title: Psychometric Evaluation of the Ford Insomnia Response to Stress Test (FIRST) in Early Pregnancy.
abstract: OBJECTIVE
  To evaluate the construct validity and factor structure of the Spanish-language version of the Ford Insomnia Response to Stress Test questionnaire (FIRST-S) when used in early pregnancy.
  
  
  METHODS
  A cohort of 647 women were interviewed at ≤ 16 weeks of gestation to collect information regarding lifestyle, demographic, and sleep characteristics. The factorial structure of the FIRST-S was tested through exploratory and confirmatory factor analyses (EFA and CFA). Internal consistency and construct validity were also assessed by evaluating the association between the FIRST-S with symptoms of depression, anxiety, and sleep quality. Item response theory (IRT) analyses were conducted to complement classical test theory (CTT) analytic approaches.
  
  
  RESULTS
  The mean score of the FIRST-S was 13.8 (range: 9-33). The results of the EFA showed that the FIRST-S contained a one-factor solution that accounted for 69.8% of the variance. The FIRST-S items showed good internal consistency (Cronbach α = 0.81). CFA results corroborated the one-factor structure finding from the EFA; and yielded measures indicating goodness of fit (comparative fit index of 0.902) and accuracy (root mean square error of approximation of 0.057). The FIRST-S had good construct validity as demonstrated by statistically significant associations of FIRST-S scores with sleep quality, antepartum depression and anxiety symptoms. Finally, results from IRT analyses suggested excellent item infit and outfit measures.
  
  
  CONCLUSIONS
  The FIRST-S was found to have good construct validity and internal consistency for assessing vulnerability to insomnia during early pregnancy.
authors: Department of Epidemiology, Harvard School of Public Health, Boston, MA.
authors: Bizu
authors: B
authors: Gelaye
authors: Department of Epidemiology, Harvard School of Public Health, Boston, MA.
authors: Qiu-Yue
authors: QY
authors: Zhong
authors: Department of Epidemiology, Harvard School of Public Health, Boston, MA.
authors: Yasmin V
authors: YV
authors: Barrios
authors: Department of Epidemiology, Harvard School of Public Health, Boston, MA.|Department of Medicine, Brigham and Women's Hospital, Boston, MA.|Harvard Medical School, Boston, MA.
authors: Susan
authors: S
authors: Redline
authors: Sleep Disorders and Research Center, Henry Ford Hospital, Detroit, MI.
authors: Christopher L
authors: CL
authors: Drake
authors: Department of Epidemiology, Harvard School of Public Health, Boston, MA.
authors: Michelle A
authors: MA
authors: Williams
mesh_terms: D000293:Adolescent; D000328:Adult; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D010568:Peru; D011247:Pregnancy; D011248:Pregnancy Complications / Q000523:psychology*; D011261:Pregnancy Trimester, First; D011594:Psychometrics; D015203:Reproducibility of Results; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications* / Q000523:psychology*; D013315:Stress, Psychological / Q000150:complications* / Q000523:psychology*; D011795:Surveys and Questionnaires; D014175:Translating; D055815:Young Adult
keywords: FIRST; Peru; pregnancy; stress-related sleep disturbance