Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adherence to medication
RCT	230 male steelworkers, with hypertension, not on current treatment. Of 115 in each group, 80 (70%) in education group and 64 (56%) in no education group received drug treatment. These 144 men were analysed	Assessment by pill count (compliance defined as the % of medication prescribed that was removed from the bottle; defined as "compliant" if compliance pill count of 80% or more) 6 months follow-up 40/80 (50%) with educational intervention 36/64 (56%) with no health education	Similar rates of adherence between groups, but differences not tested statistically
RCT	110 people, mean age 56 years, started on lipid-lowering medication (fluvastatin) mainly for primary prevention	Outcome (% of pills taken assessed by pill count) follow-up at 4 months 88% with educational intervention 84% with usual care Absolute numbers not reported	P >0.05		Not significant
RCT	110 people, with either newly diagnosed or established treated hypertension, mean age 59 years	Adherence assessed by pill count 6 months follow-up 93% with educational intervention 69% with usual care Absolute numbers not reported	P <0.002	Effect size not calculated	educational intervention
RCT	110 people, with either newly diagnosed or established treated hypertension, mean age 59 years	Adherence assessed by pill count 2 years' follow-up 96% with educational intervention 56% with usual care Absolute numbers not reported	P <0.001	Effect size not calculated	educational intervention
RCT 4-armed trial	115 people attending a primary care clinic, <70 years old, with hypertension, living near to clinic	Self-reported compliance (survey conducted by nurse, household medicated survey, which included questions on drugs and a count of all hypertensive medications; outcome reported as absolute numbers of "good", "fair", and "poor" compliance) 8 people reported as "good", 13 "fair", 8 "poor" with educational intervention 7, 13, 5 people with daily self-monitoring of blood pressure 9, 15, 6 people with education and self-monitoring of blood pressure 7, 12, 10 people with control	RCT reported "no significant difference between groups on compliance"		Not significant
RCT 3-armed trial	417 people with hypertension, on medication	Self-reported compliance at interview 91% with educational intervention 90% with no education Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT 3-armed trial	417 people with hypertension, on medication	Analysis of number of tablets prescribed by pharmacy records 69% with educational intervention 68% with no education Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	34 people with hypertension on treatment, age 16 years or older (average age 51–56 years), at tertiary care medical centre	Self-reported compliance as assessed by interview with questionnaire (score measured on 6-point scale, where 0 = no adherence and 5 = all tablets taken) (possible total score of 30) 6 months 27.53 with educational intervention 24.46 with usual care	P = 0.05		Not significant
RCT	34 people with hypertension on treatment, age 16 years or older (average age 51–56 years), at tertiary care medical centre	Physician's assessment of adherence (score measured on 6-point scale, where 0 = no adherence and 5 = all tablets taken) (possible total score of 30) 6 months 29.18 with educational intervention 23.9 with usual care	P = 0.003 Not clear on what basis the physician’s assessment of adherence was made	Effect size not calculated	educational intervention
RCT	Participants chosen from database by prescription (rather than diagnosis), 410 people taking benazepril, 1728 taking metoprolol, and 568 taking simvastatin, mean age 55 years (range 20–97 years), with refill of medication every 30 days Subgroup analysis	Index of compliance was medication possession ratio (MPR), calculated from pharmacy records (MPR defined as the number of days' supply of medication obtained throughout the study period expressed as a ratio against the number of days that should have been supplied) over 9 months 0.71 with educational intervention 0.72 with usual care	Reported as not significant P value not reported		Not significant
RCT	Participants chosen from database by prescription (rather than diagnosis), 410 people taking benazepril, 1728 taking metoprolol, and 568 taking simvastatin, mean age 55 years (range 20–97 years), with refill of medication every 30 days Subgroup analysis	Index of compliance was medication possession ratio (MPR), calculated from pharmacy records (MPR defined as the number of days' supply of medication obtained throughout the study period expressed as a ratio against the number of days that should have been supplied) over 9 months 0.74 with educational intervention 0.73 with usual care	Reported as not significant P value not reported		Not significant
