DESIGN: Retrospective observational analysis.

SETTING: 56 acute stroke hospitals in eight countries.

PARTICIPANTS: 1074 trial physiotherapists, nurses, and other clinicians.

OUTCOME MEASURES: Number of babies born during trial recruitment per trial participant recruited.

RESULTS: With 198 site recruitment years and 2104 patients recruited during AVERT, 120 babies were born to trial staff. Births led to an estimated 10% loss in time to achieve recruitment. Parental leave was linked to six trial site closures. The number of participants needed to recruit per baby born was 17.5 (95% confidence interval 14.7 to 21.0); additional trial costs associated with each birth were estimated at 5736 Australian dollars on average.

CONCLUSION: The staff absences registered in AVERT owing to parental leave led to delayed trial recruitment and increased costs, and should be considered by trial investigators when planning research and estimating budgets. However, the celebration of new life became a highlight of the annual AVERT collaborators' meetings and helped maintain a cohesive collaborative group.

TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry no 12606000185561.

METHODS: Blinded assessors coded baseline images for acute ischaemic signs (presence, extent, swelling and attenuation of acute lesions; and hyperattenuated arteries) and pre-existing changes (atrophy, leucoaraiosis and old ischaemic lesions). Logistic regression models assessed associations between imaging features and death at 7 and 90 days; good recovery (modified Rankin Scale scores 0-2 at 90 days) and sICH. Data are reported with adjusted ORs and 95% CIs.

RESULTS: 2916 patients (67±13 years, National Institutes of Health Stroke Scale 8 (5-14)) were included. Visible ischaemic lesions, severe hypoattenuation, large ischaemic lesion, swelling and hyperattenuated arteries were associated with 7-day death (OR (95% CI): 1.52 (1.06 to 2.18); 1.51 (1.01 to 2.18); 2.67 (1.52 to 4.71); 1.49 (1.03 to 2.14) and 2.17 (1.48 to 3.18)) and inversely with good outcome. Severe atrophy was inversely associated with 7-day death (0.52 (0.29 to 0.96)). Atrophy (1.52 (1.08 to 2.15)) and severe leucoaraiosis (1.74 (1.20 to 2.54)) were associated with 90-day death. Hyperattenuated arteries were associated with sICH (1.71 (1.01 to 2.89)). No imaging features modified the effect of alteplase dose.

DESIGN: AVERT is a prospective, parallel group, assessor-blinded randomised clinical trial. This paper presents data assessing the generalisability of AVERT.

SETTING: Acute stroke units at 44 hospitals in 8 countries.

PARTICIPANTS: The first 20,000 patients screened for AVERT, of whom 1158 were recruited and randomised.

MODEL: We use the Proximal Similarity Model, which considers the person, place, and setting and practice, as a framework for considering generalisability. As well as comparing the recruited patients with the target population, we also performed an exploratory analysis of the demographic, clinical, site and process factors associated with recruitment.

RESULTS: The demographics and stroke characteristics of the included patients in the trial were broadly similar to population-based norms, with the exception that AVERT had a greater proportion of men. The most common reason for non-recruitment was late arrival to hospital (ie, >24 h). Overall, being older and female reduced the odds of recruitment to the trial. More women than men were excluded for most of the reasons, including refusal. The odds of exclusion due to early deterioration were particularly high for those with severe stroke (OR=10.4, p<0.001, 95% CI 9.27 to 11.65).

CONCLUSIONS: A model which explores person, place, and setting and practice factors can provide important information about the external validity of a trial, and could be applied to other clinical trials.

OBJECTIVES: The Triple Therapy Prevention of Recurrent Intracerebral Disease Events Trial (TRIDENT) aims to determine the effects of a novel SPC "Triple Pill," three generic antihypertensive drugs with demonstrated efficacy and complementary mechanisms of action at half standard dose (telmisartan 20 mg, amlodipine 2.5 mg, and indapamide 1.25 mg), with placebo for the prevention of recurrent stroke, cardiovascular events, and cognitive impairment after ICH.

DESIGN: An international, double-blind, placebo-controlled, randomized trial in adults with ICH and mild-moderate hypertension (systolic BP: 130-160 mmHg), who are not taking any Triple Pill component drug at greater than half-dose. A total of 1500 randomized patients provide 90% power to detect a hazard ratio of 0.5, over an average follow-up of 3 years, according to a total primary event rate (any stroke) of 12% in the control arm and other assumptions. Secondary outcomes include recurrent ICH, cardiovascular events, and safety.

RESULTS: Recruitment started 28 September 2017. Up to 31 October 2021, 821 patients were randomized at 54 active sites in 10 countries. Triple Pill adherence after 30 months is 86%. The required sample size should be achieved by 2024.