Table 1. Study design and patient characteristics.
| Study, year | Country | Control | No of participants (R/C) | Drug adherence assessment | No of drugs at baseline (R/C) | No of drugs at follow-up (R/C) | Drug change rates (R/C) | Jadad score |
| SYMPLICITY HTN-2, 2010 | Europe, Australia, NZ | Usual drugs | 106 (52/54) | Diary | 5.2/5/3 | -/- | 33 (28.6/17.6) | 3 |
| SYMPLICITY HTN-3, 2014 | USA | Sham + usual drugs | 535 (364/171) | Diary | 5/1/5/2 | 5.0/5.2 | 39 (38/40) | 5 |
| OSLO, 2014 | Norway | Drugs | 19 (9/10) | Witnessed intake | 5/1/5/0 | 4.9/5.2 | 31.5 (11.1/50.0) | 3 |
| PRAGUE-15, 2015 | Czech Republic | Drugs + spironolactone | 106 (52/54) | Plasma drug conc. | 5.1/5.4 | 5.0/5.6 | - (-/-) | 3 |
| DENERHTN, 2015 | France | SSAHT | 101 (48/53) | Morisky score | 43527 | 5.3/5.4 | - (-/-) | 3 |
| SYMPLICITY FLEX, 2015 | Germany | Sham + usual drugs | 71 (35/36) | Ineriew | 4.4/4.3 | -/- | 21 (-/-) | 5 |
| SYMPLICITY HTN-JAPAN, 2015 | Japan | Usual drugs | 41 (22/19) | Diary | 4.9/4.9 | 4.9/4.9 | 7.3 (9.1/5.3) | 3 |
| RESET, 2016 | Denmark | Sham + usual drugs | 69 (36/33) | Diary | 4.1/4.2 | 4.1/4.2 | 39 (46/33) | 5 |
| DENERVHTA, 2016 | Spain | Usual drugs + spironolactone | 24 (11/13) | Haynes-Sackett test | 4.3/3.9 | -/- | 29 (27/30) | 3 |
| SYMPATHY, 2017 | Netherlands | Usual drugs | 139 (95/44) | Plasma drug conc. | 3.7/3.4 | 4.0/3.9 | - (-/-) | 3 |
| SPYRAL HTN-OFF MED, 2017 | Multiple | Sham only | 80 (38/42) | Plasma drug conc. | 92.1/88.1 (off med %) | 94.3/92.7 (off med %) | - (-/-) | 5 |
| SPYRAL HTN-ON MED, 2018 | Multiple | Sham + usual drugs | 80 (38/42) | Plasma drug conc. | 2.2/2.3 | -/- | 0/0 | 5 |
SSAHT, standardized stepped-care antihypertensive treatment.