STUDY OF INTEROBSERVER RELIABILITY IN CLINICAL-ASSESSMENT OF RSV LOWER RESPIRATORY ILLNESS - A PEDIATRIC INVESTIGATORS COLLABORATIVE NETWORK FOR INFECTIONS IN CANADA (PICNIC) STUDY

Randomized trials of ribavirin therapy have used clinical scores to as sess illness severity. Little information on agreement for these findi ngs between observers has been published. We decided to determine inte robserver agreement for (1) a history for apnea or respiratory failure ; (2) assessment of cyanosis, respiratory rate, retractions, and oxime try; and (3) determination of reason for hospitalization (requirement for medications, supportive care, underlying illness, poor home enviro nment). At eight centers 137 RSV-infected patients were assessed by tw o observers blinded to the assessments by others with no interventions made between assessments. Observations were categorized, and agreemen t was summarized as percentage of observed agreement, Pearson correlat ion, or as a kappa statistic. Observed agreement for a history of eith er apnea or a respiratory arrest was at least 90% at all centers, with seven of the eight centers in total agreement. At all centers except one, the agreement on the reason why the patient remained in hospital was at least 80%. The observed agreement for assessing cyanosis was at least 94% at all eight centers. The correlation coefficient for respi ratory rate varied from 0.42 to 0.97 across centers. The kappa values for agreement beyond chance for retractions varied from 0.05 to 1.00. The kappa values for oxygen saturation measures varied from 0.31 to 0. 70. Although not statistically significant, there appeared to be more variation as the time between assessments increased. In conclusion, ag reement for historical findings and assessment of cyanosis was high. H owever, there was wide variation in agreement in the other assessments . Training to ensure consistent and reproducible assessment by differe nt examiners will be necessary if these findings are to be used as out come variables in clinical trials. (C) 1996 Wiley-Liss, Inc.