Although unattended ambulatory polysomnography (PSG) is frequently performed in adults, few studies have been performed in children. The objective of this study was to evaluate the feasibility of comprehensive, ambulatory PSG, including electroencephalography, in school-aged children in the home environment. METHODS: A total of 201 children, born premature with birth weights of 500-1,250 grams, currently aged 5-12 years and living in Canada and Australia, underwent unattended ambulatory PSG. RESULTS: PSG was initially technically satisfactory in 183 (91 ) cases. Fourteen studies were satisfactory when repeated, resulting in an overall satisfactory rate of 197 (98 ). Artifact-free signals were obtained for >/= 75 of recording time in more than 92 of subjects, with the exception of nasal pressure, which was satisfactory for >/= 75 of recording time in only 67 of subjects. However, thermistry signals were satisfactory for >/= 75 of recording time in 92 of subjects, and some measure of airflow was present for >/= 75 of recording time in 96 of subjects. Children slept very well, with a long total sleep time (534 +/- 73 [mean +/- SD] minutes), high sleep efficiency (92 +/- 5 ), and low arousal index (9 +/- 3/h). Parents and children reported a high rate of satisfaction with the study. This large, international study has shown that comprehensive, unattended, ambulatory PSG is feasible, technically adequate and well-tolerated in school-aged children when performed under research conditions. Further studies regarding the cost efficacy of this approach, and generalizability of the findings to a clinical population, are warranted.