OBJECTIVES: Quality-adjusted life-years (QALYs) measure the number of years of perfect health provided by a health care intervention, and are a useful measure because they combine mortality and morbidity in one scale. QALYS are considered the “gold-standard” for assessing the effectiveness, and thus cost-effectiveness, of new interventions and are requested by most reimbursement agencies, such as the UK NICE. Utility data (generally gained through quality-of-life instruments) are required to calculate QALYs, however such data may not be available for some drug indications. As a result, these drug indications are not suitable for assessment via QALYs. We sought to clarify the extent to which this is a problem. METHODS: We reviewed all prescription drugs (including new preparations of existing drugs) approved by the UK regulatory agency, the MHRA. Using an online database of utility scores from Tufts University, we conducted various descriptive analyses. Our primary analysis was to establish the percentage of licensed drugs for which utility scores are available and thus for which QALYs are a possible effectiveness measure. RESULTS: Interim analysis of 93 licensed preparations showed that 73% had utility data available. This leaves a substantial proportion of drugs for which QALYs may be difficult or impossible to obtain. Where QALYs are difficult to obtain, this may limit the confidence with which they can be interpreted. In other cases, QALYs may be irrelevant: these include important indications such as anaesthesia and contraception. CONCLUSIONS: It is important for reimbursement agencies to recognise that QALYs are not a universal measure, and that flexibility is required for indications in which QALYs cannot be used. An over-emphasis on QALYs may lead to a bias against positive recommendations in disease areas where QALYS cannot be used.