Predicting complications from acute cough in pre-school children in primary care: a prospective cohort study.

BACKGROUND There is uncertainty about which children with cough are most and least likely to experience complications. AIM To derive a clinical prediction rule for complications in pre-school children presenting to primary care with acute cough. DESIGN OF STUDY Prospective cohort study. SETTING Eight general practices in Leicestershire, United Kingdom. METHOD Pre-school children with cough for < or =28 days and without asthma were recruited. Sociodemographic, clinical history, and examination data were collected and univariable logistic regression used to explore the associations with complications. These were defined as any new symptom, sign or diagnosis identified by a primary care clinician at a parent initiated reconsultation, or hospital admission, before cough resolution. Those factors with stronger relationships (P< 0.2) were then modelled using multivariable logistic regression to identify the factors independently associated with complications. RESULTS The pre-test probability of complications was 10%. On univariable analysis, fever (odds ratio [OR] = 4.86; 95% confidence interval [CI] = 1.74 to 13.6), chest signs (OR = 2.72; CI = 1.06 to 6.96), and tachypnoea (OR = 3.80; CI = 1.22 to 11.8) were associated with complications. On multivariable analysis, only fever (OR = 5.56; CI = 1.75 to 17.6) and chest signs (OR = 2.88; CI = 1.02 to 8.05) were independently associated with complications. These ORs translate into post-test probabilities of complications of 6% for children with neither fever nor chest signs, 18% for children with chest signs, 28% for children with fever, and 40% for children with fever and chest signs. CONCLUSIONS If validated, this clinical prediction rule could be used to individualise the management of acute cough in pre-school children.