CRUCIAL 2011.
| Methods | Open label cluster randomised trial | |
| Participants | 136 clusters; 1461 total participants (779 intervention; 682 control participants), men and women aged 35-79 years with hypertension and total cholesterol <250 mg/dl plus three or more risk factors (current smoker, peripheral artery disease, type 2 diabetes, family history of early CHD before aged 55 years in first dgree relative; left ventricular hypertrophy on electrocardiogram [ECG]; history of transient ischemic attack or stroke three or more months prior to screening; ECG abnormalities; age >55 years [men] or >65 years [women], total cholesterol >250mg/dl, or HDL <40mg/dl) | |
| Interventions | Intervention: Single pill amlodipine/atorvastatin (5mg/10mg to 10mg/10mg; site investigators could request dosages of 5/20 mg and 10/20 mg) in addition to other hypertensive / lipid lowering therapy as required, as well as therapeutic lifestyle counselling change Control: Usual care, including therapeutic lifestyle counselling change |
|
| Outcomes | SBP, DBP, LDL-C, total cholesterol; all-cause mortality reported | |
| Notes | Control: inactive/usual care | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | “Investigators - randomly assigned”, “randomisation was stratified”, “investigator as unit of randomisation” |
| Allocation concealment (selection bias) | Unclear risk | Due to cluster randomisation |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | Open label |
| Blinding of outcome assessment (detection bias) All outcomes | High risk | Open label |
| Incomplete outcome data (attrition bias) All outcomes | High risk | 93/779 (11.9%) discontinued intervention; 44/682 (6.5%) discontinued in usual care arm |
| Selective reporting (reporting bias) | Unclear risk | Not all outcomes available for meta-analysis |
| Other bias | Unclear risk | Significant differences between two arms in terms of baseline blood pressure and ECG abnormalities/PVD; underpowered according to authors' own calculations; different doses of intervention were available upon request to investigators |