Development and an initial validation of the Responses to Illness Severity Quantification (RISQ) score for severely malnourished children

Aim To develop and perform an initial validation of a score to measure the severity of illness in hospitalised children with severe acute malnutrition (SAM). Methods A prospective study enrolled SAM children aged 6-59 months hospitalised in Borno State, Nigeria. Candidate items associated with inpatient mortality were combined and evaluated as candidate scores. Clinical and statistical methods were used to identify a preferred score. Results The 513 children enrolled had a mean age of 15.6 months of whom 48 (9%) died. Seven of the 10 evaluated items were significantly associated with mortality. Five different candidate scores were tested. The final score, Responses to Illness Severity Quantification (RISQ), included seven items: heart rate, respiratory rate, respiratory effort, oxygen saturation, oxygen delivery, temperature and level of consciousness. The mean RISQ score on admission was 2.6 in hospital survivors and 7.3 for children dying <48 h. RISQ scores <24 h before death had an area under the receiver operating characteristic curve (AUROC) of 0.93. The RISQ score performed similarly across differing clinical conditions with AUROCs 0.77-0.98 for all conditions except oedema. Conclusion The RISQ score can identify high-risk malnourished children at and during hospital admission. Clinical application may help prioritise care and potentially improve survival.