Table 1

Characteristics of diagnostic subgroups

  • PNDS = post-nasal drip syndrome; GOR = gastro-oesophageal reflux; CVA = cough variant asthma.

  • Atopic status based on history and total serum IgE (normal <120 kU/l) and specific serum IgE to four common inhaled allergens (house dust mite, mixed grasses, epithelia mix and cat/dog dander) (score <1 rated negative) measured by radioallergosorbent test (RAST).