MEASUREMENT PROPERTIES OF THE CLINICAL-RISK-INDEX FOR BABIES - RELIABILITY, VALIDITY BEYOND THE FIRST 12 HOURS, AND RESPONSIVENESS OVER 7 DAYS

Objectives: Clinical Risk index far Babies (CRIB) is a simple instrume nt used to measure clinical risk and illness severity in very low birt h-weight infants. We assessed its reliability, validity beyond the fir st 12 hrs after birth, and responsiveness to individual change in cond ition after 7 days. Design: Cohort study. Setting: Three tertiary and three nontertiary UK hospitals. Patients: Three hundred ninety-eight i nfants whose birth weight was <1501 g or who were born before a 31-wk gestation period. Interventions: Inter- and intrarater reliability of data extraction were assessed by Pearson and intraclass correlation. T o validate CRIB, we tested the correlation between clinical risk and i llness severity with the risk of: a) death; b) prolonged treatment wit h supplemental oxygen; and c) disability at 2 yrs. Logistic regression models were fitted to assess validity and responsiveness.Measurements and Main Results: Reliability coefficients ranged from 0.76 (95% conf idence interval, 0.71 to 0.81) to 0.97 (0.94 to 1.00). Throughout the first week, CRIB correlated with the risk of death (p < .001), prolong ed treatment with oxygen (p < .001), and disability (p < .001 to p = . 033). Improved condition, represented by a reduction in CRIB within th e first week, was independently associated with lower risks of each ad verse outcome, p < .05. Conclusions: During the first week, CRIB was r eliable, valid, and responsive. These properties support the use of CR IB in the stratification of infants by risk and illness severity in co hort studies, and they also indicate that CRIB may have the potential to be used in other ways in the future.