Table 2

Primary outcomes of feasibility and adherence

Adherence and feasibility parameterLow-dose aspirin
(n=179)
No aspirin
(n=183)
Screen and treat
(n=184)
Ease of Doppler acquisition
 Very easy8 (4%)
 Easy53 (29%)
 Fair61 (33%)
 Difficult60 (32%)
 Unobtainable3 (2%)
 Days to PLGF/PAPP-A visit 17.6 (0–26)
 PLGF/PAPP-A result>16 weeks5 (3%)
Time taken for visit 1 (minutes)60 (30–100)60 (25–90)60 (25–90)
Median adherence tablet counts96%95% (screen positive)
Median adherence diary cards94%95% (screen positive)
Non-adherent7 (4%)0 (0%)
  • PAPP-A, pregnancy-associated plasma protein-A; PLGF, placental-like growth factor.