Economic considerations increasingly play a role in the selection of antidepressant drugs and are often based on analyses from prospective and retrospective studies. However, the non-randomisation found in retrospective studies may result in significant selection bias.

To highlight the use of statistical methods in non-randomised studies and the application of those methods to economic analyses.

The literature on the observational studies of economic outcomes with alternative antidepressants is reviewed and several statistical methodologies to control for biases that can occur in non-randomised study designs are described.

In comparisons of antidepressant drugs, differences in acquisition costs are consistently found to be at least offset by other components of care when broad measures of health care resource utilisation are considered.

Economic evaluations of antidepressants should be based on broad measures of health care expenditure and can rely on data generated in real-world settings if appropriate statistical methods are used to control for the potential biases of non-randomisation.

The sequelae of profound early privation are varied.

To delineate the behavioural patterns that are specifically associated with institutional privation.

A group of 165 children adopted from Romania before the age of 42 months were compared at 4 years and 6 years with 52 non-deprived UK children adopted in infancy. Dysfunction was assessed for seven domains of functioning. The groups were compared on which, and how many, domains were impaired.

Attachment problems, inattention/overactivity, quasi-autistic features and cognitive impairment were associated with institutional privation, but emotional difficulties, poor peer relationships and conduct problems were not. Nevertheless, one-fifth of children who spent the longest time in institutions showed normal functioning.

Attachment disorder behaviours, inattention/overactivity and quasi-autistic behaviour constitute institutional privation patterns.