OBJECTIVES: To critically appraise published cost-utility analyses of interventions in child and adolescent health care in terms of the methods used to estimate quality-adjusted life years (QALYs). METHODS: A comprehensive search of computerised databases (e.g. Medline, Embase) was undertaken to identify cost-utility studies published prior to April 2004. Studies were categorised according to the methods used to describe health status, the valuation technique and source of preferences. The methods were compared with the guidelines of the U.S. Panel on Cost-effectiveness in Health and Medicine and the National Institute for Clinical Excellence (NICE) in England and Wales which recommend the use of a generic health status classification system (e.g. HUI, EQ-5D), a choice-based valuation method (e.g. SG or TTO), and preferences of the general population. RESULTS: Fifty-four studies were reviewed, of which 34 (63%) were published in the latter five years. A generic health status classification instrument was used in 22 (35%) cases; the remainder developed study specific health state descriptions or elicited preferences directly from patients or proxies. In 7 cases (11%), sources were unclear. Utility values were elicited by using choice-based techniques in 28 cases (42%), either as tariffs for health status classification instruments (17 cases) or by directly valuing health state descriptions or patient health (11 cases). Community preferences were only used in 23 cases (37%). Four studies aggregated QALYs for mother/child or family/child pairs without giving any theoretical justification. CONCLUSIONS: Although the number of cost utility studies is increasing exponentially, the majority of studies did not adhere to standard recommendations with little improvement over time. Further research is warranted to develop appropriate methods to measure and value child health benefits within the QALY framework. In the interim, an expert panel is needed to provide guidance for cost-utility analysis of paediatric interventions to make studies more consistent.