Validity and Reliability of the Spanish Version of the Pregnancy-Related Thoughts Scale

To adapt the Pregnancy-Related Thoughts Scale into Spanish (Spanish PRTS) and evaluate its psychometric properties.

Instrument translation (Phase 1), validation, and psychometric testing (Phase 2).

Phase 2 was conducted in three general hospitals in eastern Spain.

A convenience sample of 180 women during the third trimester of pregnancy participated in Phase 2.

After a standard process of linguistic validation in Phase 1, we used the Spanish PRTS with other instruments to evaluate its psychometric properties in Phase 2. The participants completed a battery of questionnaires during prenatal visits in the third trimester (28-42 weeks gestation) at health care centers. Responses to the postnatal depression questionnaire were obtained through an online questionnaire between the first and third months after childbirth. We evaluated the factor structure; reliability; and convergent, discriminant, and predictive validity of the Spanish PRTS.

The Spanish PRTS had a Cronbach's alpha coefficient of .81 and McDonald's omega coefficient of .82. The confirmatory factor analysis showed that the best adjustment of the scale was one factor with two pairs of correlated residuals. The Spanish PRTS scores were positively correlated to scores on pregnancy worries, state and trait anxiety, fatigue, symptoms of postnatal depression, and poor quality of life and inversely correlated to scores on self-efficacy for coping with stress.

The findings support the validity and reliability of the Spanish PRTS to evaluate pregnancy-related anxiety; this tool can be used to measure outcomes of interventions for the prevention or treatment of women's anxiety during pregnancy.