A comprehensive evaluation of symptom scores designed to inform the
triage and diagnosis of cow’s milk protein allergy in children: a
systematic review of the research evidence
Background: Cow’s milk protein allergy (CMPA) is an immune-mediated
allergic response to proteins in milk, a common infant food allergy. The
wide range and frequency of CMPA symptoms make diagnosis a challenge,
particularly in primary care. Symptom scores may improve a clinician’s
awareness of symptoms, thus indicating a need for further testing. This
systematic review examined the development and evaluation of such
symptom scores for use in infants. Methods: Four databases were searched
from inception to 3 December 2019, for diagnostic accuracy studies,
randomised controlled trials, observational studies, economic
evaluations, qualitative studies, and studies reporting on the
development of the tools. Experts were consulted for additional studies.
Data were not suitable for meta-analysis due to heterogeneity, so were
narratively synthesised. Results: We found two symptom scores evaluated
in one and fourteen studies, respectively. Estimated sensitivity and
specificity ranged from 37-98% and 38-93%. The evaluations of each
tool were at high risk of bias or failed to address issues such as
clinical and cost-effectiveness. Conclusions: Estimates of accuracy of
symptom scores for CMPA offered so far should be interpreted cautiously.
Rigorous research based on well-defined roles for the tools and free of
potential conflicts of interest is urgently required.