title: A rapid desktop theophylline assay. Evaluation of use in clinical management.
abstract: OBJECTIVE
  To assess the practicality and precision of a simple desktop theophylline assay (Biotrack 516TM) in comparison to a standard laboratory assay system (Abbott TDxTM).
  
  
  METHODS
  A prospective blinded paired sample study.
  
  
  METHODS
  The respiratory ward and outpatient clinics, the pulmonary function and biochemistry laboratories of a university teaching hospital.
  
  
  METHODS
  Sixty patients with asthma or COPD attending the respiratory service.
  
  
  RESULTS
  Paired specimens for theophylline assay were collected simultaneously for analysis. There was a highly significant (p < 0.001) correlation between the two assay systems for both the total range studied (1.2-39.1 micrograms/mL; r = 0.98), and the clinically important range of 5-15 micrograms/mL (r = 0.95). The limits of agreement for the data by the Bland and Altman method indicated a +/-2 micrograms/mL limit for the 5-15 micrograms/mL range and a +/-2.7 micrograms/mL limit for the total range studied.
  
  
  CONCLUSIONS
  The Biotrack 516 is an easy-to-use system, which provides rapid and reasonably precise measurements of serum theophylline levels. The device should be of particular value in smaller centers without an on-site laboratory assay system.
authors.affiliation: Department of Respiratory Medicine, St. Vincent's Hospital, Dublin, Ireland.
authors.forename: J L
authors.initials: JL
authors.lastname: Kiely
authors.forename: G
authors.initials: G
authors.lastname: Lawless
authors.forename: S
authors.initials: S
authors.lastname: Cunningham
authors.forename: W T
authors.initials: WT
authors.lastname: McNicholas
mesh_terms: D005069:Evaluation Studies as Topic; D006801:Humans; D007118:Immunoassay / Q000191:economics / Q000379:methods*; D011446:Prospective Studies; D016037:Single-Blind Method; D013806:Theophylline / Q000097:blood*
chemical_list: D013806:Theophylline