Validation of the Pregnancy Asthma Control Test.

BACKGROUND: Suboptimal asthma control during pregnancy may affect perinatal outcomes. US guidelines recommend questionnaires to assess asthma control including the Asthma Control Test (ACT).
OBJECTIVE: To validate telephone administration of a modified version of ACT during pregnancy.
METHODS: MotherToBaby Pregnancy Studies (2011-2013) enrolled 159 pregnant women with asthma. Participants were interviewed by telephone at intake, at approximately gestational weeks 20 and 32, and postpartum. The ACT was modified to address dyspnea specifically due to asthma; the modified version is the Pregnancy Asthma Control Test (p-ACT). Women answered the p-ACT and guideline-based asthma impairment questions and reported asthma course changes and exacerbations. Possible p-ACT scores ranged from 5 to 25; higher score indicated better control. Reliability, criterion validity, construct validity, prospective validity, and responsiveness were assessed.
RESULTS: Cronbach's alpha for internal consistency was similar across time points (0.84-0.90). The p-ACT score varied by impairment; for example, at intake, the mean score was 23.2 for well-controlled versus 13.7 for very poorly controlled asthma. The p-ACT score change between interviews differed by asthma course; for example, women reporting that their asthma was much better at week 20 than at intake had a mean score increase of 4.7; women reporting that their asthma was a little worse had a mean score decrease of 1.3. Lower p-ACT score was associated with previous exacerbations, whereas intake p-ACT score was not associated with future exacerbations during pregnancy.
CONCLUSIONS: The p-ACT demonstrated good internal consistency, varied in the expected direction by impairment level, and was responsive to changes in asthma course. Telephone administration of the p-ACT is reliable and valid for assessing asthma control during pregnancy.