Marquez Contreras 2006.

Methods	The patients (n = 250) were randomly assigned to one of the 2 groups, stratified by age and sex: a control group (CG) and an intervention group (IG). The randomization process was centralized and blind, performed using random number tables and by a person not involved in the follow‐up
Participants	Patients were ambulatory patients between 18 and 80 years of age, newly diagnosed hypertensive patients or those already on antihypertensive treatment but not controlled and who did not have an electronic monitor for home blood pressure measurement (HBPM), patients with phase I or II arterial hypertension (AHT) according to the JNC‐VI criteria, and patients who had given their written consent. Patients were excluded from the study if they were requiring 2 or more antihypertensive drugs at the start of the study, secondary AHT, pregnant or breast‐feeding women, patients with diseases that could interfere with the study, patients who intended to donate blood, patients who were unable to give their consent, patients participating in other studies, and patients co‐habiting with other individuals taking the same antihypertensive medication
Interventions	Patients in this intervention, apart from receiving the usual care, also received an OMRON automatic monitor for home blood pressure measurement (HBPM). The patients received a kit in their home containing the monitor, an instruction manual, a summary of the functions, and a card on which to note the measurements. They were advised to follow the HBPM program, which consisted of measuring the BP 3 days a week (Tuesdays, Thursdays, and Saturdays), twice before breakfast (0800 to 1000 hours) and twice before supper (2000 to 2200 hours) and record these results on the card (4 times a day). The patients received a phone call to explain how to use the monitor and follow the HBPM program. The control intervention involved patients receiving the care usually provided by their general practitioners
Outcomes	Compliance was measured using Medication Event Monitoring System (MEMS) and the percentage compliance (PC) was calculated by dividing the total number of tablets the patients were assumed to have taken by the total number of tablets that the patients should have taken and multiplying by 100 to obtain a percentage. Compliance was considered to be present in patients with a percentage compliance between 80% and 100% Blood pressure (taken as the mean of 2 measurements) was the clinical outcome used
Notes	―
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization done using random number table. (pg 170) "The patients were randomly assigned to one of the two groups, stratified by age and sex. The randomization process was centralized and blind, performed using random number tables and by a person not involved in the follow‐up."
Allocation concealment (selection bias)	Low risk	Allocation concealment completed. (pg 170) "The patients were randomly assigned to one of the two groups, stratified by age and sex. The randomization process was centralized and blind, performed using random number tables and by a person not involved in the follow‐up."
Selective reporting (reporting bias)	Unclear risk	No protocol available
Other bias	Unclear risk	No mention of limitations in discussion or other clear biases
Blinding of outcome assessment (detection bias) Adherence measure	Unclear risk	(PRIMARY) MEMS ‐ No mention of blinding of outcome assessors. (pg 174) "The methodology has been correct: a randomized, double‐blind trial"
Blinding of outcome assessment (detection bias) Patient outcome	Unclear risk	(PRIMARY) BLOOD PRESSURE MEASUREMENT ‐ Method of blinding not described but less likely to affect BP reading ‐ electronic measurement. (pg 174) "The methodology has been correct: a randomized, double‐blind trial"
Blinding of participants (performance bias) Adherence measure	Unclear risk	(PRIMARY) MEMS ‐ No mention of blinding of patients. MEMS is obtrusive but objective measure. (pg 174) "The methodology has been correct: a randomized, double‐blind trial"
Blinding of participants (performance bias) Patient outcome	Low risk	(PRIMARY) BLOOD PRESSURE MEASUREMENT ‐ Objective outcome but no mention of blinding of patient
Blinding of personnel (performance bias) Adherence measure	Unclear risk	(PRIMARY) MEMS ‐ Uncertain mention of blinding of study personnel. (pg 174) "The methodology has been correct: a randomized, double‐blind trial"
Blinding of personnel (performance bias) Patient outcome	Unclear risk	(PRIMARY) BLOOD PRESSURE MEASUREMENT ‐ Method of blinding not described but less likely to affect BP reading ‐ electronic measurement. (pg 174) "The methodology has been correct: a randomized, double‐blind trial"
Incomplete outcome data (attrition bias) Adherence measure	Unclear risk	(PRIMARY) MEMS ‐ Usable sample size did not meet power calculations ‐ 200 versus 250 (80% of power calculation). Missing data uniform across groups ‐ 13 each. Statistically significant difference only in diastolic BP. Not sure whether the missing data and reduced sample size could have affected the result. (pg 171) "A total of 250 patients were included, with data being obtained from 226. Of these, compliance data were obtained in 200 subjects (88.49% of the sample), with 26 subjects withdrawing from the study, 13 from the GC and 13 from the IG (P ¼ NS). Four of these were as a result of adverse events, 10 because of travel or change of address, one because of the intention to become pregnant, one because of the detection of secondary AHT (CG), four did not attend the scheduled visits, and six withdrew as a result of the malfunctioning of the MEMS."
Incomplete outcome data (attrition bias) Patient outcome	Unclear risk	(PRIMARY) BLOOD PRESSURE MEASUREMENT ‐ Usable sample size did not meet power calculations ‐ 200 versus 250 (80% of power calculation). Missing data uniform across groups ‐ 13 each. Statistically significant difference only in diastolic BP. Not sure whether the missing data and reduced sample size could have affected the result. (pg 171) "A total of 250 patients were included, with data being obtained from 226. Of these, compliance data were obtained in 200 subjects (88.49% of the sample), with 26 subjects withdrawing from the study, 13 from the GC and 13 from the IG (P ¼ NS). Four of these were as a result of adverse events, 10 because of travel or change of address, one because of the intention to become pregnant, one because of the detection of secondary AHT (CG), four did not attend the scheduled visits, and six withdrew as a result of the malfunctioning of the MEMS."