Tummy time, health and development in infants

Background: Tummy time is recommended by the World Health Organization (WHO) to improve infant motor development. These recommendations are based on proxy-questionnaires that rely on parent recall. As a result, the association and effectiveness of tummy time on infant health outcomes using objective realtime measurement techniques are unknown. A sequence of studies based on the behavioural epidemiology framework will contribute to strengthen the evidence regarding tummy time recommendations. Aims: To investigate 1) the prevalence of tummy time; 2) the association of tummy time with infant health outcomes; 3) the validation of accelerometers to objectively measure tummy time; 4) the correlates of tummy time; and 5) an intervention to promote tummy time. Methods: A thesis by compilation of six manuscripts. The six manuscripts include 1) an observational study to determine the prevalence of tummy time (Study 1); 2) two systematic reviews, with one investigating the association of tummy time with infant health outcomes (Study 2), and the second investigating the correlates of tummy time (Study 5); 3) two measurement validation studies, with one validating objective measures of tummy time (Study 3) and the second determining how to define wear and non-wear time of the GENEActiv accelerometer when worn by infants (Study 4); and 4) a pilot randomised controlled trial to assess the feasibility, acceptability and potential efficacy of a tummy time intervention (Study 6).