Brief infant sleep questionnaire. A

Brief infant sleep questionnaire. All mothers completed an expanded ver-sion of the Brief Infant Sleep Questionnaire (BISQ) (Sadeh, 2004). The BISQ has
been validated against actigraphy and daily-logs and its sensitivity in documenting
expected developmental trends in young children’s sleep and the effects of envi-ronmental factors have been established. Test-retest reliability for individual sleep
measures on the BISQ was high (r=.81 to .95), as were comparisons between the
BISQ and actigraphy (r=.23 to .54) (Sadeh, 2004). The expanded version of the
BISQ, as described previously (Sadeh et al., 2009), included questions about the
child’s daytime and nighttime sleep patterns, sleep-related behaviors, and mater-nal perceptions. The BISQ was completed at baseline and at four follow-up visits
(3, 6, 9, and 12–18 months later). At each time point, seven items from the BISQ
were assessed (sleep onset latency, number of night wakings, longest continuous
sleep period, total sleep time at night, how often wakes in own bed, number of daytime naps, and parent considers sleep a problem). These variables were chosen based on previous research (Mindell, Telofski, Wiegand, & Kurtz, 2009; Sadeh et al., 2009). Parental presence at sleep onset was derived from parents’ response to the item“Howdoes your child fall asleepmost of the time?”, with parental pres-ence indicated for all applicable responses (e.g., while being fed, rocked, held, in parent’s bed with a parent in the room”) or coded as not present (e.g., in parent’s bed alone in the room, in his/her own crib and without a parent in the room), as assessed in previous studies (Sadeh, Mindell, & Rivera, 2011; Sadeh et al.,
2009)