A COLLABORATIVE STUDY OF INFANT RESPIRATORY-FUNCTION TESTING

The aims of this study were to compare inter-observer variability with in and between two specialized infant lung function testing centres an d to develop a strategy for performing and analysing infant respirator y function tests to facilitate future collaborative trials. A protocol for data collection and analysis,vas developed using similar equipmen t and identical software, All raw data were exchanged on disk and anal ysed, blind to infant status. All data were cross-analysed by both cen tres to assess inter-observer variability. Outcome measures were funct ional residual capacity (FRCpleth), airway resistance (Raw) and maxima l expiratory flow at FRC (V'max,FRC). Subjects were recruited from the multicentre UK extracorporeal membrane oxygenation (ECMO) Trial and m easured at around 1 yr of age. Forty-two infants attended the Institut e of Child Health, London and 36 attended the Leicester Royal Infirmar y. The proportion of infants treated with ECMO or conventional managem ent at each centre was similar, There were no significant differences between any of the outcome measures for infants tested at either centr e, During a cross-analysis, the agreement between the two centres, wit hin infant, was closer for V'max,FRC and FRCpleth (within 10%) than fo r the more variable measurements of Raw (within 20%), A collaborative approach to trials with infant respiratory function as an outcome meas ure appears feasible, providing that close attention is paid to study design, and participants in such trials maintain a standard approach t o data collection and analysis. (C) ERS Journals Ltd 1998.