured in a laboratory |
Drug or drug metabolite level A blood, urine, or other biospecimen is taken, and the level of the drug of interest or its metabolite is measured in a laboratory |
| Biomarkers (63%) A biospecimen is taken (e.g., blood), and the level of a biomarker of the drug’s effect is used to assess adherence (e.g., LDL level to assess adherence to statins). Alternatively, a physiologic measurement is taken (e.g., blood pressure), and the measure is used to assess adherence to a medication (e.g., antihypertensive) |
Biomarkers
A biospecimen is taken (e.g., blood), and the level of a biomarker of the drug’s effect is used to assess adherence (e.g., LDL level to assess adherence to statins). Alternatively, a physiologic measurement is taken (e.g., blood pressure), and the measure is used to assess adherence to a medication (e.g., antihypertensive) |
| Ingestible sensors (74%) Patients take medication with an ingestible sensor that transmits a signal to an electronic device when the sensor is ingested |
Smart technology (ingestible sensors) Patients ingest a pill or wear a device that passively or actively transmits a signal to an electronic device near or on the body (e.g., patch, breathing tube, wrist-worn device) to track whether a medication was taken |
| Direct observation (71%) Patients report to a location where a staff member watches them take a medication |
Direct observation A staff member observes a patient taking a medication, either in person or remotely by video |
Survey respondents were asked whether they agreed or disagreed with each of these approaches. In survey 1, percent agreement with inclusion of each nonadherence behavior is provided in parentheses; consensus with classification was viewed as present if >70% of respondents agreed with inclusion. In survey 2, percent agreement with changes made to survey are provided in parentheses in right column. Bold indicates words that were removed and italics indicates words that were added.