Consistency of maternal telephone administration of the asthma control test using postpartum recall compared to repeated measures during pregnancy.

Background: Suboptimal asthma control during pregnancy may impact perinatal outcomes. U.S. guidelines recommend questionnaires to assess asthma control including the Asthma Control Test (ACT). It is unknown in a research setting to what extent recall differs by the time between symptom occurrence and the administration of the questionnaire.

Methods: Between 2009-2014, 196 pregnant asthmatic women were recruited by the Organization of Teratology Information Specialists (OTIS) MotherToBaby Pregnancy Studies. Participants were administered the ACT at enrollment, gestational weeks 20 and 32, and shortly after delivery. The same women were also administered the ACT retrospectively at approximately 6 months postpartum.

Results: The Pearson correlation coefficients between the in-pregnancy and retrospective continuous ACT scores for the 1st, 2nd and 3rd trimesters were: 0.67 (95% CI: 0.58, 0.74), 0.61 (0.52, 0.70) and 0.65 (0.56, 0.72), respectively. When dichotomized into well-controlled asthma (ACT score ≥ 20) versus otherwise, the chi-square test for all three trimesters resulted in p values <0.0001. Cohen's Kappa statistics for the same dichotomized scores were 0.51, 0.45 and 0.40 for each trimester respectively. There was no evidence that adverse outcome of pregnancy (recall bias) influenced postpartum responses.

Conclusions: The retrospectively recalled ACT score obtained postpartum was substantially different compared to in-pregnancy administration of the same questionnaire which could reflect test-retest variability as well as attenuation of recall. Documentation of the magnitude and direction of these differences could be useful in interpretation of the impact of asthma control when the ACT is used in retrospective case-control studies for pregnancy outcomes.