Summary of the Studies Included in Literature Review by Type of Medication

AuthorNAgeDesignMeasuresMean Adherence% Patients Adherent
Kinney et al 199929845–15 yMultisite RCT (HUG-KIDS)Pill count: entire 2-wk supply taken74%
Ware et al 20023053a5–15 yMultisite RCT (HUG-KIDS)Pill count: % of 2-wk supply taken94.4%
Olivieri and Vichinsky 19985510b5–18 ySingle-site prospective cohortMEMS caps: % of pills taken96%
Thornburg et al 201031153c9 m–1.5 yMultisite RCT (Baby HUG)≥80% of liquid medication taken by volume remaining at study visitConsumed 102% of volume prescribed89% took >80% doses
Thornburg 20103275<18 ySingle-site cross-sectional studyVisual analog scale: >75% dosesVisual analog: 82%
Morisky scale: ≤1Morisky: 84%
Clinician estimate: “often” or “always” adherentClinician report: 85%
Refills: ≥5 in 6 moRefills: 49%
Alvarez et al 200934217–21 yMultisite prospective cohortPill count: ≥80% doses takenPill count mean 79%Parent report: 71%
Parent report: ≥80% doses takenPill count: 43%
Raphael et al 20094559Pediatric patientsSingle-site retrospective cohortMedical record: missed ≥3 doses a month for ≥2 mo76%
Thuret et al 20093570≥6 yMultisite cross-sectionalMorisky scale: 3 or 4Morisky scale: 72%
Parent or patient report: no missed infusionsParent report: 43%
Treadwell and Weissman 200136316–21 ySingle-site prospective cohortPatient report: used in last 2 d57%
Treadwell et al 20054215Pediatric patientsSingle-site cross-sectionalRefills: % dosesRefill: 60% doses
Parent report: days since last deferoxamineDays: 8.7
Morisky scaleMorisky scale: 2.0
Number physical signs of chelationPhysical signs: 2.1
Oral Antibiotic Prophylaxis
Berkovitch et al 199850459 m–7 ySingle-site prospective cohortMEMS caps: % doses69%N/A
Davis 1989565192 m–5 yMultistate retrospective claim-basedLow estimate: MPR ≥.3369%–84%
High estimate: same formula, assumes did not take after expired
Sox et al 200341261<4 yMultistate retrospective claim-basedRefills: days covered by medication fills in 1-y period40%
Buchanan et al 198257626 m–19 ySingle-site prospective cohortUrine test +66%
Pejaver et al 1997474211 m–12 ySingle-site prospective cohortUrine test +; Parent report: never missed doseUrine: 46%
Parent report: 62%
Cummins et al 19912750≤16 ySingle-site cross-sectionalUrine test +; Parent report: never missed doseUrine: 47%
Parent report: 62%
Teach et al 1998581590.3–24 ySingle-site prospective cohortUrine test +; Parent or patient report: gave dose in last 15 hUrine: 43%
Parent report: 68%
Bitarães et al 2008591083 m–4.5ySingle-site prospective cohortUrine test +; Parent report: never missing doseUrine: 56%
Medical record: record of nonadherenceParent report: 48%
Medical record: 89%
Elliot et al 200140506 m–5 ySingle-site retrospective cohortRefill: in past 14 d and average time between 14-d supply27 dRefill: 12%
Parent report: of “never late to get refillsParent report: 60%
Witherspoon and Drotar 200639306 m–6 ySingle-site prospective cohortRefill: ≤1 uncovered day per monthRefill: 33%
Parent report: miss <2 d per monthParent report: 57%
Clinician report: very adherentClinician report: 50%
IM or IV Antibiotic Prophylaxis
King et al 201160784 m–4 ySingle-site retrospective cohortAdministration record: 80% injections received89%
Multiple Medications
Patel et al 201028936 m–20 ySingle-site retrospective cohortMean MPRPenicillin MPR: 55%
Hydroxyurea MPR: 61%
Folic acid MPR: 61%
Babiker 198637402–5 ySingle-site prospective cohortUrine test +; Administration record: % indicated injections receivedInjections: 92%Urine (oral antibiotic): 40%
Babiker 198638424–8 ySingle-site prospective cohortUrine test +; Administration record: % indicated injections receivedInjections: 95%Urine (oral antibiotic): 44%
  • RCT, randomized controlled trial.

  • a Only includes patients who received maximum tolerated doses.

  • b 17 patients in effectiveness study, only 10 received MEMS caps.

  • c 191 patients in study, adherence data available for 153 subjects.