RCT	Participants chosen from database by prescription (rather than diagnosis), 410 people taking benazepril, 1728 taking metoprolol, and 568 taking simvastatin, mean age 55 years (range 20–97 years), with refill of medication every 30 days Subgroup analysis	Index of compliance was medication possession ratio (MPR), calculated from pharmacy records (MPR defined as the number of days' supply of medication obtained throughout the study period expressed as a ratio against the number of days that should have been supplied) over 9 months 0.73 with educational intervention 0.70 with usual care	Reported as not significant P value not reported		Not significant
RCT	100 people >70 years of age with chronic stable heart failure, average age 85 years, excluded if mobility disorder or if Folstein's Mental Health test score was <21	Mean compliance, expressed as % of maximum number of tablets that should have been consumed (assessed by pill count) 93% with educational intervention 51% with control Absolute numbers not reported	P <0.001	Effect size not calculated	educational intervention
RCT	245 people with hypertension, on 1 or more medications, attending primary care	Adherence measured by electronic medication monitor (electronic lid that registered time and date of opening); mean "timing compliance" defined as number of doses taken at 24- or 12-hour intervals for a once- or twice-daily regimen respectively, divided by the total number of days x 100% 6 months 87% with educational intervention 90% with usual care Absolute numbers not reported	Adjusted difference between means –1 95% CI –5.1 to +3.1 P = 0.63		Not significant
RCT	314 people with heart failure, 50 years or older, attending primary care, on at least 1 medication	Adherence measured by electronic medication monitor (electronic lid that registered time and date of opening); "taking adherence" was defined as the % of prescribed medication taken over 9 months 79% with educational intervention 68% with usual care Absolute numbers not reported	Difference +11% 95% CI +5.0% to +16.7%	Effect size not calculated	educational intervention
RCT	314 people with heart failure, 50 years or older, attending primary care, on at least 1 medication	Adherence measured by electronic medication monitor (electronic lid that registered time and date of opening); "scheduling adherence" was defined as day-to-day deviation in timing of dose (e.g., once-daily within 2.4 hours of dose on previous day) over 9 months 53% with educational intervention 47% with usual care Absolute numbers not reported	Difference +6% 95% CI +0.4% to +11.5%	Effect size not calculated	educational intervention
RCT	314 people with heart failure, 50 years or older, attending primary care, on at least 1 medication	Adherence measured by electronic medication monitor (electronic lid that registered time and date of opening); "taking adherence" was defined as the % of prescribed medication taken 3 months after intervention had finished 71% with educational intervention 67% with usual care Absolute numbers not reported	Difference +4% 95% CI –2.8% to +10.7%		Not significant
RCT	314 people with heart failure, 50 years or older, attending primary care, on at least 1 medication	Adherence measured by electronic medication monitor (electronic lid that registered time and date of opening); "scheduling adherence" was defined as day-to-day deviation in timing of dose (e.g., once-daily within 2.4 hours of dose on previous day) 3 months after intervention had finished 48.9% with educational intervention 48.6% with usual care Absolute numbers not reported	Difference +0.3% 95% CI –5.9% to +6.5%		Not significant
RCT	636 adults with hypertension, attending primary care, using hypertensive medication at the time of baseline visit	Increase in self-rated adherence (assessed using the 4-item Morisky Self-reported Medication-Taking Scale), reported as a % 9% with nurse-delivered educational/behavioural intervention by protocol, bi-monthly via telephone for 2 years 1% with usual care Absolute numbers not reported
RCT	190 African-Americans with hypertension (88% women; mean age 54 years), attending community-based primary care practices	Adherence measured by electronic pill monitors 12 months 57% with research assistant (RA)-delivered motivational interviewing (MINT) sessions at 3, 6, 9, and 12 months 43% with usual care Absolute numbers not reported	Difference –14% 95% CI –0.2% to –27% P = 0.027	Effect size not calculated	MINT
RCT	450 people with hypertension attending primary care	Overall compliance rate (individuals with a treatment compliance of 80–110%) 24 weeks 83% with educational magazine sent to the patient's home twice monthly 49% with usual care Absolute numbers not reported	P = 0.0001	Effect size not calculated	educational magazine
RCT	450 people with hypertension attending primary care	Correct time compliers 24 weeks 74% with educational magazine sent to the patient's home twice monthly 42% with usual care Absolute numbers not reported	P = 0.0001	Effect size not calculated	educational magazine