A policy statement on controlled crying issued by the Australian Association of Infant Mental Health (AAIMHI) advises, “Controlled crying is not consistent with what infants need for their optimal emotional and psychological health, and may have unintended negative consequences.” According to AAIMHI, “There have been no studies, such as sleep laboratory studies, to our knowledge, that assess the physiological stress levels of infants who undergo controlled crying, or its emotional or psychological impact on the developing child.”