Table 1.

Number of patients considered to have a diagnosis of asthma as produced by the hierarchical computer search strategy.

Search strategy	Number of patients
Read coded asthma	670
Asthma screen attendance	39
Asthma screen intervention record	0
Textual disease label entry containing ‘asthma’ ‘wheez’	73
Inhaled steroids available on a repeat basis	27
Inhaled bronchodilators on a repeat basis	24
Mast cell stabilisers (cromolyns) on a repeat basis	0